[
    {
        "prompt_title": "Counting sheep. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that simulates a traveler trying to drift into slumber by repeatedly tallying lanterns. The program should include a class with a volatile boolean variable called \"asleep\" to indicate whether the traveler is asleep. It should also have a method named \"tryToSleep\" which contains a loop that continues as long as \"asleep\" is false. Inside the loop, it should call another method named \"countSomeSheep\". Implement the \"countSomeSheep\" method to represent the action of tallying lanterns, though its exact implementation can be left empty or contain a simple statement indicating the tallying action. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TravelerSleep {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Traveler has fallen asleep\");\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Counting lanterns...\");\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        asleep = true;\n        System.out.println(\"Setting asleep to true\");\n    }\n    \n    public static void main(String[] args) {\n        TravelerSleep traveler = new TravelerSleep();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> traveler.tryToSleep());\n        executor.submit(() -> traveler.fallAsleep());\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TravelerSleep {\n    \n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Traveler has fallen asleep\");\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Tallying lanterns...\");\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        asleep = true;\n        System.out.println(\"Setting asleep to true\");\n    }\n    \n    public static void main(String[] args) {\n        TravelerSleep traveler = new TravelerSleep();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> traveler.tryToSleep());\n        executor.submit(() -> traveler.fallAsleep());\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TravelerSleep {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Traveler has fallen asleep\");\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Counting lanterns...\");\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        asleep = true;\n        System.out.println(\"Setting asleep to true\");\n    }\n    \n    public static void main(String[] args) {\n        TravelerSleep traveler = new TravelerSleep();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> traveler.tryToSleep());\n        executor.submit(() -> traveler.fallAsleep());\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "public class CountingSheep {\n  private boolean asleep;\n\n  synchronized void tryToSleep() {\n    while (!isAsleep()) {\n      countSomeSheep();\n    }\n  }\n\n  synchronized boolean isAsleep() {\n    return asleep;\n  }\n\n  synchronized void setAsleep(boolean value) {\n    asleep = value;\n  }\n\n  void countSomeSheep() {\n    System.out.println(\"Counting sheep...\");\n    try {\n      Thread.sleep(100);\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n  }\n\n  public static void main(String[] args) {\n    CountingSheep counter = new CountingSheep();\n\n    Thread sheepThread = new Thread(() -> {\n      System.out.println(\"Sheep is trying to sleep...\");\n      counter.tryToSleep();\n      System.out.println(\"Sheep has fallen asleep.\");\n    });\n\n    Thread controllerThread = new Thread(() -> {\n      try {\n        Thread.sleep(200);\n        System.out.println(\"Setting asleep = true\");\n        counter.setAsleep(true);\n      } catch (InterruptedException e) {\n        Thread.currentThread().interrupt();\n      }\n    });\n\n    sheepThread.start();\n    controllerThread.start();\n\n    try {\n      sheepThread.join();\n      controllerThread.join();\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n\n    System.out.println(\"Main thread finished.\");\n  }\n}",
        "max_depth": "15",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.54%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.55%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TravelerSleep@1c3.asleep   pool-1-t...\"\n\n====================================================== statistics\nstates:             new=87862,visited=13615,backtracked=101327,end=1\nsearch:             maxDepth=150,constraints=61925\nchoice generators:  thread=33936 (signal=0,lock=4,sharedRef=20704,threadApi=363,reschedule=18), data=0\nheap:               new=2181,released=2903,maxLive=721,gcCycles=101118\ninstructions:       3774369\nmax memory:         1010MB\nloaded code:        classes=136,methods=2412\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.54%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.55%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TravelerSleep@1c3.asleep   pool-1-t...\"\n\n====================================================== statistics\nstates:             new=88476,visited=13704,backtracked=102030,end=1\nsearch:             maxDepth=150,constraints=62360\nchoice generators:  thread=34171 (signal=0,lock=4,sharedRef=20847,threadApi=365,reschedule=18), data=0\nheap:               new=2177,released=2879,maxLive=721,gcCycles=101821\ninstructions:       3799942\nmax memory:         1010MB\nloaded code:        classes=136,methods=2412\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.54%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.54%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TravelerSleep@1c3.asleep   pool-1-t...\"\n\n====================================================== statistics\nstates:             new=86231,visited=13341,backtracked=99422,end=1\nsearch:             maxDepth=150,constraints=60775\nchoice generators:  thread=33305 (signal=0,lock=4,sharedRef=20309,threadApi=358,reschedule=21), data=0\nheap:               new=2145,released=2711,maxLive=721,gcCycles=99217\ninstructions:       3692934\nmax memory:         1010MB\nloaded code:        classes=136,methods=2412\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TravelerSleep@1c3.asleep   pool-1-t...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TravelerSleep@1c3.asleep   pool-1-t...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TravelerSleep@1c3.asleep   pool-1-t...\""
        ],
        "codebleu_score": [
            66.0,
            66.0,
            66.0
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TravelerSleep {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Traveler has fallen asleep\");\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Counting lanterns...\");\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        asleep = true;\n        System.out.println(\"Setting asleep to true\");\n    }\n    \n    public static void main(String[] args) {\n        TravelerSleep traveler = new TravelerSleep();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> traveler.tryToSleep());\n        executor.submit(() -> traveler.fallAsleep());\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TravelerSleep {\n    \n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Traveler has fallen asleep\");\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Tallying lanterns...\");\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        asleep = true;\n        System.out.println(\"Setting asleep to true\");\n    }\n    \n    public static void main(String[] args) {\n        TravelerSleep traveler = new TravelerSleep();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> traveler.tryToSleep());\n        executor.submit(() -> traveler.fallAsleep());\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TravelerSleep {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Traveler has fallen asleep\");\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Counting lanterns...\");\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        asleep = true;\n        System.out.println(\"Setting asleep to true\");\n    }\n    \n    public static void main(String[] args) {\n        TravelerSleep traveler = new TravelerSleep();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> traveler.tryToSleep());\n        executor.submit(() -> traveler.fallAsleep());\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Counting sheep. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that portrays a wanderer attempting to drift into rest by repeatedly surveying comets. The program should include a class with a volatile boolean variable called \"asleep\" to indicate whether the wanderer is asleep. It should also have a method named \"tryToSleep\" which contains a loop that continues as long as \"asleep\" is false. Inside the loop, it should call another method named \"countSomeSheep\". Implement the \"countSomeSheep\" method to represent the action of surveying comets, though its exact implementation can be left empty or contain a simple remark indicating the surveying action. The requirements are as follows:\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class WandererProgram {\n    public static void main(String[] args) throws InterruptedException {\n        Wanderer wanderer = new Wanderer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            wanderer.tryToSleep();\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(3000);\n                wanderer.fallAsleep();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nclass Wanderer {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Wanderer has fallen asleep\");\n    }\n    \n    public void countSomeSheep() {\n        System.out.println(\"Surveying comets...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class WandererProgram {\n    \n    public static void main(String[] args) throws InterruptedException {\n        Wanderer wanderer = new Wanderer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            wanderer.tryToSleep();\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(3000);\n                wanderer.fallAsleep();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nclass Wanderer {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Wanderer has fallen asleep\");\n    }\n    \n    public void countSomeSheep() {\n        System.out.println(\"Surveying comets...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class WandererProgram {\n    public static void main(String[] args) throws InterruptedException {\n        Wanderer wanderer = new Wanderer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            wanderer.tryToSleep();\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(3000);\n                wanderer.fallAsleep();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nclass Wanderer {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"The wanderer has fallen asleep.\");\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Surveying comets...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "public class CountingSheep {\n  private boolean asleep;\n\n  synchronized void tryToSleep() {\n    while (!isAsleep()) {\n      countSomeSheep();\n    }\n  }\n\n  synchronized boolean isAsleep() {\n    return asleep;\n  }\n\n  synchronized void setAsleep(boolean value) {\n    asleep = value;\n  }\n\n  void countSomeSheep() {\n    System.out.println(\"Counting sheep...\");\n    try {\n      Thread.sleep(100);\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n  }\n\n  public static void main(String[] args) {\n    CountingSheep counter = new CountingSheep();\n\n    Thread sheepThread = new Thread(() -> {\n      System.out.println(\"Sheep is trying to sleep...\");\n      counter.tryToSleep();\n      System.out.println(\"Sheep has fallen asleep.\");\n    });\n\n    Thread controllerThread = new Thread(() -> {\n      try {\n        Thread.sleep(200);\n        System.out.println(\"Setting asleep = true\");\n        counter.setAsleep(true);\n      } catch (InterruptedException e) {\n        Thread.currentThread().interrupt();\n      }\n    });\n\n    sheepThread.start();\n    controllerThread.start();\n\n    try {\n      sheepThread.join();\n      controllerThread.join();\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n\n    System.out.println(\"Main thread finished.\");\n  }\n}",
        "max_depth": "15",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.61%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.61%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field Wanderer@1c6.asleep   pool-1-thread...\"\n\n====================================================== statistics\nstates:             new=180536,visited=27206,backtracked=207592,end=0\nsearch:             maxDepth=150,constraints=127698\nchoice generators:  thread=69357 (signal=0,lock=4,sharedRef=41945,threadApi=963,reschedule=31), data=0\nheap:               new=3602,released=2342,maxLive=724,gcCycles=206827\ninstructions:       7304296\nmax memory:         1016MB\nloaded code:        classes=135,methods=2395\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.61%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.61%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field Wanderer@1c6.asleep   pool-1-thread...\"\n\n====================================================== statistics\nstates:             new=181745,visited=27368,backtracked=208963,end=0\nsearch:             maxDepth=150,constraints=128553\nchoice generators:  thread=69811 (signal=0,lock=4,sharedRef=42221,threadApi=967,reschedule=29), data=0\nheap:               new=3610,released=2366,maxLive=724,gcCycles=208190\ninstructions:       7349770\nmax memory:         1016MB\nloaded code:        classes=135,methods=2395\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.61%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.61%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field Wanderer@1c6.asleep   pool-1-thread...\"\n\n====================================================== statistics\nstates:             new=179369,visited=27048,backtracked=206267,end=0\nsearch:             maxDepth=150,constraints=126855\nchoice generators:  thread=68913 (signal=0,lock=4,sharedRef=41687,threadApi=956,reschedule=25), data=0\nheap:               new=3614,released=2438,maxLive=724,gcCycles=205508\ninstructions:       7261137\nmax memory:         1016MB\nloaded code:        classes=135,methods=2395\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field Wanderer@1c6.asleep   pool-1-thread...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field Wanderer@1c6.asleep   pool-1-thread...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field Wanderer@1c6.asleep   pool-1-thread...\""
        ],
        "codebleu_score": [
            62.37,
            62.37,
            62.37
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class WandererProgram {\n    public static void main(String[] args) throws InterruptedException {\n        Wanderer wanderer = new Wanderer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            wanderer.tryToSleep();\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(3000);\n                wanderer.fallAsleep();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nclass Wanderer {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Wanderer has fallen asleep\");\n    }\n    \n    public void countSomeSheep() {\n        System.out.println(\"Surveying comets...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class WandererProgram {\n    \n    public static void main(String[] args) throws InterruptedException {\n        Wanderer wanderer = new Wanderer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            wanderer.tryToSleep();\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(3000);\n                wanderer.fallAsleep();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nclass Wanderer {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"Wanderer has fallen asleep\");\n    }\n    \n    public void countSomeSheep() {\n        System.out.println(\"Surveying comets...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class WandererProgram {\n    public static void main(String[] args) throws InterruptedException {\n        Wanderer wanderer = new Wanderer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            wanderer.tryToSleep();\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(3000);\n                wanderer.fallAsleep();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nclass Wanderer {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n        System.out.println(\"The wanderer has fallen asleep.\");\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Surveying comets...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Counting sheep. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that depicts a scout attempting to drift into calm by repeatedly observing fireflies. The program should include a class with a volatile boolean variable called \"asleep\" to indicate whether the scout is asleep. It should also have a method named \"tryToSleep\" which contains a loop that continues as long as \"asleep\" is false. Inside the loop, it should call another method named \"countSomeSheep\". Implement the \"countSomeSheep\" method to represent the action of observing fireflies, though its exact implementation can be left empty or contain a simple note indicating the observing action. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ScoutFireflyObserver {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n    \n    public static void main(String[] args) {\n        ScoutFireflyObserver scout = new ScoutFireflyObserver();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            scout.tryToSleep();\n            System.out.println(\"Scout has fallen asleep\");\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(2000);\n                scout.fallAsleep();\n                System.out.println(\"Fireflies have calmed the scout\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ScoutFireflyObserver {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Observing fireflies...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n    \n    public static void main(String[] args) {\n        ScoutFireflyObserver scout = new ScoutFireflyObserver();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            scout.tryToSleep();\n            System.out.println(\"Scout has fallen asleep\");\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(3000);\n                scout.fallAsleep();\n                System.out.println(\"Time to sleep signaled\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ScoutFireflyObserver {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n    \n    public static void main(String[] args) {\n        ScoutFireflyObserver scout = new ScoutFireflyObserver();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            scout.tryToSleep();\n            System.out.println(\"Scout has fallen asleep\");\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(2000);\n                scout.fallAsleep();\n                System.out.println(\"Fireflies have calmed the scout\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "public class CountingSheep {\n  private boolean asleep;\n\n  synchronized void tryToSleep() {\n    while (!isAsleep()) {\n      countSomeSheep();\n    }\n  }\n\n  synchronized boolean isAsleep() {\n    return asleep;\n  }\n\n  synchronized void setAsleep(boolean value) {\n    asleep = value;\n  }\n\n  void countSomeSheep() {\n    System.out.println(\"Counting sheep...\");\n    try {\n      Thread.sleep(100);\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n  }\n\n  public static void main(String[] args) {\n    CountingSheep counter = new CountingSheep();\n\n    Thread sheepThread = new Thread(() -> {\n      System.out.println(\"Sheep is trying to sleep...\");\n      counter.tryToSleep();\n      System.out.println(\"Sheep has fallen asleep.\");\n    });\n\n    Thread controllerThread = new Thread(() -> {\n      try {\n        Thread.sleep(200);\n        System.out.println(\"Setting asleep = true\");\n        counter.setAsleep(true);\n      } catch (InterruptedException e) {\n        Thread.currentThread().interrupt();\n      }\n    });\n\n    sheepThread.start();\n    controllerThread.start();\n\n    try {\n      sheepThread.join();\n      controllerThread.join();\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n\n    System.out.println(\"Main thread finished.\");\n  }\n}",
        "max_depth": "15",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nScoutFireflyObserver.main()\n====================================================== search started: 11/16/25 4:14 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nScoutFireflyObserver.main()\n====================================================== search started: 11/16/25 4:14 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nScoutFireflyObserver.main()\n====================================================== search started: 11/16/25 4:14 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            64.92,
            66.0,
            64.92
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ScoutFireflyObserver {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n    \n    public static void main(String[] args) {\n        ScoutFireflyObserver scout = new ScoutFireflyObserver();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            scout.tryToSleep();\n            System.out.println(\"Scout has fallen asleep\");\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(2000);\n                scout.fallAsleep();\n                System.out.println(\"Fireflies have calmed the scout\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ScoutFireflyObserver {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        System.out.println(\"Observing fireflies...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n    \n    public static void main(String[] args) {\n        ScoutFireflyObserver scout = new ScoutFireflyObserver();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            scout.tryToSleep();\n            System.out.println(\"Scout has fallen asleep\");\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(3000);\n                scout.fallAsleep();\n                System.out.println(\"Time to sleep signaled\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ScoutFireflyObserver {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n    \n    public static void main(String[] args) {\n        ScoutFireflyObserver scout = new ScoutFireflyObserver();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            scout.tryToSleep();\n            System.out.println(\"Scout has fallen asleep\");\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(2000);\n                scout.fallAsleep();\n                System.out.println(\"Fireflies have calmed the scout\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Immutable class built out of mutable underlying objects. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named CosmicCats that represents an immutable bundle of identifiers belonging to the Cosmic Cats (Whiskers, Paws, and Claw). The class should use a Set internally to harbor these identifiers and provide a method to determine if a given identifier is one of the Cats. Additionally, include a method that returns a string display of all Cat identifiers in list format. Ensure that the internal bundle remains immutable from the outside, even though it is built using mutable objects. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to execute tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually handle at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class CosmicCats {\n    private final Set<String> catIdentifiers;\n    \n    public CosmicCats() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Whiskers\");\n        temp.add(\"Paws\");\n        temp.add(\"Claw\");\n        this.catIdentifiers = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isCat(String identifier) {\n        return catIdentifiers.contains(identifier);\n    }\n    \n    public String display() {\n        return catIdentifiers.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        CosmicCats cosmicCats = new CosmicCats();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkTask1 = executor.submit(() -> {\n            boolean result = cosmicCats.isCat(\"Whiskers\");\n            System.out.println(\"Thread 1: Checking 'Whiskers' - \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkTask2 = executor.submit(() -> {\n            boolean result = cosmicCats.isCat(\"Dog\");\n            System.out.println(\"Thread 2: Checking 'Dog' - \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread: All Cat identifiers - \" + cosmicCats.display());\n        \n        Boolean result1 = checkTask1.get();\n        Boolean result2 = checkTask2.get();\n        \n        System.out.println(\"Main thread: Task 1 result - \" + result1);\n        System.out.println(\"Main thread: Task 2 result - \" + result2);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class CosmicCats {\n    private final Set<String> catIdentifiers;\n    \n    public CosmicCats() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Whiskers\");\n        temp.add(\"Paws\");\n        temp.add(\"Claw\");\n        this.catIdentifiers = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isCat(String identifier) {\n        return catIdentifiers.contains(identifier);\n    }\n    \n    public String getDisplay() {\n        StringBuilder sb = new StringBuilder(\"[\");\n        Iterator<String> iterator = catIdentifiers.iterator();\n        while (iterator.hasNext()) {\n            sb.append(iterator.next());\n            if (iterator.hasNext()) {\n                sb.append(\", \");\n            }\n        }\n        sb.append(\"]\");\n        return sb.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        CosmicCats cosmicCats = new CosmicCats();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<String> displayTask = executor.submit(() -> {\n            return cosmicCats.getDisplay();\n        });\n        \n        Future<Boolean> checkTask = executor.submit(() -> {\n            boolean result1 = cosmicCats.isCat(\"Whiskers\");\n            boolean result2 = cosmicCats.isCat(\"Dog\");\n            boolean result3 = cosmicCats.isCat(\"Paws\");\n            System.out.println(\"Is 'Whiskers' a cat? \" + result1);\n            System.out.println(\"Is 'Dog' a cat? \" + result2);\n            System.out.println(\"Is 'Paws' a cat? \" + result3);\n            return result1 && !result2 && result3;\n        });\n        \n        String display = displayTask.get();\n        System.out.println(\"Cosmic Cats: \" + display);\n        \n        Boolean checkResult = checkTask.get();\n        System.out.println(\"Validation passed: \" + checkResult);\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class CosmicCats {\n    private final Set<String> catIdentifiers;\n    \n    public CosmicCats() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Whiskers\");\n        temp.add(\"Paws\");\n        temp.add(\"Claw\");\n        this.catIdentifiers = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isCat(String identifier) {\n        return catIdentifiers.contains(identifier);\n    }\n    \n    public String getDisplay() {\n        StringBuilder sb = new StringBuilder(\"[\");\n        Iterator<String> it = catIdentifiers.iterator();\n        while (it.hasNext()) {\n            sb.append(it.next());\n            if (it.hasNext()) {\n                sb.append(\", \");\n            }\n        }\n        sb.append(\"]\");\n        return sb.toString();\n    }\n    \n    public static void main(String[] args) {\n        CosmicCats cosmicCats = new CosmicCats();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<String> displayFuture = executor.submit(() -> {\n            return cosmicCats.getDisplay();\n        });\n        \n        Future<Boolean> checkFuture = executor.submit(() -> {\n            boolean result1 = cosmicCats.isCat(\"Whiskers\");\n            boolean result2 = cosmicCats.isCat(\"Fluffy\");\n            boolean result3 = cosmicCats.isCat(\"Paws\");\n            System.out.println(\"Whiskers is a Cat: \" + result1);\n            System.out.println(\"Fluffy is a Cat: \" + result2);\n            System.out.println(\"Paws is a Cat: \" + result3);\n            return result1 && result3 && !result2;\n        });\n        \n        try {\n            String display = displayFuture.get();\n            System.out.println(\"All Cat identifiers: \" + display);\n            \n            Boolean checkResult = checkFuture.get();\n            System.out.println(\"Check results valid: \" + checkResult);\n        } catch (InterruptedException | ExecutionException e) {\n            e.printStackTrace();\n        } finally {\n            executor.shutdown();\n            try {\n                if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                    executor.shutdownNow();\n                }\n            } catch (InterruptedException e) {\n                executor.shutdownNow();\n            }\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\n/**\n* ThreeStooges\n*\n* A truly immutable class using an unmodifiable set,\n* suitable for safe concurrent access and model checking with JPF.\n*/\npublic final class ThreeStooges {\nprivate final Set<String> stooges;\n\npublic ThreeStooges() {\nSet<String> temp = new HashSet<>();\ntemp.add(\"Moe\");\ntemp.add(\"Larry\");\ntemp.add(\"Curly\");\nthis.stooges = Collections.unmodifiableSet(temp);\n}\n\npublic boolean isStooge(String name) {\nreturn stooges.contains(name);\n}\n\npublic String getStoogeNames() {\n// This method returns a string representation of the stooge names\nreturn new ArrayList<>(stooges).toString();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nThreeStooges threeStooges = new ThreeStooges();\n\nThread t1 = new Thread(() -> {\nString[] names = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\"};\nfor (String name : names) {\nboolean result = threeStooges.isStooge(name);\nSystem.out.println(\"Thread-1: isStooge(\" + name + \") = \" + result);\n}\nSystem.out.println(\"Thread-1: Stooge names: \" + threeStooges.getStoogeNames());\n});\n\nThread t2 = new Thread(() -> {\nString[] names = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\"};\nfor (String name : names) {\nboolean result = threeStooges.isStooge(name);\nSystem.out.println(\"Thread-2: isStooge(\" + name + \") = \" + result);\n}\nSystem.out.println(\"Thread-2: Stooge names: \" + threeStooges.getStoogeNames());\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All threads have finished execution.\");\n}\n}",
        "max_depth": "97",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.13%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 25.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.58%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=124393,visited=86875,backtracked=210583,end=46075\nsearch:             maxDepth=970,constraints=4069\nchoice generators:  thread=121636 (signal=0,lock=4,sharedRef=49539,threadApi=2,reschedule=64520), data=0\nheap:               new=613073,released=2816580,maxLive=760,gcCycles=211268\ninstructions:       90928369\nmax memory:         1013MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 61.39%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 61.09%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 62.03%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=55518,visited=96734,backtracked=152252,end=253\nsearch:             maxDepth=113,constraints=0\nchoice generators:  thread=55514 (signal=0,lock=4765,sharedRef=37598,threadApi=579,reschedule=6481), data=0\nheap:               new=210405,released=150718,maxLive=759,gcCycles=144531\ninstructions:       10534543\nmax memory:         1012MB\nloaded code:        classes=143,methods=2471\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.42%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 18.38%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 35.66%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=131529,visited=85291,backtracked=215852,end=44308\nsearch:             maxDepth=970,constraints=10872\nchoice generators:  thread=125135 (signal=0,lock=10,sharedRef=58692,threadApi=2,reschedule=56983), data=0\nheap:               new=544853,released=2676221,maxLive=784,gcCycles=216818\ninstructions:       79599498\nmax memory:         1015MB\nloaded code:        classes=144,methods=2521\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            51.65,
            53.15,
            50.37
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class CosmicCats {\n    private final Set<String> catIdentifiers;\n    \n    public CosmicCats() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Whiskers\");\n        temp.add(\"Paws\");\n        temp.add(\"Claw\");\n        this.catIdentifiers = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isCat(String identifier) {\n        return catIdentifiers.contains(identifier);\n    }\n    \n    public String display() {\n        return catIdentifiers.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        CosmicCats cosmicCats = new CosmicCats();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkTask1 = executor.submit(() -> {\n            boolean result = cosmicCats.isCat(\"Whiskers\");\n            System.out.println(\"Thread 1: Checking 'Whiskers' - \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkTask2 = executor.submit(() -> {\n            boolean result = cosmicCats.isCat(\"Dog\");\n            System.out.println(\"Thread 2: Checking 'Dog' - \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread: All Cat identifiers - \" + cosmicCats.display());\n        \n        Boolean result1 = checkTask1.get();\n        Boolean result2 = checkTask2.get();\n        \n        System.out.println(\"Main thread: Task 1 result - \" + result1);\n        System.out.println(\"Main thread: Task 2 result - \" + result2);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class CosmicCats {\n    private final Set<String> catIdentifiers;\n    \n    public CosmicCats() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Whiskers\");\n        temp.add(\"Paws\");\n        temp.add(\"Claw\");\n        this.catIdentifiers = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isCat(String identifier) {\n        return catIdentifiers.contains(identifier);\n    }\n    \n    public String getDisplay() {\n        StringBuilder sb = new StringBuilder(\"[\");\n        Iterator<String> iterator = catIdentifiers.iterator();\n        while (iterator.hasNext()) {\n            sb.append(iterator.next());\n            if (iterator.hasNext()) {\n                sb.append(\", \");\n            }\n        }\n        sb.append(\"]\");\n        return sb.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        CosmicCats cosmicCats = new CosmicCats();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<String> displayTask = executor.submit(() -> {\n            return cosmicCats.getDisplay();\n        });\n        \n        Future<Boolean> checkTask = executor.submit(() -> {\n            boolean result1 = cosmicCats.isCat(\"Whiskers\");\n            boolean result2 = cosmicCats.isCat(\"Dog\");\n            boolean result3 = cosmicCats.isCat(\"Paws\");\n            System.out.println(\"Is 'Whiskers' a cat? \" + result1);\n            System.out.println(\"Is 'Dog' a cat? \" + result2);\n            System.out.println(\"Is 'Paws' a cat? \" + result3);\n            return result1 && !result2 && result3;\n        });\n        \n        String display = displayTask.get();\n        System.out.println(\"Cosmic Cats: \" + display);\n        \n        Boolean checkResult = checkTask.get();\n        System.out.println(\"Validation passed: \" + checkResult);\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class CosmicCats {\n    private final Set<String> catIdentifiers;\n    \n    public CosmicCats() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Whiskers\");\n        temp.add(\"Paws\");\n        temp.add(\"Claw\");\n        this.catIdentifiers = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isCat(String identifier) {\n        return catIdentifiers.contains(identifier);\n    }\n    \n    public String getDisplay() {\n        StringBuilder sb = new StringBuilder(\"[\");\n        Iterator<String> it = catIdentifiers.iterator();\n        while (it.hasNext()) {\n            sb.append(it.next());\n            if (it.hasNext()) {\n                sb.append(\", \");\n            }\n        }\n        sb.append(\"]\");\n        return sb.toString();\n    }\n    \n    public static void main(String[] args) {\n        CosmicCats cosmicCats = new CosmicCats();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<String> displayFuture = executor.submit(() -> {\n            return cosmicCats.getDisplay();\n        });\n        \n        Future<Boolean> checkFuture = executor.submit(() -> {\n            boolean result1 = cosmicCats.isCat(\"Whiskers\");\n            boolean result2 = cosmicCats.isCat(\"Fluffy\");\n            boolean result3 = cosmicCats.isCat(\"Paws\");\n            System.out.println(\"Whiskers is a Cat: \" + result1);\n            System.out.println(\"Fluffy is a Cat: \" + result2);\n            System.out.println(\"Paws is a Cat: \" + result3);\n            return result1 && result3 && !result2;\n        });\n        \n        try {\n            String display = displayFuture.get();\n            System.out.println(\"All Cat identifiers: \" + display);\n            \n            Boolean checkResult = checkFuture.get();\n            System.out.println(\"Check results valid: \" + checkResult);\n        } catch (InterruptedException | ExecutionException e) {\n            e.printStackTrace();\n        } finally {\n            executor.shutdown();\n            try {\n                if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                    executor.shutdownNow();\n                }\n            } catch (InterruptedException e) {\n                executor.shutdownNow();\n            }\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Immutable class built out of mutable underlying objects. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named MysticMonkeys that represents an immutable collection of labels belonging to the Mystic Monkeys (Banana, Coco, and Mango). The class should use a Set internally to store these labels and provide a method to check if a given label is one of the Monkeys. Additionally, include a method that returns a string representation of all Monkey labels in list format. Ensure that the internal collection remains immutable from the outside, even though it is built using mutable objects. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to execute tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticMonkeys {\n    private final Set<String> monkeyLabels;\n    \n    public MysticMonkeys() {\n        Set<String> labels = new HashSet<>();\n        labels.add(\"Banana\");\n        labels.add(\"Coco\");\n        labels.add(\"Mango\");\n        this.monkeyLabels = Collections.unmodifiableSet(labels);\n    }\n    \n    public boolean isMonkey(String label) {\n        return monkeyLabels.contains(label);\n    }\n    \n    public String getMonkeyLabelsAsString() {\n        return monkeyLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        MysticMonkeys mysticMonkeys = new MysticMonkeys();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkBanana = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Banana\");\n            return mysticMonkeys.isMonkey(\"Banana\");\n        });\n        \n        Future<Boolean> checkApple = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Apple\");\n            return mysticMonkeys.isMonkey(\"Apple\");\n        });\n        \n        System.out.println(\"Main thread: All Monkey labels: \" + mysticMonkeys.getMonkeyLabelsAsString());\n        \n        System.out.println(\"Is Banana a Monkey? \" + checkBanana.get());\n        System.out.println(\"Is Apple a Monkey? \" + checkApple.get());\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticMonkeys {\n    private final Set<String> monkeyLabels;\n    \n    public MysticMonkeys() {\n        Set<String> labels = new HashSet<>();\n        labels.add(\"Banana\");\n        labels.add(\"Coco\");\n        labels.add(\"Mango\");\n        this.monkeyLabels = Collections.unmodifiableSet(labels);\n    }\n    \n    public boolean isMonkey(String label) {\n        return monkeyLabels.contains(label);\n    }\n    \n    public String getMonkeyLabelsAsString() {\n        return monkeyLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        MysticMonkeys mysticMonkeys = new MysticMonkeys();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkBanana = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Banana\");\n            return mysticMonkeys.isMonkey(\"Banana\");\n        });\n        \n        Future<Boolean> checkApple = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Apple\");\n            return mysticMonkeys.isMonkey(\"Apple\");\n        });\n        \n        System.out.println(\"Main thread: All Monkey labels: \" + mysticMonkeys.getMonkeyLabelsAsString());\n        System.out.println(\"Is 'Banana' a Monkey? \" + checkBanana.get());\n        System.out.println(\"Is 'Apple' a Monkey? \" + checkApple.get());\n        System.out.println(\"Is 'Coco' a Monkey? \" + mysticMonkeys.isMonkey(\"Coco\"));\n        System.out.println(\"Is 'Mango' a Monkey? \" + mysticMonkeys.isMonkey(\"Mango\"));\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticMonkeys {\n    private final Set<String> monkeyLabels;\n    \n    public MysticMonkeys() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Banana\");\n        temp.add(\"Coco\");\n        temp.add(\"Mango\");\n        this.monkeyLabels = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isMonkey(String label) {\n        return monkeyLabels.contains(label);\n    }\n    \n    public String getMonkeyLabelsAsString() {\n        return monkeyLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        MysticMonkeys mysticMonkeys = new MysticMonkeys();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkBanana = executor.submit(() -> {\n            boolean result = mysticMonkeys.isMonkey(\"Banana\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" - Is 'Banana' a monkey? \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkApple = executor.submit(() -> {\n            boolean result = mysticMonkeys.isMonkey(\"Apple\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" - Is 'Apple' a monkey? \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread - All monkey labels: \" + mysticMonkeys.getMonkeyLabelsAsString());\n        \n        Boolean bananaResult = checkBanana.get();\n        Boolean appleResult = checkApple.get();\n        \n        System.out.println(\"Main thread - Final results: Banana=\" + bananaResult + \", Apple=\" + appleResult);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\n/**\n* ThreeStooges\n*\n* A truly immutable class using an unmodifiable set,\n* suitable for safe concurrent access and model checking with JPF.\n*/\npublic final class ThreeStooges {\nprivate final Set<String> stooges;\n\npublic ThreeStooges() {\nSet<String> temp = new HashSet<>();\ntemp.add(\"Moe\");\ntemp.add(\"Larry\");\ntemp.add(\"Curly\");\nthis.stooges = Collections.unmodifiableSet(temp);\n}\n\npublic boolean isStooge(String name) {\nreturn stooges.contains(name);\n}\n\npublic String getStoogeNames() {\n// This method returns a string representation of the stooge names\nreturn new ArrayList<>(stooges).toString();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nThreeStooges threeStooges = new ThreeStooges();\n\nThread t1 = new Thread(() -> {\nString[] names = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\"};\nfor (String name : names) {\nboolean result = threeStooges.isStooge(name);\nSystem.out.println(\"Thread-1: isStooge(\" + name + \") = \" + result);\n}\nSystem.out.println(\"Thread-1: Stooge names: \" + threeStooges.getStoogeNames());\n});\n\nThread t2 = new Thread(() -> {\nString[] names = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\"};\nfor (String name : names) {\nboolean result = threeStooges.isStooge(name);\nSystem.out.println(\"Thread-2: isStooge(\" + name + \") = \" + result);\n}\nSystem.out.println(\"Thread-2: Stooge names: \" + threeStooges.getStoogeNames());\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All threads have finished execution.\");\n}\n}",
        "max_depth": "97",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.32%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 25.82%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 32.02%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=118803,visited=83787,backtracked=201764,end=43381\nsearch:             maxDepth=970,constraints=3965\nchoice generators:  thread=116116 (signal=0,lock=4,sharedRef=47495,threadApi=2,reschedule=61448), data=0\nheap:               new=592601,released=2645531,maxLive=762,gcCycles=202590\ninstructions:       87070287\nmax memory:         1010MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 62.17%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 60.33%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.53%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=68083,visited=117766,backtracked=185849,end=253\nsearch:             maxDepth=96,constraints=0\nchoice generators:  thread=68079 (signal=0,lock=8095,sharedRef=43298,threadApi=487,reschedule=6188), data=0\nheap:               new=299816,released=195214,maxLive=763,gcCycles=179887\ninstructions:       13583997\nmax memory:         1014MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.15%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 25.62%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.70%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=122216,visited=85439,backtracked=206736,end=44986\nsearch:             maxDepth=970,constraints=4037\nchoice generators:  thread=119482 (signal=0,lock=4,sharedRef=48919,threadApi=2,reschedule=63109), data=0\nheap:               new=601350,released=2732696,maxLive=762,gcCycles=207655\ninstructions:       89144905\nmax memory:         1013MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            56.95,
            56.95,
            59.65
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticMonkeys {\n    private final Set<String> monkeyLabels;\n    \n    public MysticMonkeys() {\n        Set<String> labels = new HashSet<>();\n        labels.add(\"Banana\");\n        labels.add(\"Coco\");\n        labels.add(\"Mango\");\n        this.monkeyLabels = Collections.unmodifiableSet(labels);\n    }\n    \n    public boolean isMonkey(String label) {\n        return monkeyLabels.contains(label);\n    }\n    \n    public String getMonkeyLabelsAsString() {\n        return monkeyLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        MysticMonkeys mysticMonkeys = new MysticMonkeys();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkBanana = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Banana\");\n            return mysticMonkeys.isMonkey(\"Banana\");\n        });\n        \n        Future<Boolean> checkApple = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Apple\");\n            return mysticMonkeys.isMonkey(\"Apple\");\n        });\n        \n        System.out.println(\"Main thread: All Monkey labels: \" + mysticMonkeys.getMonkeyLabelsAsString());\n        \n        System.out.println(\"Is Banana a Monkey? \" + checkBanana.get());\n        System.out.println(\"Is Apple a Monkey? \" + checkApple.get());\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticMonkeys {\n    private final Set<String> monkeyLabels;\n    \n    public MysticMonkeys() {\n        Set<String> labels = new HashSet<>();\n        labels.add(\"Banana\");\n        labels.add(\"Coco\");\n        labels.add(\"Mango\");\n        this.monkeyLabels = Collections.unmodifiableSet(labels);\n    }\n    \n    public boolean isMonkey(String label) {\n        return monkeyLabels.contains(label);\n    }\n    \n    public String getMonkeyLabelsAsString() {\n        return monkeyLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        MysticMonkeys mysticMonkeys = new MysticMonkeys();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkBanana = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Banana\");\n            return mysticMonkeys.isMonkey(\"Banana\");\n        });\n        \n        Future<Boolean> checkApple = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Apple\");\n            return mysticMonkeys.isMonkey(\"Apple\");\n        });\n        \n        System.out.println(\"Main thread: All Monkey labels: \" + mysticMonkeys.getMonkeyLabelsAsString());\n        System.out.println(\"Is 'Banana' a Monkey? \" + checkBanana.get());\n        System.out.println(\"Is 'Apple' a Monkey? \" + checkApple.get());\n        System.out.println(\"Is 'Coco' a Monkey? \" + mysticMonkeys.isMonkey(\"Coco\"));\n        System.out.println(\"Is 'Mango' a Monkey? \" + mysticMonkeys.isMonkey(\"Mango\"));\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticMonkeys {\n    private final Set<String> monkeyLabels;\n    \n    public MysticMonkeys() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Banana\");\n        temp.add(\"Coco\");\n        temp.add(\"Mango\");\n        this.monkeyLabels = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isMonkey(String label) {\n        return monkeyLabels.contains(label);\n    }\n    \n    public String getMonkeyLabelsAsString() {\n        return monkeyLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        MysticMonkeys mysticMonkeys = new MysticMonkeys();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkBanana = executor.submit(() -> {\n            boolean result = mysticMonkeys.isMonkey(\"Banana\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" - Is 'Banana' a monkey? \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkApple = executor.submit(() -> {\n            boolean result = mysticMonkeys.isMonkey(\"Apple\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" - Is 'Apple' a monkey? \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread - All monkey labels: \" + mysticMonkeys.getMonkeyLabelsAsString());\n        \n        Boolean bananaResult = checkBanana.get();\n        Boolean appleResult = checkApple.get();\n        \n        System.out.println(\"Main thread - Final results: Banana=\" + bananaResult + \", Apple=\" + appleResult);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Immutable class built out of mutable underlying objects. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named StellarSprites that represents an immutable collection of tags belonging to the Stellar Sprites (Flare, Glint, and Spark). The class should use a Set internally to store these tags and provide a method to verify if a given tag is one of the Sprites. Additionally, include a method that returns a string representation of all Sprite tags in list format. Ensure that the internal collection remains immutable from the outside, even though it is built using mutable objects. The requirements are as follows:\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to execute tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class StellarSprites {\n    private final Set<String> sprites;\n    \n    public StellarSprites() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Flare\");\n        temp.add(\"Glint\");\n        temp.add(\"Spark\");\n        this.sprites = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isSprite(String tag) {\n        return sprites.contains(tag);\n    }\n    \n    public String getSpritesAsString() {\n        return sprites.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        StellarSprites stellarSprites = new StellarSprites();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkFlare = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Flare\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" - Flare is sprite: \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkNova = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Nova\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" - Nova is sprite: \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread - All sprites: \" + stellarSprites.getSpritesAsString());\n        \n        Boolean flareResult = checkFlare.get();\n        Boolean novaResult = checkNova.get();\n        \n        System.out.println(\"Main thread - Final results: Flare=\" + flareResult + \", Nova=\" + novaResult);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class StellarSprites {\n    private final Set<String> sprites;\n    \n    public StellarSprites() {\n        Set<String> tempSet = new HashSet<>();\n        tempSet.add(\"Flare\");\n        tempSet.add(\"Glint\");\n        tempSet.add(\"Spark\");\n        this.sprites = Collections.unmodifiableSet(tempSet);\n    }\n    \n    public boolean isSprite(String tag) {\n        return sprites.contains(tag);\n    }\n    \n    public String getSpritesAsString() {\n        return sprites.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        StellarSprites stellarSprites = new StellarSprites();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkTask1 = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Flare\");\n            System.out.println(\"Thread 1 - Is 'Flare' a sprite? \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkTask2 = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Nova\");\n            System.out.println(\"Thread 2 - Is 'Nova' a sprite? \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread - All sprites: \" + stellarSprites.getSpritesAsString());\n        \n        Boolean result1 = checkTask1.get();\n        Boolean result2 = checkTask2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Main thread - Final check for 'Spark': \" + stellarSprites.isSprite(\"Spark\"));\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class StellarSprites {\n    private final Set<String> sprites;\n    \n    public StellarSprites() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Flare\");\n        temp.add(\"Glint\");\n        temp.add(\"Spark\");\n        this.sprites = Collections.unmodifiableSet(temp);\n    }\n    \n    public boolean isSprite(String tag) {\n        return sprites.contains(tag);\n    }\n    \n    public String getSpritesAsString() {\n        return sprites.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        StellarSprites stellarSprites = new StellarSprites();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkTask1 = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Flare\");\n            System.out.println(\"Thread 1 - Is 'Flare' a sprite? \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkTask2 = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Nova\");\n            System.out.println(\"Thread 2 - Is 'Nova' a sprite? \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread - All sprites: \" + stellarSprites.getSpritesAsString());\n        \n        Boolean result1 = checkTask1.get();\n        Boolean result2 = checkTask2.get();\n        \n        System.out.println(\"Main thread - Check for 'Glint': \" + stellarSprites.isSprite(\"Glint\"));\n        System.out.println(\"Main thread - Check for 'Spark': \" + stellarSprites.isSprite(\"Spark\"));\n        \n        executor.shutdown();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\n/**\n* ThreeStooges\n*\n* A truly immutable class using an unmodifiable set,\n* suitable for safe concurrent access and model checking with JPF.\n*/\npublic final class ThreeStooges {\nprivate final Set<String> stooges;\n\npublic ThreeStooges() {\nSet<String> temp = new HashSet<>();\ntemp.add(\"Moe\");\ntemp.add(\"Larry\");\ntemp.add(\"Curly\");\nthis.stooges = Collections.unmodifiableSet(temp);\n}\n\npublic boolean isStooge(String name) {\nreturn stooges.contains(name);\n}\n\npublic String getStoogeNames() {\n// This method returns a string representation of the stooge names\nreturn new ArrayList<>(stooges).toString();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nThreeStooges threeStooges = new ThreeStooges();\n\nThread t1 = new Thread(() -> {\nString[] names = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\"};\nfor (String name : names) {\nboolean result = threeStooges.isStooge(name);\nSystem.out.println(\"Thread-1: isStooge(\" + name + \") = \" + result);\n}\nSystem.out.println(\"Thread-1: Stooge names: \" + threeStooges.getStoogeNames());\n});\n\nThread t2 = new Thread(() -> {\nString[] names = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\"};\nfor (String name : names) {\nboolean result = threeStooges.isStooge(name);\nSystem.out.println(\"Thread-2: isStooge(\" + name + \") = \" + result);\n}\nSystem.out.println(\"Thread-2: Stooge names: \" + threeStooges.getStoogeNames());\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All threads have finished execution.\");\n}\n}",
        "max_depth": "97",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.17%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 25.54%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.69%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=122502,visited=85675,backtracked=207380,end=45157\nsearch:             maxDepth=970,constraints=4046\nchoice generators:  thread=119762 (signal=0,lock=4,sharedRef=48990,threadApi=2,reschedule=63306), data=0\nheap:               new=601622,released=2763292,maxLive=762,gcCycles=208177\ninstructions:       89395672\nmax memory:         1014MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.64%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 26.40%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 32.71%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=111068,visited=79751,backtracked=189915,end=39766\nsearch:             maxDepth=970,constraints=3732\nchoice generators:  thread=108539 (signal=0,lock=4,sharedRef=44419,threadApi=2,reschedule=57549), data=0\nheap:               new=911396,released=2653039,maxLive=758,gcCycles=190819\ninstructions:       85912674\nmax memory:         1012MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 62.18%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 60.34%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.54%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=68662,visited=118804,backtracked=187466,end=253\nsearch:             maxDepth=97,constraints=0\nchoice generators:  thread=68658 (signal=0,lock=8166,sharedRef=43678,threadApi=487,reschedule=6238), data=0\nheap:               new=274549,released=185943,maxLive=752,gcCycles=181504\ninstructions:       13481166\nmax memory:         1014MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            59.09,
            52.55,
            52.0
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class StellarSprites {\n    private final Set<String> sprites;\n    \n    public StellarSprites() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Flare\");\n        temp.add(\"Glint\");\n        temp.add(\"Spark\");\n        this.sprites = Collections.unmodifiableSet(new HashSet<>(temp));\n    }\n    \n    public boolean isSprite(String tag) {\n        return sprites.contains(tag);\n    }\n    \n    public String getSpritesAsString() {\n        return sprites.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        StellarSprites stellarSprites = new StellarSprites();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkFlare = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Flare\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" - Flare is sprite: \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkNova = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Nova\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" - Nova is sprite: \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread - All sprites: \" + stellarSprites.getSpritesAsString());\n        \n        Boolean flareResult = checkFlare.get();\n        Boolean novaResult = checkNova.get();\n        \n        System.out.println(\"Main thread - Final results: Flare=\" + flareResult + \", Nova=\" + novaResult);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class StellarSprites {\n    private final Set<String> sprites;\n    \n    public StellarSprites() {\n        Set<String> tempSet = new HashSet<>();\n        tempSet.add(\"Flare\");\n        tempSet.add(\"Glint\");\n        tempSet.add(\"Spark\");\n        this.sprites = Collections.unmodifiableSet(tempSet);\n    }\n    \n    public boolean isSprite(String tag) {\n        return sprites.contains(tag);\n    }\n    \n    public String getSpritesAsString() {\n        return sprites.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        StellarSprites stellarSprites = new StellarSprites();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkTask1 = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Flare\");\n            System.out.println(\"Thread 1 - Is 'Flare' a sprite? \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkTask2 = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Nova\");\n            System.out.println(\"Thread 2 - Is 'Nova' a sprite? \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread - All sprites: \" + stellarSprites.getSpritesAsString());\n        \n        Boolean result1 = checkTask1.get();\n        Boolean result2 = checkTask2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Main thread - Final check for 'Spark': \" + stellarSprites.isSprite(\"Spark\"));\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class StellarSprites {\n    private final Set<String> sprites;\n    \n    public StellarSprites() {\n        Set<String> temp = new HashSet<>();\n        temp.add(\"Flare\");\n        temp.add(\"Glint\");\n        temp.add(\"Spark\");\n        this.sprites = Collections.unmodifiableSet(temp);\n    }\n    \n    public boolean isSprite(String tag) {\n        return sprites.contains(tag);\n    }\n    \n    public String getSpritesAsString() {\n        return sprites.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        StellarSprites stellarSprites = new StellarSprites();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkTask1 = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Flare\");\n            System.out.println(\"Thread 1 - Is 'Flare' a sprite? \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkTask2 = executor.submit(() -> {\n            boolean result = stellarSprites.isSprite(\"Nova\");\n            System.out.println(\"Thread 2 - Is 'Nova' a sprite? \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread - All sprites: \" + stellarSprites.getSpritesAsString());\n        \n        Boolean result1 = checkTask1.get();\n        Boolean result2 = checkTask2.get();\n        \n        System.out.println(\"Main thread - Check for 'Glint': \" + stellarSprites.isSprite(\"Glint\"));\n        System.out.println(\"Main thread - Check for 'Spark': \" + stellarSprites.isSprite(\"Spark\"));\n        \n        executor.shutdown();\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Returning a static copy of the location set instead of a 'live' one. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called DelegatingDeviceTracker that monitors the positions of gadgets in a thread-safe manner using a ConcurrentHashMap. The class should provide methods to fetch the position of a specific gadget, update the position of a gadget, and return an unmodifiable view of all gadget positions. Use delegation to ensure thread safety without explicitly synchronizing methods. Initialize the tracker with a map of gadget IDs to their initial positions. Include two versions of the method to retrieve all positions: one that returns a live unmodifiable map backed by the original data, and another that returns a static snapshot of the current state as an unmodifiable map. Ensure that updating a gadget's position only succeeds if the gadget ID already exists in the map. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Position {\n    private final double x;\n    private final double y;\n    \n    public Position(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public double getX() {\n        return x;\n    }\n    \n    public double getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"Position(%.2f, %.2f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return Double.compare(position.x, x) == 0 && \n               Double.compare(position.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n\nclass DelegatingDeviceTracker {\n    private final ConcurrentHashMap<String, Position> locations;\n    private final Map<String, Position> unmodifiableMap;\n    \n    public DelegatingDeviceTracker(Map<String, Position> initialPositions) {\n        this.locations = new ConcurrentHashMap<>(initialPositions);\n        this.unmodifiableMap = Collections.unmodifiableMap(locations);\n    }\n    \n    public Position getPosition(String gadgetId) {\n        return locations.get(gadgetId);\n    }\n    \n    public boolean updatePosition(String gadgetId, Position newPosition) {\n        if (newPosition == null) {\n            throw new IllegalArgumentException(\"Position cannot be null\");\n        }\n        // Only update if the gadget ID already exists\n        return locations.replace(gadgetId, locations.get(gadgetId), newPosition) ||\n               (locations.containsKey(gadgetId) && \n                locations.replace(gadgetId, newPosition) != null);\n    }\n    \n    public Map<String, Position> getLiveUnmodifiableView() {\n        return unmodifiableMap;\n    }\n    \n    public Map<String, Position> getStaticSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(locations));\n    }\n    \n    public int getDeviceCount() {\n        return locations.size();\n    }\n}\n\npublic class DeviceTrackerDemo {\n    \n    public static void main(String[] args) {\n        // Initialize the tracker with some gadgets\n        Map<String, Position> initialPositions = new HashMap<>();\n        initialPositions.put(\"phone1\", new Position(10.0, 20.0));\n        initialPositions.put(\"tablet1\", new Position(30.0, 40.0));\n        initialPositions.put(\"laptop1\", new Position(50.0, 60.0));\n        initialPositions.put(\"watch1\", new Position(70.0, 80.0));\n        \n        DelegatingDeviceTracker tracker = new DelegatingDeviceTracker(initialPositions);\n        \n        System.out.println(\"Initial positions:\");\n        tracker.getLiveUnmodifiableView().forEach((id, pos) -> \n            System.out.println(\"  \" + id + \": \" + pos));\n        \n        // Create an ExecutorService with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Create tasks to update positions concurrently\n        Runnable updateTask1 = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String gadgetId = \"phone1\";\n                Position newPos = new Position(10.0 + i * 2, 20.0 + i * 2);\n                boolean updated = tracker.updatePosition(gadgetId, newPos);\n                if (updated) {\n                    System.out.println(threadName + \" updated \" + gadgetId + \n                                     \" to \" + newPos);\n                }\n                \n                // Also try to update a non-existent gadget (should fail)\n                boolean failedUpdate = tracker.updatePosition(\"nonexistent\", \n                                                             new Position(0, 0));\n                if (!failedUpdate && i == 0) {\n                    System.out.println(threadName + \n                                     \" correctly failed to update non-existent gadget\");\n                }\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        Runnable updateTask2 = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String gadgetId = \"tablet1\";\n                Position newPos = new Position(30.0 - i * 3, 40.0 - i * 3);\n                boolean updated = tracker.updatePosition(gadgetId, newPos);\n                if (updated) {\n                    System.out.println(threadName + \" updated \" + gadgetId + \n                                     \" to \" + newPos);\n                }\n                \n                // Read position of another gadget\n                Position laptopPos = tracker.getPosition(\"laptop1\");\n                if (i == 2) {\n                    System.out.println(threadName + \" read laptop1 position: \" + \n                                     laptopPos);\n                }\n                \n                try {\n                    Thread.sleep(120);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> future1 = executor.submit(updateTask1);\n        Future<?> future2 = executor.submit(updateTask2);\n        \n        // Main thread also performs some operations\n        System.out.println(\"\\nMain thread performing operations...\");\n        for (int i = 0; i < 3; i++) {\n            // Update laptop position from main thread\n            Position newLaptopPos = new Position(50.0 + i * 5, 60.0 + i * 5);\n            tracker.updatePosition(\"laptop1\", newLaptopPos);\n            System.out.println(\"Main thread updated laptop1 to \" + newLaptopPos);\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                break;\n            }\n        }\n        \n        // Wait for tasks to complete\n        try {\n            future1.get();\n            future2.get();\n        } catch (InterruptedException | ExecutionException e) {\n            e.printStackTrace();\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"\\nFinal positions (live view):\");\n        Map<String, Position> liveView = tracker.getLiveUnmodifiableView();\n        liveView.forEach((id, pos) -> \n            System.out.println(\"  \" + id + \": \" + pos));\n        \n        System.out.println(\"\\nTaking a snapshot...\");\n        Map<String, Position> snapshot = tracker.getStaticSnapshot();\n        \n        // Update a position after taking snapshot\n        tracker.updatePosition(\"watch1\", new Position(100.0, 110.0));\n        \n        System.out.println(\"\\nSnapshot (unchanged after update):\");\n        snapshot.forEach((id, pos) -> \n            System.out.println(\"  \" + id + \": \" + pos));\n        \n        System.out.println(\"\\nLive view (shows updated watch1):\");\n        liveView.forEach((id, pos) -> \n            System.out.println(\"  \" + id + \": \" + pos));\n        \n        // Demonstrate thread safety by trying to modify returned maps\n        try {\n            liveView.put(\"newGadget\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"\\nCorrectly prevented modification of live view\");\n        }\n        \n        try {\n            snapshot.put(\"newGadget\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Correctly prevented modification of snapshot\");\n        }\n        \n        System.out.println(\"\\nTotal devices tracked: \" + tracker.getDeviceCount());\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingDeviceTracker {\n    private final ConcurrentHashMap<String, Position> locations;\n    private final Map<String, Position> unmodifiableMap;\n\n    public DelegatingDeviceTracker(Map<String, Position> initialPositions) {\n        this.locations = new ConcurrentHashMap<>(initialPositions);\n        this.unmodifiableMap = Collections.unmodifiableMap(locations);\n    }\n\n    public Position getPosition(String gadgetId) {\n        Position pos = locations.get(gadgetId);\n        return pos == null ? null : new Position(pos);\n    }\n\n    public boolean updatePosition(String gadgetId, Position newPosition) {\n        if (newPosition == null) {\n            return false;\n        }\n        Position existingPosition = locations.get(gadgetId);\n        if (existingPosition != null) {\n            locations.put(gadgetId, new Position(newPosition));\n            return true;\n        }\n        return false;\n    }\n\n    public Map<String, Position> getLiveUnmodifiableView() {\n        return unmodifiableMap;\n    }\n\n    public Map<String, Position> getStaticSnapshot() {\n        Map<String, Position> snapshot = new HashMap<>();\n        for (Map.Entry<String, Position> entry : locations.entrySet()) {\n            snapshot.put(entry.getKey(), new Position(entry.getValue()));\n        }\n        return Collections.unmodifiableMap(snapshot);\n    }\n\n    public static void main(String[] args) {\n        // Initialize with some gadget positions\n        Map<String, Position> initialPositions = new HashMap<>();\n        initialPositions.put(\"gadget1\", new Position(10, 20));\n        initialPositions.put(\"gadget2\", new Position(30, 40));\n        initialPositions.put(\"gadget3\", new Position(50, 60));\n\n        DelegatingDeviceTracker tracker = new DelegatingDeviceTracker(initialPositions);\n\n        // Create ExecutorService with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        // Task 1: Continuously update positions\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            Random random = new Random();\n            for (int i = 0; i < 5; i++) {\n                String gadgetId = \"gadget\" + (random.nextInt(3) + 1);\n                Position newPos = new Position(random.nextInt(100), random.nextInt(100));\n                boolean updated = tracker.updatePosition(gadgetId, newPos);\n                System.out.println(\"[\" + threadName + \"] Updating \" + gadgetId + \n                                 \" to \" + newPos + \" - Success: \" + updated);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n\n        // Task 2: Continuously read positions\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String gadgetId = \"gadget\" + ((i % 3) + 1);\n                Position pos = tracker.getPosition(gadgetId);\n                System.out.println(\"[\" + threadName + \"] Reading \" + gadgetId + \n                                 \" position: \" + pos);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n\n        // Main thread operations\n        try {\n            Thread.sleep(200);\n            \n            // Try to update a non-existent gadget\n            boolean failedUpdate = tracker.updatePosition(\"gadget99\", new Position(99, 99));\n            System.out.println(\"[Main Thread] Attempt to update non-existent gadget99: \" + failedUpdate);\n            \n            // Get live view\n            Map<String, Position> liveView = tracker.getLiveUnmodifiableView();\n            System.out.println(\"[Main Thread] Live view size: \" + liveView.size());\n            \n            Thread.sleep(300);\n            \n            // Get static snapshot\n            Map<String, Position> snapshot = tracker.getStaticSnapshot();\n            System.out.println(\"[Main Thread] Snapshot of all positions:\");\n            for (Map.Entry<String, Position> entry : snapshot.entrySet()) {\n                System.out.println(\"  \" + entry.getKey() + \": \" + entry.getValue());\n            }\n            \n            // Demonstrate that snapshot is unmodifiable\n            try {\n                snapshot.put(\"newGadget\", new Position(0, 0));\n            } catch (UnsupportedOperationException e) {\n                System.out.println(\"[Main Thread] Snapshot is unmodifiable - caught expected exception\");\n            }\n            \n            // Demonstrate that live view is unmodifiable\n            try {\n                liveView.put(\"newGadget\", new Position(0, 0));\n            } catch (UnsupportedOperationException e) {\n                System.out.println(\"[Main Thread] Live view is unmodifiable - caught expected exception\");\n            }\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(2, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"\\n[Main Thread] Final positions:\");\n        Map<String, Position> finalSnapshot = tracker.getStaticSnapshot();\n        for (Map.Entry<String, Position> entry : finalSnapshot.entrySet()) {\n            System.out.println(\"  \" + entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass Position {\n    private final int x;\n    private final int y;\n\n    public Position(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public Position(Position position) {\n        this.x = position.x;\n        this.y = position.y;\n    }\n\n    public int getX() {\n        return x;\n    }\n\n    public int getY() {\n        return y;\n    }\n\n    @Override\n    public String toString() {\n        return \"Position{x=\" + x + \", y=\" + y + \"}\";\n    }\n\n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Position position = (Position) o;\n        return x == position.x && y == position.y;\n    }\n\n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingDeviceTracker {\n    private final ConcurrentHashMap<String, Position> locations;\n    private final Map<String, Position> unmodifiableMap;\n    \n    public DelegatingDeviceTracker(Map<String, Position> initialPositions) {\n        this.locations = new ConcurrentHashMap<>(initialPositions);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n    \n    // Get position of a specific gadget\n    public Position getPosition(String gadgetId) {\n        Position pos = locations.get(gadgetId);\n        return pos == null ? null : new Position(pos.getX(), pos.getY());\n    }\n    \n    // Update position of a gadget (only if it exists)\n    public boolean updatePosition(String gadgetId, int x, int y) {\n        Position newPos = new Position(x, y);\n        return locations.replace(gadgetId, locations.get(gadgetId), newPos);\n    }\n    \n    // Returns a live unmodifiable view backed by the original data\n    public Map<String, Position> getLivePositions() {\n        return unmodifiableMap;\n    }\n    \n    // Returns a static snapshot of the current state as an unmodifiable map\n    public Map<String, Position> getSnapshotPositions() {\n        Map<String, Position> snapshot = new HashMap<>();\n        for (Map.Entry<String, Position> entry : locations.entrySet()) {\n            Position pos = entry.getValue();\n            snapshot.put(entry.getKey(), new Position(pos.getX(), pos.getY()));\n        }\n        return Collections.unmodifiableMap(snapshot);\n    }\n    \n    public static void main(String[] args) {\n        // Initialize with some gadgets\n        Map<String, Position> initialPositions = new HashMap<>();\n        initialPositions.put(\"gadget1\", new Position(10, 20));\n        initialPositions.put(\"gadget2\", new Position(30, 40));\n        initialPositions.put(\"gadget3\", new Position(50, 60));\n        \n        DelegatingDeviceTracker tracker = new DelegatingDeviceTracker(initialPositions);\n        \n        // Create a fixed thread pool with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Task 1: Update positions\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            System.out.println(threadName + \" - Starting position updates\");\n            \n            for (int i = 0; i < 5; i++) {\n                boolean updated = tracker.updatePosition(\"gadget1\", \n                    10 + i * 5, 20 + i * 5);\n                System.out.println(threadName + \" - Updated gadget1: \" + updated);\n                \n                updated = tracker.updatePosition(\"gadget2\", \n                    30 + i * 3, 40 + i * 3);\n                System.out.println(threadName + \" - Updated gadget2: \" + updated);\n                \n                // Try to update non-existent gadget\n                updated = tracker.updatePosition(\"gadget99\", 100, 100);\n                System.out.println(threadName + \" - Tried to update non-existent gadget99: \" + updated);\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        // Task 2: Read positions\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            System.out.println(threadName + \" - Starting position reads\");\n            \n            for (int i = 0; i < 5; i++) {\n                Position pos1 = tracker.getPosition(\"gadget1\");\n                Position pos2 = tracker.getPosition(\"gadget2\");\n                Position pos3 = tracker.getPosition(\"gadget3\");\n                \n                System.out.println(threadName + \" - Current positions:\");\n                System.out.println(\"  gadget1: \" + pos1);\n                System.out.println(\"  gadget2: \" + pos2);\n                System.out.println(\"  gadget3: \" + pos3);\n                \n                // Get snapshot\n                Map<String, Position> snapshot = tracker.getSnapshotPositions();\n                System.out.println(threadName + \" - Snapshot size: \" + snapshot.size());\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        // Main thread also does some work\n        System.out.println(\"Main thread - Monitoring live positions\");\n        Map<String, Position> liveView = tracker.getLivePositions();\n        \n        for (int i = 0; i < 3; i++) {\n            System.out.println(\"Main thread - Live view size: \" + liveView.size());\n            System.out.println(\"Main thread - Live positions: \" + liveView);\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(2, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        // Final state\n        System.out.println(\"\\nFinal positions:\");\n        Map<String, Position> finalSnapshot = tracker.getSnapshotPositions();\n        for (Map.Entry<String, Position> entry : finalSnapshot.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass Position {\n    private final int x;\n    private final int y;\n    \n    public Position(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public int getX() {\n        return x;\n    }\n    \n    public int getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Position[x=\" + x + \", y=\" + y + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return x == position.x && y == position.y;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.awt.Point;\nimport java.util.*;\nimport java.util.concurrent.*;\n\n/**\n* DelegatingVehicleTracker\n* Delegates thread safety to a ConcurrentHashMap.\n*/\npublic class DelegatingVehicleTracker {\n\nprivate final ConcurrentMap<String, Point> locations;\nprivate final Map<String, Point> unmodifiableMap;\n\npublic DelegatingVehicleTracker(Map<String, Point> points) {\nlocations = new ConcurrentHashMap<>(points);\nunmodifiableMap = Collections.unmodifiableMap(locations);\n}\n\npublic Map<String, Point> getLocations() {\nreturn unmodifiableMap;\n}\n\n\npublic void setLocation(String id, int x, int y) {\nif (locations.replace(id, new Point(x, y)) == null)\nthrow new IllegalArgumentException(\"Invalid vehicle name: \" + id);\n}\n\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, Point> initialVehicles = new HashMap<>();\ninitialVehicles.put(\"V1\", new Point(0, 0));\ninitialVehicles.put(\"V2\", new Point(0, 0));\ninitialVehicles.put(\"V3\", new Point(0, 0));\n\nDelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialVehicles);\n\n// Reduce threads to 2 for JPF-friendly execution\nThread[] threads = new Thread[2];\n\nfor (int i = 0; i < 2; i++) {\nfinal String vehicleId = \"V\" + ((i % 3) + 1);\nthreads[i] = new Thread(() -> {\ntry {\n// Reduce iterations to 2 per thread\nfor (int j = 0; j < 2; j++) {\n// Use deterministic fixed values instead of random\nint x = j * 10 + 5;\nint y = j * 20 + 5;\ntracker.setLocation(vehicleId, x, y);\nSystem.out.println(Thread.currentThread().getName() +\n\" updated \" + vehicleId + \" to (\" + x + \", \" + y + \")\");\nThread.sleep(10);\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\ntracker.getLocations().forEach((id, point) ->\nSystem.out.println(id + \": (\" + point.x + \", \" + point.y + \")\"));\n}\n}",
        "max_depth": "57",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 53.70%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 54.69%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.50%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=97470,visited=154137,backtracked=251517,end=1061\nsearch:             maxDepth=570,constraints=8644\nchoice generators:  thread=92877 (signal=0,lock=37,sharedRef=83439,threadApi=5,reschedule=8904), data=0\nheap:               new=349864,released=513439,maxLive=907,gcCycles=246724\ninstructions:       49528664\nmax memory:         1019MB\nloaded code:        classes=164,methods=2756\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.47%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.89%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.89%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=87797,visited=119520,backtracked=206951,end=191\nsearch:             maxDepth=570,constraints=18838\nchoice generators:  thread=71555 (signal=0,lock=15,sharedRef=61083,threadApi=4,reschedule=6210), data=0\nheap:               new=442637,released=317927,maxLive=915,gcCycles=200490\ninstructions:       74124564\nmax memory:         1019MB\nloaded code:        classes=165,methods=2797\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.47%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.89%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.90%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=86461,visited=116999,backtracked=203074,end=187\nsearch:             maxDepth=570,constraints=18841\nchoice generators:  thread=70224 (signal=0,lock=17,sharedRef=59890,threadApi=5,reschedule=6071), data=0\nheap:               new=466531,released=308173,maxLive=866,gcCycles=196779\ninstructions:       72432626\nmax memory:         1017MB\nloaded code:        classes=162,methods=2772\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            61.37,
            61.51,
            62.65
        ],
        "llm_output": [
            "Here's a complete Java 8 implementation that meets all your requirements:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Position {\n    private final double x;\n    private final double y;\n    \n    public Position(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public double getX() {\n        return x;\n    }\n    \n    public double getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"Position(%.2f, %.2f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return Double.compare(position.x, x) == 0 && \n               Double.compare(position.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n\nclass DelegatingDeviceTracker {\n    private final ConcurrentHashMap<String, Position> locations;\n    private final Map<String, Position> unmodifiableMap;\n    \n    public DelegatingDeviceTracker(Map<String, Position> initialPositions) {\n        this.locations = new ConcurrentHashMap<>(initialPositions);\n        this.unmodifiableMap = Collections.unmodifiableMap(locations);\n    }\n    \n    public Position getPosition(String gadgetId) {\n        return locations.get(gadgetId);\n    }\n    \n    public boolean updatePosition(String gadgetId, Position newPosition) {\n        if (newPosition == null) {\n            throw new IllegalArgumentException(\"Position cannot be null\");\n        }\n        // Only update if the gadget ID already exists\n        return locations.replace(gadgetId, locations.get(gadgetId), newPosition) ||\n               (locations.containsKey(gadgetId) && \n                locations.replace(gadgetId, newPosition) != null);\n    }\n    \n    public Map<String, Position> getLiveUnmodifiableView() {\n        return unmodifiableMap;\n    }\n    \n    public Map<String, Position> getStaticSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(locations));\n    }\n    \n    public int getDeviceCount() {\n        return locations.size();\n    }\n}\n\npublic class DeviceTrackerDemo {\n    \n    public static void main(String[] args) {\n        // Initialize the tracker with some gadgets\n        Map<String, Position> initialPositions = new HashMap<>();\n        initialPositions.put(\"phone1\", new Position(10.0, 20.0));\n        initialPositions.put(\"tablet1\", new Position(30.0, 40.0));\n        initialPositions.put(\"laptop1\", new Position(50.0, 60.0));\n        initialPositions.put(\"watch1\", new Position(70.0, 80.0));\n        \n        DelegatingDeviceTracker tracker = new DelegatingDeviceTracker(initialPositions);\n        \n        System.out.println(\"Initial positions:\");\n        tracker.getLiveUnmodifiableView().forEach((id, pos) -> \n            System.out.println(\"  \" + id + \": \" + pos));\n        \n        // Create an ExecutorService with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Create tasks to update positions concurrently\n        Runnable updateTask1 = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String gadgetId = \"phone1\";\n                Position newPos = new Position(10.0 + i * 2, 20.0 + i * 2);\n                boolean updated = tracker.updatePosition(gadgetId, newPos);\n                if (updated) {\n                    System.out.println(threadName + \" updated \" + gadgetId + \n                                     \" to \" + newPos);\n                }\n                \n                // Also try to update a non-existent gadget (should fail)\n                boolean failedUpdate = tracker.updatePosition(\"nonexistent\", \n                                                             new Position(0, 0));\n                if (!failedUpdate && i == 0) {\n                    System.out.println(threadName + \n                                     \" correctly failed to update non-existent gadget\");\n                }\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        Runnable updateTask2 = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String gadgetId = \"tablet1\";\n                Position newPos = new Position(30.0 - i * 3, 40.0 - i * 3);\n                boolean updated = tracker.updatePosition(gadgetId, newPos);\n                if (updated) {\n                    System.out.println(threadName + \" updated \" + gadgetId + \n                                     \" to \" + newPos);\n                }\n                \n                // Read position of another gadget\n                Position laptopPos = tracker.getPosition(\"laptop1\");\n                if (i == 2) {\n                    System.out.println(threadName + \" read laptop1 position: \" + \n                                     laptopPos);\n                }\n                \n                try {\n                    Thread.sleep(120);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> future1 = executor.submit(updateTask1);\n        Future<?> future2 = executor.submit(updateTask2);\n        \n        // Main thread also performs some operations\n        System.out.println(\"\\nMain thread performing operations...\");\n        for (int i = 0; i < 3; i++) {\n            // Update laptop position from main thread\n            Position newLaptopPos = new Position(50.0 + i * 5, 60.0 + i * 5);\n            tracker.updatePosition(\"laptop1\", newLaptopPos);\n            System.out.println(\"Main thread updated laptop1 to \" + newLaptopPos);\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                break;\n            }\n        }\n        \n        // Wait for tasks to complete\n        try {\n            future1.get();\n            future2.get();\n        } catch (InterruptedException | ExecutionException e) {\n            e.printStackTrace();\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"\\nFinal positions (live view):\");\n        Map<String, Position> liveView = tracker.getLiveUnmodifiableView();\n        liveView.forEach((id, pos) -> \n            System.out.println(\"  \" + id + \": \" + pos));\n        \n        System.out.println(\"\\nTaking a snapshot...\");\n        Map<String, Position> snapshot = tracker.getStaticSnapshot();\n        \n        // Update a position after taking snapshot\n        tracker.updatePosition(\"watch1\", new Position(100.0, 110.0));\n        \n        System.out.println(\"\\nSnapshot (unchanged after update):\");\n        snapshot.forEach((id, pos) -> \n            System.out.println(\"  \" + id + \": \" + pos));\n        \n        System.out.println(\"\\nLive view (shows updated watch1):\");\n        liveView.forEach((id, pos) -> \n            System.out.println(\"  \" + id + \": \" + pos));\n        \n        // Demonstrate thread safety by trying to modify returned maps\n        try {\n            liveView.put(\"newGadget\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"\\nCorrectly prevented modification of live view\");\n        }\n        \n        try {\n            snapshot.put(\"newGadget\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Correctly prevented modification of snapshot\");\n        }\n        \n        System.out.println(\"\\nTotal devices tracked: \" + tracker.getDeviceCount());\n    }\n}\n```\n\nThis implementation provides:\n\n1. **Thread-safe device tracking** using `ConcurrentHashMap` with delegation pattern\n2. **Position class** to represent immutable gadget positions\n3. **DelegatingDeviceTracker class** with:\n   - Constructor accepting initial positions\n   - `getPosition()` to fetch a specific gadget's position\n   - `updatePosition()` that only updates existing gadgets\n   - `getLiveUnmodifiableView()` returning a live unmodifiable view\n   - `getStaticSnapshot()` returning a static snapshot\n4. **Concurrent operations** using:\n   - Main thread\n   - 2 additional worker threads via `ExecutorService`\n   - Total of 3 threads as required\n5. **Thread safety** through:\n   - `ConcurrentHashMap` for internal storage\n   - Immutable `Position` objects\n   - Unmodifiable map views\n   - No explicit synchronization needed due to delegation\n\nThe program demonstrates concurrent updates from multiple threads while maintaining thread safety and data consistency.",
            "Here's a complete Java 8 implementation that meets all your requirements:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingDeviceTracker {\n    private final ConcurrentHashMap<String, Position> locations;\n    private final Map<String, Position> unmodifiableMap;\n\n    public DelegatingDeviceTracker(Map<String, Position> initialPositions) {\n        this.locations = new ConcurrentHashMap<>(initialPositions);\n        this.unmodifiableMap = Collections.unmodifiableMap(locations);\n    }\n\n    public Position getPosition(String gadgetId) {\n        Position pos = locations.get(gadgetId);\n        return pos == null ? null : new Position(pos);\n    }\n\n    public boolean updatePosition(String gadgetId, Position newPosition) {\n        if (newPosition == null) {\n            return false;\n        }\n        Position existingPosition = locations.get(gadgetId);\n        if (existingPosition != null) {\n            locations.put(gadgetId, new Position(newPosition));\n            return true;\n        }\n        return false;\n    }\n\n    public Map<String, Position> getLiveUnmodifiableView() {\n        return unmodifiableMap;\n    }\n\n    public Map<String, Position> getStaticSnapshot() {\n        Map<String, Position> snapshot = new HashMap<>();\n        for (Map.Entry<String, Position> entry : locations.entrySet()) {\n            snapshot.put(entry.getKey(), new Position(entry.getValue()));\n        }\n        return Collections.unmodifiableMap(snapshot);\n    }\n\n    public static void main(String[] args) {\n        // Initialize with some gadget positions\n        Map<String, Position> initialPositions = new HashMap<>();\n        initialPositions.put(\"gadget1\", new Position(10, 20));\n        initialPositions.put(\"gadget2\", new Position(30, 40));\n        initialPositions.put(\"gadget3\", new Position(50, 60));\n\n        DelegatingDeviceTracker tracker = new DelegatingDeviceTracker(initialPositions);\n\n        // Create ExecutorService with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        // Task 1: Continuously update positions\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            Random random = new Random();\n            for (int i = 0; i < 5; i++) {\n                String gadgetId = \"gadget\" + (random.nextInt(3) + 1);\n                Position newPos = new Position(random.nextInt(100), random.nextInt(100));\n                boolean updated = tracker.updatePosition(gadgetId, newPos);\n                System.out.println(\"[\" + threadName + \"] Updating \" + gadgetId + \n                                 \" to \" + newPos + \" - Success: \" + updated);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n\n        // Task 2: Continuously read positions\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String gadgetId = \"gadget\" + ((i % 3) + 1);\n                Position pos = tracker.getPosition(gadgetId);\n                System.out.println(\"[\" + threadName + \"] Reading \" + gadgetId + \n                                 \" position: \" + pos);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n\n        // Main thread operations\n        try {\n            Thread.sleep(200);\n            \n            // Try to update a non-existent gadget\n            boolean failedUpdate = tracker.updatePosition(\"gadget99\", new Position(99, 99));\n            System.out.println(\"[Main Thread] Attempt to update non-existent gadget99: \" + failedUpdate);\n            \n            // Get live view\n            Map<String, Position> liveView = tracker.getLiveUnmodifiableView();\n            System.out.println(\"[Main Thread] Live view size: \" + liveView.size());\n            \n            Thread.sleep(300);\n            \n            // Get static snapshot\n            Map<String, Position> snapshot = tracker.getStaticSnapshot();\n            System.out.println(\"[Main Thread] Snapshot of all positions:\");\n            for (Map.Entry<String, Position> entry : snapshot.entrySet()) {\n                System.out.println(\"  \" + entry.getKey() + \": \" + entry.getValue());\n            }\n            \n            // Demonstrate that snapshot is unmodifiable\n            try {\n                snapshot.put(\"newGadget\", new Position(0, 0));\n            } catch (UnsupportedOperationException e) {\n                System.out.println(\"[Main Thread] Snapshot is unmodifiable - caught expected exception\");\n            }\n            \n            // Demonstrate that live view is unmodifiable\n            try {\n                liveView.put(\"newGadget\", new Position(0, 0));\n            } catch (UnsupportedOperationException e) {\n                System.out.println(\"[Main Thread] Live view is unmodifiable - caught expected exception\");\n            }\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(2, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"\\n[Main Thread] Final positions:\");\n        Map<String, Position> finalSnapshot = tracker.getStaticSnapshot();\n        for (Map.Entry<String, Position> entry : finalSnapshot.entrySet()) {\n            System.out.println(\"  \" + entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass Position {\n    private final int x;\n    private final int y;\n\n    public Position(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public Position(Position position) {\n        this.x = position.x;\n        this.y = position.y;\n    }\n\n    public int getX() {\n        return x;\n    }\n\n    public int getY() {\n        return y;\n    }\n\n    @Override\n    public String toString() {\n        return \"Position{x=\" + x + \", y=\" + y + \"}\";\n    }\n\n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Position position = (Position) o;\n        return x == position.x && y == position.y;\n    }\n\n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n```\n\nThis implementation includes:\n\n1. **DelegatingDeviceTracker class**: Uses `ConcurrentHashMap` for thread-safe operations without explicit synchronization.\n\n2. **Position class**: An immutable class representing gadget positions with defensive copying in the copy constructor.\n\n3. **Thread safety features**:\n   - Uses `ConcurrentHashMap` for concurrent access\n   - Returns defensive copies of Position objects\n   - Provides both live unmodifiable view and static snapshot methods\n   - Updates only succeed for existing gadget IDs\n\n4. **Main method demonstration**:\n   - Uses `ExecutorService` with fixed thread pool of 2 threads\n   - Total of 3 threads including main thread\n   - One thread continuously updates positions\n   - Another thread continuously reads positions\n   - Main thread performs various operations and demonstrates unmodifiable nature of returned maps\n\n5. **Key methods**:\n   - `getPosition()`: Returns a defensive copy of the position\n   - `updatePosition()`: Only updates if gadget exists\n   - `getLiveUnmodifiableView()`: Returns unmodifiable view backed by original data\n   - `getStaticSnapshot()`: Returns unmodifiable snapshot with defensive copies\n\nThe program demonstrates concurrent read/write operations while maintaining thread safety through delegation to `ConcurrentHashMap` rather than explicit synchronization.",
            "Here's a complete Java 8 implementation that meets all your requirements:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingDeviceTracker {\n    private final ConcurrentHashMap<String, Position> locations;\n    private final Map<String, Position> unmodifiableMap;\n    \n    public DelegatingDeviceTracker(Map<String, Position> initialPositions) {\n        this.locations = new ConcurrentHashMap<>(initialPositions);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n    \n    // Get position of a specific gadget\n    public Position getPosition(String gadgetId) {\n        Position pos = locations.get(gadgetId);\n        return pos == null ? null : new Position(pos.getX(), pos.getY());\n    }\n    \n    // Update position of a gadget (only if it exists)\n    public boolean updatePosition(String gadgetId, int x, int y) {\n        Position newPos = new Position(x, y);\n        return locations.replace(gadgetId, locations.get(gadgetId), newPos);\n    }\n    \n    // Returns a live unmodifiable view backed by the original data\n    public Map<String, Position> getLivePositions() {\n        return unmodifiableMap;\n    }\n    \n    // Returns a static snapshot of the current state as an unmodifiable map\n    public Map<String, Position> getSnapshotPositions() {\n        Map<String, Position> snapshot = new HashMap<>();\n        for (Map.Entry<String, Position> entry : locations.entrySet()) {\n            Position pos = entry.getValue();\n            snapshot.put(entry.getKey(), new Position(pos.getX(), pos.getY()));\n        }\n        return Collections.unmodifiableMap(snapshot);\n    }\n    \n    public static void main(String[] args) {\n        // Initialize with some gadgets\n        Map<String, Position> initialPositions = new HashMap<>();\n        initialPositions.put(\"gadget1\", new Position(10, 20));\n        initialPositions.put(\"gadget2\", new Position(30, 40));\n        initialPositions.put(\"gadget3\", new Position(50, 60));\n        \n        DelegatingDeviceTracker tracker = new DelegatingDeviceTracker(initialPositions);\n        \n        // Create a fixed thread pool with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Task 1: Update positions\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            System.out.println(threadName + \" - Starting position updates\");\n            \n            for (int i = 0; i < 5; i++) {\n                boolean updated = tracker.updatePosition(\"gadget1\", \n                    10 + i * 5, 20 + i * 5);\n                System.out.println(threadName + \" - Updated gadget1: \" + updated);\n                \n                updated = tracker.updatePosition(\"gadget2\", \n                    30 + i * 3, 40 + i * 3);\n                System.out.println(threadName + \" - Updated gadget2: \" + updated);\n                \n                // Try to update non-existent gadget\n                updated = tracker.updatePosition(\"gadget99\", 100, 100);\n                System.out.println(threadName + \" - Tried to update non-existent gadget99: \" + updated);\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        // Task 2: Read positions\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            System.out.println(threadName + \" - Starting position reads\");\n            \n            for (int i = 0; i < 5; i++) {\n                Position pos1 = tracker.getPosition(\"gadget1\");\n                Position pos2 = tracker.getPosition(\"gadget2\");\n                Position pos3 = tracker.getPosition(\"gadget3\");\n                \n                System.out.println(threadName + \" - Current positions:\");\n                System.out.println(\"  gadget1: \" + pos1);\n                System.out.println(\"  gadget2: \" + pos2);\n                System.out.println(\"  gadget3: \" + pos3);\n                \n                // Get snapshot\n                Map<String, Position> snapshot = tracker.getSnapshotPositions();\n                System.out.println(threadName + \" - Snapshot size: \" + snapshot.size());\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        // Main thread also does some work\n        System.out.println(\"Main thread - Monitoring live positions\");\n        Map<String, Position> liveView = tracker.getLivePositions();\n        \n        for (int i = 0; i < 3; i++) {\n            System.out.println(\"Main thread - Live view size: \" + liveView.size());\n            System.out.println(\"Main thread - Live positions: \" + liveView);\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(2, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        // Final state\n        System.out.println(\"\\nFinal positions:\");\n        Map<String, Position> finalSnapshot = tracker.getSnapshotPositions();\n        for (Map.Entry<String, Position> entry : finalSnapshot.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass Position {\n    private final int x;\n    private final int y;\n    \n    public Position(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public int getX() {\n        return x;\n    }\n    \n    public int getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Position[x=\" + x + \", y=\" + y + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return x == position.x && y == position.y;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n```\n\nThis implementation provides:\n\n1. **Thread Safety**: Uses `ConcurrentHashMap` for thread-safe operations without explicit synchronization\n2. **Delegation Pattern**: The class delegates to `ConcurrentHashMap` for thread-safe operations\n3. **Position Management**: \n   - `getPosition()`: Returns a defensive copy of the position\n   - `updatePosition()`: Only updates if the gadget exists (using `replace()`)\n4. **Two View Methods**:\n   - `getLivePositions()`: Returns an unmodifiable live view backed by the original map\n   - `getSnapshotPositions()`: Returns a static snapshot with defensive copies\n5. **Concurrency**: Uses a fixed thread pool with 2 threads plus the main thread (total of 3)\n6. **Immutable Position Class**: The `Position` class is immutable for thread safety\n\nThe program demonstrates concurrent reads and writes to the tracker, showing that multiple threads can safely access and modify gadget positions simultaneously."
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Returning a static copy of the location set instead of a 'live' one. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called DelegatingParcelTracker that tracks the positions of packages in a thread-safe manner using a ConcurrentHashMap. The class should provide methods to retrieve the position of a specific package, assign the position of a package, and return an unmodifiable view of all package positions. Use delegation to ensure thread safety without explicitly synchronizing methods. Initialize the tracker with a map of package IDs to their initial positions. Include two versions of the method to retrieve all positions: one that returns a live unmodifiable map backed by the original data, and another that returns a static snapshot of the current state as an unmodifiable map. Ensure that assigning a package's position only succeeds if the package ID already exists in the map. The requirements are as follows:\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingParcelTracker {\n    private final ConcurrentHashMap<String, Position> parcelPositions;\n    \n    public DelegatingParcelTracker(Map<String, Position> initialPositions) {\n        this.parcelPositions = new ConcurrentHashMap<>(initialPositions);\n    }\n    \n    // Get position of a specific package\n    public Position getPosition(String parcelId) {\n        return parcelPositions.get(parcelId);\n    }\n    \n    // Assign position only if package ID exists\n    public boolean assignPosition(String parcelId, Position newPosition) {\n        if (newPosition == null) {\n            throw new IllegalArgumentException(\"Position cannot be null\");\n        }\n        // replace() only updates if key exists\n        return parcelPositions.replace(parcelId, newPosition) != null;\n    }\n    \n    // Returns live unmodifiable view backed by original data\n    public Map<String, Position> getAllPositionsLive() {\n        return Collections.unmodifiableMap(parcelPositions);\n    }\n    \n    // Returns static snapshot as unmodifiable map\n    public Map<String, Position> getAllPositionsSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(parcelPositions));\n    }\n    \n    public static void main(String[] args) {\n        // Initialize with some test data\n        Map<String, Position> initialData = new HashMap<>();\n        initialData.put(\"PKG001\", new Position(10.5, 20.3));\n        initialData.put(\"PKG002\", new Position(15.2, 25.8));\n        initialData.put(\"PKG003\", new Position(30.1, 40.7));\n        initialData.put(\"PKG004\", new Position(5.5, 10.2));\n        \n        DelegatingParcelTracker tracker = new DelegatingParcelTracker(initialData);\n        \n        // Create executor with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Task 1: Update positions concurrently\n        Runnable updateTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            Random random = new Random();\n            \n            for (int i = 0; i < 5; i++) {\n                String parcelId = \"PKG00\" + (random.nextInt(4) + 1);\n                double newX = random.nextDouble() * 100;\n                double newY = random.nextDouble() * 100;\n                Position newPos = new Position(newX, newY);\n                \n                boolean updated = tracker.assignPosition(parcelId, newPos);\n                System.out.printf(\"[%s] Updated %s to (%.2f, %.2f): %s%n\", \n                    threadName, parcelId, newX, newY, updated);\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Task 2: Read positions concurrently\n        Runnable readTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            \n            for (int i = 0; i < 3; i++) {\n                // Test live view\n                Map<String, Position> liveView = tracker.getAllPositionsLive();\n                System.out.printf(\"[%s] Live view size: %d%n\", threadName, liveView.size());\n                \n                // Test snapshot\n                Map<String, Position> snapshot = tracker.getAllPositionsSnapshot();\n                System.out.printf(\"[%s] Snapshot contents:%n\", threadName);\n                snapshot.forEach((id, pos) -> \n                    System.out.printf(\"  %s: %s%n\", id, pos));\n                \n                // Test individual retrieval\n                Position pos = tracker.getPosition(\"PKG001\");\n                if (pos != null) {\n                    System.out.printf(\"[%s] PKG001 position: %s%n\", threadName, pos);\n                }\n                \n                try {\n                    Thread.sleep(200);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> updateFuture = executor.submit(updateTask);\n        Future<?> readFuture = executor.submit(readTask);\n        \n        // Main thread also performs some operations\n        System.out.println(\"[Main Thread] Starting concurrent operations...\");\n        \n        // Test assigning to non-existent package\n        boolean failedUpdate = tracker.assignPosition(\"PKG999\", new Position(0, 0));\n        System.out.printf(\"[Main Thread] Attempt to update non-existent PKG999: %s%n\", failedUpdate);\n        \n        // Main thread reads while other threads are working\n        try {\n            Thread.sleep(300);\n            Map<String, Position> mainSnapshot = tracker.getAllPositionsSnapshot();\n            System.out.printf(\"[Main Thread] Current packages in system: %d%n\", mainSnapshot.size());\n            \n            // Wait for tasks to complete\n            updateFuture.get(2, TimeUnit.SECONDS);\n            readFuture.get(2, TimeUnit.SECONDS);\n            \n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error during execution: \" + e.getMessage());\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        // Final state\n        System.out.println(\"\\n[Main Thread] Final state of all packages:\");\n        Map<String, Position> finalState = tracker.getAllPositionsSnapshot();\n        finalState.forEach((id, pos) -> \n            System.out.printf(\"  %s: %s%n\", id, pos));\n        \n        // Demonstrate that live view reflects changes\n        System.out.println(\"\\n[Main Thread] Testing live view behavior:\");\n        Map<String, Position> liveView = tracker.getAllPositionsLive();\n        System.out.println(\"Live view size before update: \" + liveView.size());\n        tracker.assignPosition(\"PKG001\", new Position(999.9, 888.8));\n        System.out.println(\"Live view size after update: \" + liveView.size());\n        System.out.println(\"PKG001 in live view: \" + liveView.get(\"PKG001\"));\n        \n        // Try to modify the unmodifiable views (will throw exception if attempted)\n        try {\n            liveView.put(\"PKG005\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Successfully prevented modification of unmodifiable view\");\n        }\n    }\n}\n\nclass Position {\n    private final double x;\n    private final double y;\n    \n    public Position(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public double getX() {\n        return x;\n    }\n    \n    public double getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"Position(%.2f, %.2f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return Double.compare(position.x, x) == 0 && \n               Double.compare(position.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Position {\n    private final double latitude;\n    private final double longitude;\n    \n    public Position(double latitude, double longitude) {\n        this.latitude = latitude;\n        this.longitude = longitude;\n    }\n    \n    public double getLatitude() {\n        return latitude;\n    }\n    \n    public double getLongitude() {\n        return longitude;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"Position[lat=%.2f, lon=%.2f]\", latitude, longitude);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return Double.compare(position.latitude, latitude) == 0 &&\n               Double.compare(position.longitude, longitude) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(latitude, longitude);\n    }\n}\n\nclass DelegatingParcelTracker {\n    private final ConcurrentHashMap<String, Position> packagePositions;\n    \n    public DelegatingParcelTracker(Map<String, Position> initialPositions) {\n        this.packagePositions = new ConcurrentHashMap<>(initialPositions);\n    }\n    \n    public Position getPosition(String packageId) {\n        return packagePositions.get(packageId);\n    }\n    \n    public boolean assignPosition(String packageId, Position position) {\n        if (position == null) {\n            throw new IllegalArgumentException(\"Position cannot be null\");\n        }\n        \n        // Only update if the key already exists\n        Position oldPosition = packagePositions.replace(packageId, position);\n        return oldPosition != null;\n    }\n    \n    public Map<String, Position> getAllPositionsLive() {\n        return Collections.unmodifiableMap(packagePositions);\n    }\n    \n    public Map<String, Position> getAllPositionsSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(packagePositions));\n    }\n    \n    public boolean containsPackage(String packageId) {\n        return packagePositions.containsKey(packageId);\n    }\n    \n    public int getPackageCount() {\n        return packagePositions.size();\n    }\n}\n\npublic class ParcelTrackingSystem {\n    \n    static class PositionUpdater implements Runnable {\n        private final DelegatingParcelTracker tracker;\n        private final String threadName;\n        private final Random random;\n        \n        public PositionUpdater(DelegatingParcelTracker tracker, String threadName) {\n            this.tracker = tracker;\n            this.threadName = threadName;\n            this.random = new Random();\n        }\n        \n        @Override\n        public void run() {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    String packageId = \"PKG-\" + (random.nextInt(5) + 1);\n                    double newLat = 40.0 + random.nextDouble() * 10;\n                    double newLon = -74.0 + random.nextDouble() * 10;\n                    Position newPosition = new Position(newLat, newLon);\n                    \n                    boolean updated = tracker.assignPosition(packageId, newPosition);\n                    \n                    System.out.println(String.format(\"[%s] %s position for %s to %s\",\n                        threadName,\n                        updated ? \"Updated\" : \"Failed to update\",\n                        packageId,\n                        newPosition));\n                    \n                    Thread.sleep(random.nextInt(500) + 100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                System.out.println(threadName + \" was interrupted\");\n            }\n        }\n    }\n    \n    static class PositionReader implements Runnable {\n        private final DelegatingParcelTracker tracker;\n        private final String threadName;\n        private final Random random;\n        \n        public PositionReader(DelegatingParcelTracker tracker, String threadName) {\n            this.tracker = tracker;\n            this.threadName = threadName;\n            this.random = new Random();\n        }\n        \n        @Override\n        public void run() {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    String packageId = \"PKG-\" + (random.nextInt(5) + 1);\n                    Position position = tracker.getPosition(packageId);\n                    \n                    if (position != null) {\n                        System.out.println(String.format(\"[%s] Read position for %s: %s\",\n                            threadName, packageId, position));\n                    } else {\n                        System.out.println(String.format(\"[%s] No position found for %s\",\n                            threadName, packageId));\n                    }\n                    \n                    if (i == 2) {\n                        Map<String, Position> snapshot = tracker.getAllPositionsSnapshot();\n                        System.out.println(String.format(\"[%s] Snapshot contains %d packages\",\n                            threadName, snapshot.size()));\n                    }\n                    \n                    Thread.sleep(random.nextInt(500) + 100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                System.out.println(threadName + \" was interrupted\");\n            }\n        }\n    }\n    \n    public static void main(String[] args) {\n        // Initialize tracker with some packages\n        Map<String, Position> initialPositions = new HashMap<>();\n        initialPositions.put(\"PKG-1\", new Position(40.7128, -74.0060));\n        initialPositions.put(\"PKG-2\", new Position(34.0522, -118.2437));\n        initialPositions.put(\"PKG-3\", new Position(41.8781, -87.6298));\n        initialPositions.put(\"PKG-4\", new Position(37.7749, -122.4194));\n        initialPositions.put(\"PKG-5\", new Position(42.3601, -71.0589));\n        \n        DelegatingParcelTracker tracker = new DelegatingParcelTracker(initialPositions);\n        \n        System.out.println(\"Initial package count: \" + tracker.getPackageCount());\n        System.out.println(\"\\nStarting concurrent operations...\\n\");\n        \n        // Create a fixed thread pool with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Submit tasks\n        executor.submit(new PositionUpdater(tracker, \"Updater-1\"));\n        executor.submit(new PositionReader(tracker, \"Reader-1\"));\n        \n        // Main thread also performs some operations\n        try {\n            Thread.sleep(1000);\n            \n            System.out.println(\"\\n[Main Thread] Getting live view of all positions:\");\n            Map<String, Position> liveView = tracker.getAllPositionsLive();\n            for (Map.Entry<String, Position> entry : liveView.entrySet()) {\n                System.out.println(\"  \" + entry.getKey() + \" -> \" + entry.getValue());\n            }\n            \n            // Try to update a non-existent package\n            boolean result = tracker.assignPosition(\"PKG-999\", new Position(0, 0));\n            System.out.println(\"\\n[Main Thread] Attempt to update non-existent PKG-999: \" + \n                              (result ? \"Success\" : \"Failed\"));\n            \n            // Update an existing package\n            result = tracker.assignPosition(\"PKG-1\", new Position(50.0, -80.0));\n            System.out.println(\"[Main Thread] Update existing PKG-1: \" + \n                              (result ? \"Success\" : \"Failed\"));\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"\\n\\nFinal state:\");\n        System.out.println(\"Package count: \" + tracker.getPackageCount());\n        Map<String, Position> finalSnapshot = tracker.getAllPositionsSnapshot();\n        for (Map.Entry<String, Position> entry : finalSnapshot.entrySet()) {\n            System.out.println(\"  \" + entry.getKey() + \" -> \" + entry.getValue());\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingParcelTracker {\n    private final ConcurrentHashMap<String, Position> parcelPositions;\n    \n    public DelegatingParcelTracker(Map<String, Position> initialPositions) {\n        this.parcelPositions = new ConcurrentHashMap<>(initialPositions);\n    }\n    \n    public Position getPosition(String packageId) {\n        return parcelPositions.get(packageId);\n    }\n    \n    public boolean assignPosition(String packageId, Position newPosition) {\n        if (packageId == null || newPosition == null) {\n            return false;\n        }\n        return parcelPositions.replace(packageId, parcelPositions.get(packageId), newPosition);\n    }\n    \n    public Map<String, Position> getLiveUnmodifiableView() {\n        return Collections.unmodifiableMap(parcelPositions);\n    }\n    \n    public Map<String, Position> getStaticSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(parcelPositions));\n    }\n    \n    public static void main(String[] args) {\n        // Initialize with some test data\n        Map<String, Position> initialData = new HashMap<>();\n        initialData.put(\"PKG001\", new Position(10.0, 20.0));\n        initialData.put(\"PKG002\", new Position(30.0, 40.0));\n        initialData.put(\"PKG003\", new Position(50.0, 60.0));\n        initialData.put(\"PKG004\", new Position(70.0, 80.0));\n        \n        DelegatingParcelTracker tracker = new DelegatingParcelTracker(initialData);\n        \n        // Create a fixed thread pool with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Create concurrent tasks\n        Runnable updateTask1 = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String packageId = \"PKG001\";\n                Position oldPos = tracker.getPosition(packageId);\n                if (oldPos != null) {\n                    Position newPos = new Position(oldPos.x + i * 10, oldPos.y + i * 10);\n                    boolean success = tracker.assignPosition(packageId, newPos);\n                    System.out.println(threadName + \" - Updated \" + packageId + \n                                     \" to \" + newPos + \": \" + success);\n                }\n                \n                packageId = \"PKG002\";\n                oldPos = tracker.getPosition(packageId);\n                if (oldPos != null) {\n                    Position newPos = new Position(oldPos.x - i * 5, oldPos.y - i * 5);\n                    boolean success = tracker.assignPosition(packageId, newPos);\n                    System.out.println(threadName + \" - Updated \" + packageId + \n                                     \" to \" + newPos + \": \" + success);\n                }\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        Runnable updateTask2 = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String packageId = \"PKG003\";\n                Position oldPos = tracker.getPosition(packageId);\n                if (oldPos != null) {\n                    Position newPos = new Position(oldPos.x + i * 15, oldPos.y - i * 15);\n                    boolean success = tracker.assignPosition(packageId, newPos);\n                    System.out.println(threadName + \" - Updated \" + packageId + \n                                     \" to \" + newPos + \": \" + success);\n                }\n                \n                // Try to update a non-existent package\n                boolean failedUpdate = tracker.assignPosition(\"PKG999\", new Position(100, 100));\n                System.out.println(threadName + \" - Attempted to update non-existent PKG999: \" + failedUpdate);\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> future1 = executor.submit(updateTask1);\n        Future<?> future2 = executor.submit(updateTask2);\n        \n        // Main thread also performs some operations\n        System.out.println(\"\\nMain thread operations:\");\n        for (int i = 0; i < 3; i++) {\n            // Get snapshot and live view\n            Map<String, Position> snapshot = tracker.getStaticSnapshot();\n            Map<String, Position> liveView = tracker.getLiveUnmodifiableView();\n            \n            System.out.println(\"\\n--- Iteration \" + i + \" ---\");\n            System.out.println(\"Snapshot size: \" + snapshot.size());\n            System.out.println(\"Live view size: \" + liveView.size());\n            \n            // Update PKG004\n            Position pkg4Pos = tracker.getPosition(\"PKG004\");\n            if (pkg4Pos != null) {\n                Position newPos = new Position(pkg4Pos.x + i * 20, pkg4Pos.y + i * 20);\n                boolean success = tracker.assignPosition(\"PKG004\", newPos);\n                System.out.println(\"Main thread - Updated PKG004 to \" + newPos + \": \" + success);\n            }\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                break;\n            }\n        }\n        \n        // Wait for tasks to complete\n        try {\n            future1.get(3, TimeUnit.SECONDS);\n            future2.get(3, TimeUnit.SECONDS);\n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error waiting for tasks: \" + e.getMessage());\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        // Print final state\n        System.out.println(\"\\n=== Final Package Positions ===\");\n        Map<String, Position> finalSnapshot = tracker.getStaticSnapshot();\n        finalSnapshot.forEach((id, pos) -> \n            System.out.println(id + \": \" + pos));\n        \n        // Demonstrate that live view reflects changes\n        System.out.println(\"\\n=== Testing Live View vs Snapshot ===\");\n        Map<String, Position> liveView = tracker.getLiveUnmodifiableView();\n        Map<String, Position> staticSnapshot = tracker.getStaticSnapshot();\n        \n        System.out.println(\"Before update - PKG001 in live view: \" + liveView.get(\"PKG001\"));\n        System.out.println(\"Before update - PKG001 in snapshot: \" + staticSnapshot.get(\"PKG001\"));\n        \n        tracker.assignPosition(\"PKG001\", new Position(999, 999));\n        \n        System.out.println(\"After update - PKG001 in live view: \" + liveView.get(\"PKG001\"));\n        System.out.println(\"After update - PKG001 in snapshot: \" + staticSnapshot.get(\"PKG001\"));\n        \n        // Try to modify unmodifiable maps (will throw exception)\n        try {\n            liveView.put(\"PKG001\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"\\nCorrectly prevented modification of live view\");\n        }\n        \n        try {\n            staticSnapshot.put(\"PKG001\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Correctly prevented modification of snapshot\");\n        }\n    }\n}\n\nclass Position {\n    final double x;\n    final double y;\n    \n    public Position(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"Position(%.1f, %.1f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return Double.compare(position.x, x) == 0 && \n               Double.compare(position.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.awt.Point;\nimport java.util.*;\nimport java.util.concurrent.*;\n\n/**\n* DelegatingVehicleTracker\n* Delegates thread safety to a ConcurrentHashMap.\n*/\npublic class DelegatingVehicleTracker {\n\nprivate final ConcurrentMap<String, Point> locations;\nprivate final Map<String, Point> unmodifiableMap;\n\npublic DelegatingVehicleTracker(Map<String, Point> points) {\nlocations = new ConcurrentHashMap<>(points);\nunmodifiableMap = Collections.unmodifiableMap(locations);\n}\n\npublic Map<String, Point> getLocations() {\nreturn unmodifiableMap;\n}\n\n\npublic void setLocation(String id, int x, int y) {\nif (locations.replace(id, new Point(x, y)) == null)\nthrow new IllegalArgumentException(\"Invalid vehicle name: \" + id);\n}\n\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, Point> initialVehicles = new HashMap<>();\ninitialVehicles.put(\"V1\", new Point(0, 0));\ninitialVehicles.put(\"V2\", new Point(0, 0));\ninitialVehicles.put(\"V3\", new Point(0, 0));\n\nDelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialVehicles);\n\n// Reduce threads to 2 for JPF-friendly execution\nThread[] threads = new Thread[2];\n\nfor (int i = 0; i < 2; i++) {\nfinal String vehicleId = \"V\" + ((i % 3) + 1);\nthreads[i] = new Thread(() -> {\ntry {\n// Reduce iterations to 2 per thread\nfor (int j = 0; j < 2; j++) {\n// Use deterministic fixed values instead of random\nint x = j * 10 + 5;\nint y = j * 20 + 5;\ntracker.setLocation(vehicleId, x, y);\nSystem.out.println(Thread.currentThread().getName() +\n\" updated \" + vehicleId + \" to (\" + x + \", \" + y + \")\");\nThread.sleep(10);\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\ntracker.getLocations().forEach((id, point) ->\nSystem.out.println(id + \": (\" + point.x + \", \" + point.y + \")\"));\n}\n}",
        "max_depth": "57",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 57.32%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.48%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=100090,visited=108428,backtracked=207950,end=0\nsearch:             maxDepth=570,constraints=59054\nchoice generators:  thread=69878 (signal=0,lock=24,sharedRef=66601,threadApi=63,reschedule=0), data=0\nheap:               new=543813,released=204166,maxLive=1138,gcCycles=201312\ninstructions:       17328481\nmax memory:         1018MB\nloaded code:        classes=160,methods=2687\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.12%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.46%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=116842,visited=93235,backtracked=209517,end=1\nsearch:             maxDepth=570,constraints=54849\nchoice generators:  thread=70393 (signal=0,lock=239,sharedRef=57324,threadApi=2456,reschedule=14), data=0\nheap:               new=318992,released=147736,maxLive=1158,gcCycles=195375\ninstructions:       50809458\nmax memory:         1018MB\nloaded code:        classes=162,methods=2757\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 52.44%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.52%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.51%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=132226,visited=129519,backtracked=261177,end=0\nsearch:             maxDepth=570,constraints=79690\nchoice generators:  thread=87628 (signal=0,lock=78,sharedRef=81590,threadApi=65,reschedule=0), data=0\nheap:               new=540788,released=106919,maxLive=891,gcCycles=253440\ninstructions:       20227450\nmax memory:         1020MB\nloaded code:        classes=159,methods=2672\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            54.13,
            58.49,
            55.54
        ],
        "llm_output": [
            "Here's a complete Java 8 program that implements the DelegatingParcelTracker with all the specified requirements:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingParcelTracker {\n    private final ConcurrentHashMap<String, Position> parcelPositions;\n    \n    public DelegatingParcelTracker(Map<String, Position> initialPositions) {\n        this.parcelPositions = new ConcurrentHashMap<>(initialPositions);\n    }\n    \n    // Get position of a specific package\n    public Position getPosition(String parcelId) {\n        return parcelPositions.get(parcelId);\n    }\n    \n    // Assign position only if package ID exists\n    public boolean assignPosition(String parcelId, Position newPosition) {\n        if (newPosition == null) {\n            throw new IllegalArgumentException(\"Position cannot be null\");\n        }\n        // replace() only updates if key exists\n        return parcelPositions.replace(parcelId, newPosition) != null;\n    }\n    \n    // Returns live unmodifiable view backed by original data\n    public Map<String, Position> getAllPositionsLive() {\n        return Collections.unmodifiableMap(parcelPositions);\n    }\n    \n    // Returns static snapshot as unmodifiable map\n    public Map<String, Position> getAllPositionsSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(parcelPositions));\n    }\n    \n    public static void main(String[] args) {\n        // Initialize with some test data\n        Map<String, Position> initialData = new HashMap<>();\n        initialData.put(\"PKG001\", new Position(10.5, 20.3));\n        initialData.put(\"PKG002\", new Position(15.2, 25.8));\n        initialData.put(\"PKG003\", new Position(30.1, 40.7));\n        initialData.put(\"PKG004\", new Position(5.5, 10.2));\n        \n        DelegatingParcelTracker tracker = new DelegatingParcelTracker(initialData);\n        \n        // Create executor with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Task 1: Update positions concurrently\n        Runnable updateTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            Random random = new Random();\n            \n            for (int i = 0; i < 5; i++) {\n                String parcelId = \"PKG00\" + (random.nextInt(4) + 1);\n                double newX = random.nextDouble() * 100;\n                double newY = random.nextDouble() * 100;\n                Position newPos = new Position(newX, newY);\n                \n                boolean updated = tracker.assignPosition(parcelId, newPos);\n                System.out.printf(\"[%s] Updated %s to (%.2f, %.2f): %s%n\", \n                    threadName, parcelId, newX, newY, updated);\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Task 2: Read positions concurrently\n        Runnable readTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            \n            for (int i = 0; i < 3; i++) {\n                // Test live view\n                Map<String, Position> liveView = tracker.getAllPositionsLive();\n                System.out.printf(\"[%s] Live view size: %d%n\", threadName, liveView.size());\n                \n                // Test snapshot\n                Map<String, Position> snapshot = tracker.getAllPositionsSnapshot();\n                System.out.printf(\"[%s] Snapshot contents:%n\", threadName);\n                snapshot.forEach((id, pos) -> \n                    System.out.printf(\"  %s: %s%n\", id, pos));\n                \n                // Test individual retrieval\n                Position pos = tracker.getPosition(\"PKG001\");\n                if (pos != null) {\n                    System.out.printf(\"[%s] PKG001 position: %s%n\", threadName, pos);\n                }\n                \n                try {\n                    Thread.sleep(200);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> updateFuture = executor.submit(updateTask);\n        Future<?> readFuture = executor.submit(readTask);\n        \n        // Main thread also performs some operations\n        System.out.println(\"[Main Thread] Starting concurrent operations...\");\n        \n        // Test assigning to non-existent package\n        boolean failedUpdate = tracker.assignPosition(\"PKG999\", new Position(0, 0));\n        System.out.printf(\"[Main Thread] Attempt to update non-existent PKG999: %s%n\", failedUpdate);\n        \n        // Main thread reads while other threads are working\n        try {\n            Thread.sleep(300);\n            Map<String, Position> mainSnapshot = tracker.getAllPositionsSnapshot();\n            System.out.printf(\"[Main Thread] Current packages in system: %d%n\", mainSnapshot.size());\n            \n            // Wait for tasks to complete\n            updateFuture.get(2, TimeUnit.SECONDS);\n            readFuture.get(2, TimeUnit.SECONDS);\n            \n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error during execution: \" + e.getMessage());\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        // Final state\n        System.out.println(\"\\n[Main Thread] Final state of all packages:\");\n        Map<String, Position> finalState = tracker.getAllPositionsSnapshot();\n        finalState.forEach((id, pos) -> \n            System.out.printf(\"  %s: %s%n\", id, pos));\n        \n        // Demonstrate that live view reflects changes\n        System.out.println(\"\\n[Main Thread] Testing live view behavior:\");\n        Map<String, Position> liveView = tracker.getAllPositionsLive();\n        System.out.println(\"Live view size before update: \" + liveView.size());\n        tracker.assignPosition(\"PKG001\", new Position(999.9, 888.8));\n        System.out.println(\"Live view size after update: \" + liveView.size());\n        System.out.println(\"PKG001 in live view: \" + liveView.get(\"PKG001\"));\n        \n        // Try to modify the unmodifiable views (will throw exception if attempted)\n        try {\n            liveView.put(\"PKG005\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Successfully prevented modification of unmodifiable view\");\n        }\n    }\n}\n\nclass Position {\n    private final double x;\n    private final double y;\n    \n    public Position(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public double getX() {\n        return x;\n    }\n    \n    public double getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"Position(%.2f, %.2f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return Double.compare(position.x, x) == 0 && \n               Double.compare(position.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n```\n\nThis implementation provides:\n\n1. **Thread-safe delegation**: The `DelegatingParcelTracker` class delegates all thread-safety concerns to `ConcurrentHashMap`, avoiding explicit synchronization.\n\n2. **Required methods**:\n   - `getPosition()`: Retrieves a specific package's position\n   - `assignPosition()`: Updates position only if package ID exists (using `replace()`)\n   - `getAllPositionsLive()`: Returns an unmodifiable live view\n   - `getAllPositionsSnapshot()`: Returns an unmodifiable static snapshot\n\n3. **Concurrency demonstration**: \n   - Uses a fixed thread pool with 2 threads (plus main thread = 3 total)\n   - One thread updates positions\n   - One thread reads positions\n   - Main thread also performs operations\n\n4. **Thread safety**: \n   - ConcurrentHashMap handles all concurrent access\n   - Position class is immutable for thread safety\n   - No explicit synchronization needed due to delegation\n\n5. **Unmodifiable views**: Both `getAllPositionsLive()` and `getAllPositionsSnapshot()` return unmodifiable maps to prevent external modification.\n\nThe program demonstrates concurrent reading and writing operations while maintaining thread safety through delegation to ConcurrentHashMap's built-in thread-safe operations.",
            "Here's a complete Java 8 program that implements the DelegatingParcelTracker with thread-safe operations:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Position {\n    private final double latitude;\n    private final double longitude;\n    \n    public Position(double latitude, double longitude) {\n        this.latitude = latitude;\n        this.longitude = longitude;\n    }\n    \n    public double getLatitude() {\n        return latitude;\n    }\n    \n    public double getLongitude() {\n        return longitude;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"Position[lat=%.2f, lon=%.2f]\", latitude, longitude);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return Double.compare(position.latitude, latitude) == 0 &&\n               Double.compare(position.longitude, longitude) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(latitude, longitude);\n    }\n}\n\nclass DelegatingParcelTracker {\n    private final ConcurrentHashMap<String, Position> packagePositions;\n    \n    public DelegatingParcelTracker(Map<String, Position> initialPositions) {\n        this.packagePositions = new ConcurrentHashMap<>(initialPositions);\n    }\n    \n    public Position getPosition(String packageId) {\n        return packagePositions.get(packageId);\n    }\n    \n    public boolean assignPosition(String packageId, Position position) {\n        if (position == null) {\n            throw new IllegalArgumentException(\"Position cannot be null\");\n        }\n        \n        // Only update if the key already exists\n        Position oldPosition = packagePositions.replace(packageId, position);\n        return oldPosition != null;\n    }\n    \n    public Map<String, Position> getAllPositionsLive() {\n        return Collections.unmodifiableMap(packagePositions);\n    }\n    \n    public Map<String, Position> getAllPositionsSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(packagePositions));\n    }\n    \n    public boolean containsPackage(String packageId) {\n        return packagePositions.containsKey(packageId);\n    }\n    \n    public int getPackageCount() {\n        return packagePositions.size();\n    }\n}\n\npublic class ParcelTrackingSystem {\n    \n    static class PositionUpdater implements Runnable {\n        private final DelegatingParcelTracker tracker;\n        private final String threadName;\n        private final Random random;\n        \n        public PositionUpdater(DelegatingParcelTracker tracker, String threadName) {\n            this.tracker = tracker;\n            this.threadName = threadName;\n            this.random = new Random();\n        }\n        \n        @Override\n        public void run() {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    String packageId = \"PKG-\" + (random.nextInt(5) + 1);\n                    double newLat = 40.0 + random.nextDouble() * 10;\n                    double newLon = -74.0 + random.nextDouble() * 10;\n                    Position newPosition = new Position(newLat, newLon);\n                    \n                    boolean updated = tracker.assignPosition(packageId, newPosition);\n                    \n                    System.out.println(String.format(\"[%s] %s position for %s to %s\",\n                        threadName,\n                        updated ? \"Updated\" : \"Failed to update\",\n                        packageId,\n                        newPosition));\n                    \n                    Thread.sleep(random.nextInt(500) + 100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                System.out.println(threadName + \" was interrupted\");\n            }\n        }\n    }\n    \n    static class PositionReader implements Runnable {\n        private final DelegatingParcelTracker tracker;\n        private final String threadName;\n        private final Random random;\n        \n        public PositionReader(DelegatingParcelTracker tracker, String threadName) {\n            this.tracker = tracker;\n            this.threadName = threadName;\n            this.random = new Random();\n        }\n        \n        @Override\n        public void run() {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    String packageId = \"PKG-\" + (random.nextInt(5) + 1);\n                    Position position = tracker.getPosition(packageId);\n                    \n                    if (position != null) {\n                        System.out.println(String.format(\"[%s] Read position for %s: %s\",\n                            threadName, packageId, position));\n                    } else {\n                        System.out.println(String.format(\"[%s] No position found for %s\",\n                            threadName, packageId));\n                    }\n                    \n                    if (i == 2) {\n                        Map<String, Position> snapshot = tracker.getAllPositionsSnapshot();\n                        System.out.println(String.format(\"[%s] Snapshot contains %d packages\",\n                            threadName, snapshot.size()));\n                    }\n                    \n                    Thread.sleep(random.nextInt(500) + 100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                System.out.println(threadName + \" was interrupted\");\n            }\n        }\n    }\n    \n    public static void main(String[] args) {\n        // Initialize tracker with some packages\n        Map<String, Position> initialPositions = new HashMap<>();\n        initialPositions.put(\"PKG-1\", new Position(40.7128, -74.0060));\n        initialPositions.put(\"PKG-2\", new Position(34.0522, -118.2437));\n        initialPositions.put(\"PKG-3\", new Position(41.8781, -87.6298));\n        initialPositions.put(\"PKG-4\", new Position(37.7749, -122.4194));\n        initialPositions.put(\"PKG-5\", new Position(42.3601, -71.0589));\n        \n        DelegatingParcelTracker tracker = new DelegatingParcelTracker(initialPositions);\n        \n        System.out.println(\"Initial package count: \" + tracker.getPackageCount());\n        System.out.println(\"\\nStarting concurrent operations...\\n\");\n        \n        // Create a fixed thread pool with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Submit tasks\n        executor.submit(new PositionUpdater(tracker, \"Updater-1\"));\n        executor.submit(new PositionReader(tracker, \"Reader-1\"));\n        \n        // Main thread also performs some operations\n        try {\n            Thread.sleep(1000);\n            \n            System.out.println(\"\\n[Main Thread] Getting live view of all positions:\");\n            Map<String, Position> liveView = tracker.getAllPositionsLive();\n            for (Map.Entry<String, Position> entry : liveView.entrySet()) {\n                System.out.println(\"  \" + entry.getKey() + \" -> \" + entry.getValue());\n            }\n            \n            // Try to update a non-existent package\n            boolean result = tracker.assignPosition(\"PKG-999\", new Position(0, 0));\n            System.out.println(\"\\n[Main Thread] Attempt to update non-existent PKG-999: \" + \n                              (result ? \"Success\" : \"Failed\"));\n            \n            // Update an existing package\n            result = tracker.assignPosition(\"PKG-1\", new Position(50.0, -80.0));\n            System.out.println(\"[Main Thread] Update existing PKG-1: \" + \n                              (result ? \"Success\" : \"Failed\"));\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"\\n\\nFinal state:\");\n        System.out.println(\"Package count: \" + tracker.getPackageCount());\n        Map<String, Position> finalSnapshot = tracker.getAllPositionsSnapshot();\n        for (Map.Entry<String, Position> entry : finalSnapshot.entrySet()) {\n            System.out.println(\"  \" + entry.getKey() + \" -> \" + entry.getValue());\n        }\n    }\n}\n```\n\nThis implementation includes:\n\n1. **Position class**: A simple immutable class to represent package positions with latitude and longitude.\n\n2. **DelegatingParcelTracker class**: The main tracker class that:\n   - Uses `ConcurrentHashMap` for thread-safe operations\n   - Delegates thread safety to the concurrent collection\n   - Provides `getPosition()` to retrieve a single package position\n   - Provides `assignPosition()` that only updates existing packages\n   - Provides `getAllPositionsLive()` for a live unmodifiable view\n   - Provides `getAllPositionsSnapshot()` for a static snapshot\n\n3. **Thread-safe operations**: \n   - No explicit synchronization needed due to delegation to `ConcurrentHashMap`\n   - The `replace()` method ensures atomic update only if key exists\n   - Unmodifiable views prevent external modification\n\n4. **Concurrent testing**: \n   - Uses `ExecutorService` with fixed thread pool of 2 threads\n   - Total of 3 threads including main thread\n   - Demonstrates concurrent reads and writes\n   - Shows both live view and snapshot functionality\n\n5. **Key features**:\n   - Thread-safe without explicit synchronization\n   - Follows Java 8 syntax and conventions\n   - All code in a single file\n   - Clear demonstration of concurrent operations\n   - Proper thread management and shutdown\n\nThe program demonstrates concurrent access patterns where multiple threads can safely read and update package positions simultaneously, while maintaining data consistency through the delegating pattern using `ConcurrentHashMap`.",
            "Here's a complete Java 8 implementation that meets all your requirements:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingParcelTracker {\n    private final ConcurrentHashMap<String, Position> parcelPositions;\n    \n    public DelegatingParcelTracker(Map<String, Position> initialPositions) {\n        this.parcelPositions = new ConcurrentHashMap<>(initialPositions);\n    }\n    \n    public Position getPosition(String packageId) {\n        return parcelPositions.get(packageId);\n    }\n    \n    public boolean assignPosition(String packageId, Position newPosition) {\n        if (packageId == null || newPosition == null) {\n            return false;\n        }\n        return parcelPositions.replace(packageId, parcelPositions.get(packageId), newPosition);\n    }\n    \n    public Map<String, Position> getLiveUnmodifiableView() {\n        return Collections.unmodifiableMap(parcelPositions);\n    }\n    \n    public Map<String, Position> getStaticSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(parcelPositions));\n    }\n    \n    public static void main(String[] args) {\n        // Initialize with some test data\n        Map<String, Position> initialData = new HashMap<>();\n        initialData.put(\"PKG001\", new Position(10.0, 20.0));\n        initialData.put(\"PKG002\", new Position(30.0, 40.0));\n        initialData.put(\"PKG003\", new Position(50.0, 60.0));\n        initialData.put(\"PKG004\", new Position(70.0, 80.0));\n        \n        DelegatingParcelTracker tracker = new DelegatingParcelTracker(initialData);\n        \n        // Create a fixed thread pool with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Create concurrent tasks\n        Runnable updateTask1 = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String packageId = \"PKG001\";\n                Position oldPos = tracker.getPosition(packageId);\n                if (oldPos != null) {\n                    Position newPos = new Position(oldPos.x + i * 10, oldPos.y + i * 10);\n                    boolean success = tracker.assignPosition(packageId, newPos);\n                    System.out.println(threadName + \" - Updated \" + packageId + \n                                     \" to \" + newPos + \": \" + success);\n                }\n                \n                packageId = \"PKG002\";\n                oldPos = tracker.getPosition(packageId);\n                if (oldPos != null) {\n                    Position newPos = new Position(oldPos.x - i * 5, oldPos.y - i * 5);\n                    boolean success = tracker.assignPosition(packageId, newPos);\n                    System.out.println(threadName + \" - Updated \" + packageId + \n                                     \" to \" + newPos + \": \" + success);\n                }\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        Runnable updateTask2 = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                String packageId = \"PKG003\";\n                Position oldPos = tracker.getPosition(packageId);\n                if (oldPos != null) {\n                    Position newPos = new Position(oldPos.x + i * 15, oldPos.y - i * 15);\n                    boolean success = tracker.assignPosition(packageId, newPos);\n                    System.out.println(threadName + \" - Updated \" + packageId + \n                                     \" to \" + newPos + \": \" + success);\n                }\n                \n                // Try to update a non-existent package\n                boolean failedUpdate = tracker.assignPosition(\"PKG999\", new Position(100, 100));\n                System.out.println(threadName + \" - Attempted to update non-existent PKG999: \" + failedUpdate);\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> future1 = executor.submit(updateTask1);\n        Future<?> future2 = executor.submit(updateTask2);\n        \n        // Main thread also performs some operations\n        System.out.println(\"\\nMain thread operations:\");\n        for (int i = 0; i < 3; i++) {\n            // Get snapshot and live view\n            Map<String, Position> snapshot = tracker.getStaticSnapshot();\n            Map<String, Position> liveView = tracker.getLiveUnmodifiableView();\n            \n            System.out.println(\"\\n--- Iteration \" + i + \" ---\");\n            System.out.println(\"Snapshot size: \" + snapshot.size());\n            System.out.println(\"Live view size: \" + liveView.size());\n            \n            // Update PKG004\n            Position pkg4Pos = tracker.getPosition(\"PKG004\");\n            if (pkg4Pos != null) {\n                Position newPos = new Position(pkg4Pos.x + i * 20, pkg4Pos.y + i * 20);\n                boolean success = tracker.assignPosition(\"PKG004\", newPos);\n                System.out.println(\"Main thread - Updated PKG004 to \" + newPos + \": \" + success);\n            }\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                break;\n            }\n        }\n        \n        // Wait for tasks to complete\n        try {\n            future1.get(3, TimeUnit.SECONDS);\n            future2.get(3, TimeUnit.SECONDS);\n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error waiting for tasks: \" + e.getMessage());\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        // Print final state\n        System.out.println(\"\\n=== Final Package Positions ===\");\n        Map<String, Position> finalSnapshot = tracker.getStaticSnapshot();\n        finalSnapshot.forEach((id, pos) -> \n            System.out.println(id + \": \" + pos));\n        \n        // Demonstrate that live view reflects changes\n        System.out.println(\"\\n=== Testing Live View vs Snapshot ===\");\n        Map<String, Position> liveView = tracker.getLiveUnmodifiableView();\n        Map<String, Position> staticSnapshot = tracker.getStaticSnapshot();\n        \n        System.out.println(\"Before update - PKG001 in live view: \" + liveView.get(\"PKG001\"));\n        System.out.println(\"Before update - PKG001 in snapshot: \" + staticSnapshot.get(\"PKG001\"));\n        \n        tracker.assignPosition(\"PKG001\", new Position(999, 999));\n        \n        System.out.println(\"After update - PKG001 in live view: \" + liveView.get(\"PKG001\"));\n        System.out.println(\"After update - PKG001 in snapshot: \" + staticSnapshot.get(\"PKG001\"));\n        \n        // Try to modify unmodifiable maps (will throw exception)\n        try {\n            liveView.put(\"PKG001\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"\\nCorrectly prevented modification of live view\");\n        }\n        \n        try {\n            staticSnapshot.put(\"PKG001\", new Position(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Correctly prevented modification of snapshot\");\n        }\n    }\n}\n\nclass Position {\n    final double x;\n    final double y;\n    \n    public Position(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"Position(%.1f, %.1f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Position position = (Position) obj;\n        return Double.compare(position.x, x) == 0 && \n               Double.compare(position.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n```\n\nThis implementation provides:\n\n1. **Thread-safe package tracking** using `ConcurrentHashMap` with delegation pattern\n2. **Position retrieval** via `getPosition()`\n3. **Position assignment** via `assignPosition()` that only succeeds for existing package IDs\n4. **Two view methods**:\n   - `getLiveUnmodifiableView()`: Returns a live unmodifiable view backed by the original data\n   - `getStaticSnapshot()`: Returns a static snapshot as an unmodifiable map\n5. **Concurrent execution** with exactly 3 threads total (main + 2 worker threads)\n6. **Thread safety** without explicit synchronization, relying on ConcurrentHashMap's thread-safe operations\n7. **Demonstration** of concurrent updates and the difference between live view and snapshot\n\nThe program uses a fixed thread pool with 2 threads, ensuring the total thread count (including main) doesn't exceed 3. The delegation pattern ensures thread safety by delegating all operations to the thread-safe `ConcurrentHashMap`."
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Returning a static copy of the location set instead of a 'live' one. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called DelegatingRobotTracker that monitors the coordinates of robots in a thread-safe manner using a ConcurrentHashMap. The class should provide methods to check the coordinates of a specific robot, modify the coordinates of a robot, and return an unmodifiable view of all robot coordinates. Use delegation to ensure thread safety without explicitly synchronizing methods. Initialize the tracker with a map of robot IDs to their initial coordinates. Include two versions of the method to retrieve all coordinates: one that returns a live unmodifiable map backed by the original data, and another that returns a static snapshot of the current state as an unmodifiable map. Ensure that modifying a robot's coordinates only succeeds if the robot ID already exists in the map. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingRobotTracker {\n    private final ConcurrentHashMap<String, Coordinates> robotLocations;\n    \n    public DelegatingRobotTracker(Map<String, Coordinates> initialLocations) {\n        this.robotLocations = new ConcurrentHashMap<>(initialLocations);\n    }\n    \n    public Coordinates getCoordinates(String robotId) {\n        Coordinates coords = robotLocations.get(robotId);\n        return coords != null ? new Coordinates(coords.x, coords.y) : null;\n    }\n    \n    public boolean updateCoordinates(String robotId, int newX, int newY) {\n        return robotLocations.computeIfPresent(robotId, (id, oldCoords) -> \n            new Coordinates(newX, newY)) != null;\n    }\n    \n    public Map<String, Coordinates> getLiveUnmodifiableView() {\n        return Collections.unmodifiableMap(robotLocations);\n    }\n    \n    public Map<String, Coordinates> getSnapshotUnmodifiableView() {\n        Map<String, Coordinates> snapshot = new HashMap<>();\n        robotLocations.forEach((id, coords) -> \n            snapshot.put(id, new Coordinates(coords.x, coords.y)));\n        return Collections.unmodifiableMap(snapshot);\n    }\n    \n    public static void main(String[] args) {\n        Map<String, Coordinates> initialPositions = new HashMap<>();\n        initialPositions.put(\"Robot1\", new Coordinates(0, 0));\n        initialPositions.put(\"Robot2\", new Coordinates(10, 20));\n        initialPositions.put(\"Robot3\", new Coordinates(30, 40));\n        \n        DelegatingRobotTracker tracker = new DelegatingRobotTracker(initialPositions);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable updateTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            Random random = new Random();\n            \n            for (int i = 0; i < 5; i++) {\n                String robotId = \"Robot\" + (random.nextInt(3) + 1);\n                int newX = random.nextInt(100);\n                int newY = random.nextInt(100);\n                \n                boolean updated = tracker.updateCoordinates(robotId, newX, newY);\n                System.out.println(threadName + \" - Updating \" + robotId + \n                    \" to (\" + newX + \", \" + newY + \") - Success: \" + updated);\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        Runnable readTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            \n            for (int i = 0; i < 5; i++) {\n                System.out.println(threadName + \" - Current robot positions:\");\n                Map<String, Coordinates> snapshot = tracker.getSnapshotUnmodifiableView();\n                snapshot.forEach((id, coords) -> \n                    System.out.println(\"  \" + id + \": \" + coords));\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        Future<?> updateFuture = executor.submit(updateTask);\n        Future<?> readFuture = executor.submit(readTask);\n        \n        System.out.println(\"Main thread - Initial positions:\");\n        Map<String, Coordinates> liveView = tracker.getLiveUnmodifiableView();\n        liveView.forEach((id, coords) -> \n            System.out.println(\"  \" + id + \": \" + coords));\n        \n        System.out.println(\"\\nMain thread - Testing update for non-existent robot:\");\n        boolean nonExistentUpdate = tracker.updateCoordinates(\"Robot99\", 50, 50);\n        System.out.println(\"Update Robot99 success: \" + nonExistentUpdate);\n        \n        System.out.println(\"\\nMain thread - Getting specific robot coordinates:\");\n        Coordinates robot1Coords = tracker.getCoordinates(\"Robot1\");\n        System.out.println(\"Robot1 coordinates: \" + robot1Coords);\n        \n        try {\n            updateFuture.get(2, TimeUnit.SECONDS);\n            readFuture.get(2, TimeUnit.SECONDS);\n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error waiting for tasks: \" + e.getMessage());\n        }\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"\\nMain thread - Final positions:\");\n        Map<String, Coordinates> finalSnapshot = tracker.getSnapshotUnmodifiableView();\n        finalSnapshot.forEach((id, coords) -> \n            System.out.println(\"  \" + id + \": \" + coords));\n        \n        System.out.println(\"\\nMain thread - Testing immutability of snapshot:\");\n        try {\n            finalSnapshot.put(\"Robot4\", new Coordinates(100, 100));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Snapshot is properly immutable: \" + e.getClass().getSimpleName());\n        }\n        \n        System.out.println(\"\\nMain thread - Testing immutability of live view:\");\n        try {\n            liveView.put(\"Robot4\", new Coordinates(100, 100));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Live view is properly immutable: \" + e.getClass().getSimpleName());\n        }\n    }\n}\n\nclass Coordinates {\n    public final int x;\n    public final int y;\n    \n    public Coordinates(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    @Override\n    public String toString() {\n        return \"(\" + x + \", \" + y + \")\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Coordinates that = (Coordinates) obj;\n        return x == that.x && y == that.y;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Coordinate {\n    private final double x;\n    private final double y;\n    \n    public Coordinate(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public double getX() {\n        return x;\n    }\n    \n    public double getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"(%.2f, %.2f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Coordinate that = (Coordinate) obj;\n        return Double.compare(that.x, x) == 0 && Double.compare(that.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n\nclass DelegatingRobotTracker {\n    private final ConcurrentHashMap<String, Coordinate> robotLocations;\n    \n    public DelegatingRobotTracker(Map<String, Coordinate> initialLocations) {\n        this.robotLocations = new ConcurrentHashMap<>(initialLocations);\n    }\n    \n    public Coordinate getLocation(String robotId) {\n        return robotLocations.get(robotId);\n    }\n    \n    public boolean updateLocation(String robotId, Coordinate newLocation) {\n        if (newLocation == null) {\n            throw new IllegalArgumentException(\"Coordinate cannot be null\");\n        }\n        \n        // Only update if the robot ID exists\n        return robotLocations.replace(robotId, robotLocations.get(robotId), newLocation);\n    }\n    \n    public boolean updateLocationIfExists(String robotId, Coordinate newLocation) {\n        if (newLocation == null) {\n            throw new IllegalArgumentException(\"Coordinate cannot be null\");\n        }\n        \n        // Alternative implementation using computeIfPresent\n        return robotLocations.computeIfPresent(robotId, (k, v) -> newLocation) != null;\n    }\n    \n    public Map<String, Coordinate> getLiveUnmodifiableView() {\n        return Collections.unmodifiableMap(robotLocations);\n    }\n    \n    public Map<String, Coordinate> getStaticSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(robotLocations));\n    }\n    \n    public int getRobotCount() {\n        return robotLocations.size();\n    }\n    \n    public boolean containsRobot(String robotId) {\n        return robotLocations.containsKey(robotId);\n    }\n}\n\npublic class RobotTrackerDemo {\n    \n    public static void main(String[] args) {\n        // Initialize robot tracker with initial coordinates\n        Map<String, Coordinate> initialLocations = new HashMap<>();\n        initialLocations.put(\"Robot-A\", new Coordinate(0.0, 0.0));\n        initialLocations.put(\"Robot-B\", new Coordinate(10.0, 10.0));\n        initialLocations.put(\"Robot-C\", new Coordinate(20.0, 20.0));\n        \n        DelegatingRobotTracker tracker = new DelegatingRobotTracker(initialLocations);\n        \n        System.out.println(\"=== Robot Tracker Demonstration ===\");\n        System.out.println(\"Initial robot positions:\");\n        printRobotPositions(tracker.getStaticSnapshot());\n        \n        // Create an ExecutorService with exactly 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Task 1: Continuously update Robot-A's position\n        Runnable updateTask1 = () -> {\n            String robotId = \"Robot-A\";\n            Random random = new Random();\n            for (int i = 0; i < 5; i++) {\n                double newX = random.nextDouble() * 50;\n                double newY = random.nextDouble() * 50;\n                Coordinate newCoord = new Coordinate(newX, newY);\n                \n                boolean updated = tracker.updateLocation(robotId, newCoord);\n                if (updated) {\n                    System.out.printf(\"[Thread-%s] Updated %s to %s%n\", \n                        Thread.currentThread().getName(), robotId, newCoord);\n                }\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Task 2: Continuously update Robot-B's position and read Robot-C\n        Runnable updateTask2 = () -> {\n            String robotIdToUpdate = \"Robot-B\";\n            String robotIdToRead = \"Robot-C\";\n            Random random = new Random();\n            \n            for (int i = 0; i < 5; i++) {\n                // Update Robot-B\n                double newX = random.nextDouble() * 50;\n                double newY = random.nextDouble() * 50;\n                Coordinate newCoord = new Coordinate(newX, newY);\n                \n                boolean updated = tracker.updateLocationIfExists(robotIdToUpdate, newCoord);\n                if (updated) {\n                    System.out.printf(\"[Thread-%s] Updated %s to %s%n\", \n                        Thread.currentThread().getName(), robotIdToUpdate, newCoord);\n                }\n                \n                // Read Robot-C's position\n                Coordinate robotCPosition = tracker.getLocation(robotIdToRead);\n                System.out.printf(\"[Thread-%s] Read %s position: %s%n\", \n                    Thread.currentThread().getName(), robotIdToRead, robotCPosition);\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> future1 = executor.submit(updateTask1);\n        Future<?> future2 = executor.submit(updateTask2);\n        \n        // Main thread: Try to update a non-existent robot and monitor changes\n        System.out.println(\"\\n[Main Thread] Attempting to update non-existent Robot-D...\");\n        boolean nonExistentUpdate = tracker.updateLocation(\"Robot-D\", new Coordinate(100, 100));\n        System.out.println(\"[Main Thread] Update result for Robot-D: \" + nonExistentUpdate);\n        \n        // Main thread: Monitor live view\n        Map<String, Coordinate> liveView = tracker.getLiveUnmodifiableView();\n        System.out.println(\"\\n[Main Thread] Got live unmodifiable view\");\n        \n        try {\n            Thread.sleep(300);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        // Main thread: Update Robot-C\n        System.out.println(\"\\n[Main Thread] Updating Robot-C position...\");\n        tracker.updateLocation(\"Robot-C\", new Coordinate(35.5, 42.7));\n        \n        // Wait for tasks to complete\n        try {\n            future1.get(2, TimeUnit.SECONDS);\n            future2.get(2, TimeUnit.SECONDS);\n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error waiting for tasks: \" + e.getMessage());\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        // Display final results\n        System.out.println(\"\\n=== Final Results ===\");\n        System.out.println(\"Final robot positions (static snapshot):\");\n        printRobotPositions(tracker.getStaticSnapshot());\n        \n        System.out.println(\"\\nLive view still shows current state:\");\n        printRobotPositions(liveView);\n        \n        // Demonstrate that snapshot is immutable and independent\n        System.out.println(\"\\n=== Testing Snapshot Independence ===\");\n        Map<String, Coordinate> snapshot1 = tracker.getStaticSnapshot();\n        System.out.println(\"Snapshot 1 taken\");\n        \n        tracker.updateLocation(\"Robot-A\", new Coordinate(99.9, 99.9));\n        System.out.println(\"Updated Robot-A to (99.9, 99.9)\");\n        \n        Map<String, Coordinate> snapshot2 = tracker.getStaticSnapshot();\n        System.out.println(\"\\nSnapshot 1 (before update): Robot-A = \" + snapshot1.get(\"Robot-A\"));\n        System.out.println(\"Snapshot 2 (after update): Robot-A = \" + snapshot2.get(\"Robot-A\"));\n        System.out.println(\"Live view (current): Robot-A = \" + liveView.get(\"Robot-A\"));\n        \n        // Try to modify unmodifiable map (will throw exception)\n        System.out.println(\"\\n=== Testing Unmodifiability ===\");\n        try {\n            liveView.put(\"Robot-X\", new Coordinate(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Live view is unmodifiable: \" + e.getClass().getSimpleName());\n        }\n        \n        try {\n            snapshot1.put(\"Robot-Y\", new Coordinate(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Snapshot is unmodifiable: \" + e.getClass().getSimpleName());\n        }\n        \n        System.out.println(\"\\n=== Demonstration Complete ===\");\n        System.out.println(\"Total robots tracked: \" + tracker.getRobotCount());\n        System.out.println(\"Contains Robot-A: \" + tracker.containsRobot(\"Robot-A\"));\n        System.out.println(\"Contains Robot-D: \" + tracker.containsRobot(\"Robot-D\"));\n    }\n    \n    private static void printRobotPositions(Map<String, Coordinate> positions) {\n        positions.forEach((id, coord) -> \n            System.out.printf(\"  %s: %s%n\", id, coord));\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingRobotTracker {\n    private final ConcurrentHashMap<String, Coordinates> robotLocations;\n    \n    public DelegatingRobotTracker(Map<String, Coordinates> initialLocations) {\n        this.robotLocations = new ConcurrentHashMap<>(initialLocations);\n    }\n    \n    public Coordinates getCoordinates(String robotId) {\n        Coordinates coords = robotLocations.get(robotId);\n        return coords != null ? new Coordinates(coords.x, coords.y) : null;\n    }\n    \n    public boolean updateCoordinates(String robotId, double x, double y) {\n        return robotLocations.computeIfPresent(robotId, (key, oldCoords) -> \n            new Coordinates(x, y)) != null;\n    }\n    \n    public Map<String, Coordinates> getLiveUnmodifiableView() {\n        return Collections.unmodifiableMap(robotLocations);\n    }\n    \n    public Map<String, Coordinates> getStaticSnapshot() {\n        Map<String, Coordinates> snapshot = new HashMap<>();\n        robotLocations.forEach((id, coords) -> \n            snapshot.put(id, new Coordinates(coords.x, coords.y)));\n        return Collections.unmodifiableMap(snapshot);\n    }\n    \n    public static void main(String[] args) {\n        // Initialize tracker with some robots\n        Map<String, Coordinates> initialPositions = new HashMap<>();\n        initialPositions.put(\"Robot1\", new Coordinates(0.0, 0.0));\n        initialPositions.put(\"Robot2\", new Coordinates(10.0, 20.0));\n        initialPositions.put(\"Robot3\", new Coordinates(30.0, 40.0));\n        \n        DelegatingRobotTracker tracker = new DelegatingRobotTracker(initialPositions);\n        \n        // Create executor service with 2 worker threads (total 3 threads including main)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // CountDownLatch to synchronize thread completion\n        CountDownLatch latch = new CountDownLatch(2);\n        \n        // Thread 1: Continuously update Robot1's position\n        executor.submit(() -> {\n            try {\n                Random random = new Random();\n                for (int i = 0; i < 10; i++) {\n                    double newX = random.nextDouble() * 100;\n                    double newY = random.nextDouble() * 100;\n                    boolean updated = tracker.updateCoordinates(\"Robot1\", newX, newY);\n                    System.out.println(\"Thread 1 - Updated Robot1: \" + updated + \n                                     \" to (\" + newX + \", \" + newY + \")\");\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        // Thread 2: Read and update Robot2 and Robot3\n        executor.submit(() -> {\n            try {\n                Random random = new Random();\n                for (int i = 0; i < 10; i++) {\n                    // Read Robot2's current position\n                    Coordinates robot2Coords = tracker.getCoordinates(\"Robot2\");\n                    if (robot2Coords != null) {\n                        System.out.println(\"Thread 2 - Robot2 at: \" + robot2Coords);\n                    }\n                    \n                    // Update Robot3's position\n                    double newX = random.nextDouble() * 50;\n                    double newY = random.nextDouble() * 50;\n                    boolean updated = tracker.updateCoordinates(\"Robot3\", newX, newY);\n                    System.out.println(\"Thread 2 - Updated Robot3: \" + updated + \n                                     \" to (\" + newX + \", \" + newY + \")\");\n                    \n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        // Main thread: Monitor the state periodically\n        try {\n            for (int i = 0; i < 5; i++) {\n                Thread.sleep(300);\n                System.out.println(\"\\n=== Main Thread - Current State ===\");\n                \n                // Get live view\n                Map<String, Coordinates> liveView = tracker.getLiveUnmodifiableView();\n                System.out.println(\"Live view size: \" + liveView.size());\n                \n                // Get static snapshot\n                Map<String, Coordinates> snapshot = tracker.getStaticSnapshot();\n                System.out.println(\"Snapshot:\");\n                snapshot.forEach((id, coords) -> \n                    System.out.println(\"  \" + id + \": \" + coords));\n                \n                // Try to update a non-existent robot (should fail)\n                boolean invalidUpdate = tracker.updateCoordinates(\"Robot99\", 0, 0);\n                System.out.println(\"Update non-existent Robot99: \" + invalidUpdate);\n                System.out.println(\"=====================================\\n\");\n            }\n            \n            // Wait for worker threads to complete\n            latch.await();\n            \n            // Final state\n            System.out.println(\"\\n=== Final State ===\");\n            Map<String, Coordinates> finalSnapshot = tracker.getStaticSnapshot();\n            finalSnapshot.forEach((id, coords) -> \n                System.out.println(id + \": \" + coords));\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        } finally {\n            executor.shutdown();\n            try {\n                if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                    executor.shutdownNow();\n                }\n            } catch (InterruptedException e) {\n                executor.shutdownNow();\n            }\n        }\n    }\n}\n\nclass Coordinates {\n    final double x;\n    final double y;\n    \n    public Coordinates(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"(%.2f, %.2f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Coordinates that = (Coordinates) obj;\n        return Double.compare(that.x, x) == 0 && \n               Double.compare(that.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}"
        ],
        "graded_list": [
            true,
            false,
            false
        ],
        "ground_truth": "import java.awt.Point;\nimport java.util.*;\nimport java.util.concurrent.*;\n\n/**\n* DelegatingVehicleTracker\n* Delegates thread safety to a ConcurrentHashMap.\n*/\npublic class DelegatingVehicleTracker {\n\nprivate final ConcurrentMap<String, Point> locations;\nprivate final Map<String, Point> unmodifiableMap;\n\npublic DelegatingVehicleTracker(Map<String, Point> points) {\nlocations = new ConcurrentHashMap<>(points);\nunmodifiableMap = Collections.unmodifiableMap(locations);\n}\n\npublic Map<String, Point> getLocations() {\nreturn unmodifiableMap;\n}\n\n\npublic void setLocation(String id, int x, int y) {\nif (locations.replace(id, new Point(x, y)) == null)\nthrow new IllegalArgumentException(\"Invalid vehicle name: \" + id);\n}\n\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, Point> initialVehicles = new HashMap<>();\ninitialVehicles.put(\"V1\", new Point(0, 0));\ninitialVehicles.put(\"V2\", new Point(0, 0));\ninitialVehicles.put(\"V3\", new Point(0, 0));\n\nDelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialVehicles);\n\n// Reduce threads to 2 for JPF-friendly execution\nThread[] threads = new Thread[2];\n\nfor (int i = 0; i < 2; i++) {\nfinal String vehicleId = \"V\" + ((i % 3) + 1);\nthreads[i] = new Thread(() -> {\ntry {\n// Reduce iterations to 2 per thread\nfor (int j = 0; j < 2; j++) {\n// Use deterministic fixed values instead of random\nint x = j * 10 + 5;\nint y = j * 20 + 5;\ntracker.setLocation(vehicleId, x, y);\nSystem.out.println(Thread.currentThread().getName() +\n\" updated \" + vehicleId + \" to (\" + x + \", \" + y + \")\");\nThread.sleep(10);\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\ntracker.getLocations().forEach((id, point) ->\nSystem.out.println(id + \": (\" + point.x + \", \" + point.y + \")\"));\n}\n}",
        "max_depth": "57",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 57.37%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.52%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.51%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=124715,visited=137477,backtracked=261622,end=0\nsearch:             maxDepth=570,constraints=72103\nchoice generators:  thread=87774 (signal=0,lock=86,sharedRef=83707,threadApi=77,reschedule=0), data=0\nheap:               new=719619,released=200416,maxLive=882,gcCycles=252478\ninstructions:       24047040\nmax memory:         1020MB\nloaded code:        classes=157,methods=2657\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.NullPointerException  at java.util.concu...\"\n\n====================================================== statistics\nstates:             new=4,visited=0,backtracked=0,end=0\nsearch:             maxDepth=4,constraints=0\nchoice generators:  thread=4 (signal=0,lock=2,sharedRef=0,threadApi=2,reschedule=0), data=0\nheap:               new=907,released=61,maxLive=820,gcCycles=3\ninstructions:       12651\nmax memory:         981MB\nloaded code:        classes=154,methods=2653\n\n====================================================== search finished",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "no errors detected",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.NullPointerException  at java.util.concu...\"",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nDelegatingRobotTracker.main()\n====================================================== search started: 11/16/25 4:20 PM\n=== Main Thread - Current State ===\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            55.86,
            63.35,
            53.44
        ],
        "llm_output": [
            "Here's a complete Java 8 implementation that meets all your requirements:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingRobotTracker {\n    private final ConcurrentHashMap<String, Coordinates> robotLocations;\n    \n    public DelegatingRobotTracker(Map<String, Coordinates> initialLocations) {\n        this.robotLocations = new ConcurrentHashMap<>(initialLocations);\n    }\n    \n    public Coordinates getCoordinates(String robotId) {\n        Coordinates coords = robotLocations.get(robotId);\n        return coords != null ? new Coordinates(coords.x, coords.y) : null;\n    }\n    \n    public boolean updateCoordinates(String robotId, int newX, int newY) {\n        return robotLocations.computeIfPresent(robotId, (id, oldCoords) -> \n            new Coordinates(newX, newY)) != null;\n    }\n    \n    public Map<String, Coordinates> getLiveUnmodifiableView() {\n        return Collections.unmodifiableMap(robotLocations);\n    }\n    \n    public Map<String, Coordinates> getSnapshotUnmodifiableView() {\n        Map<String, Coordinates> snapshot = new HashMap<>();\n        robotLocations.forEach((id, coords) -> \n            snapshot.put(id, new Coordinates(coords.x, coords.y)));\n        return Collections.unmodifiableMap(snapshot);\n    }\n    \n    public static void main(String[] args) {\n        Map<String, Coordinates> initialPositions = new HashMap<>();\n        initialPositions.put(\"Robot1\", new Coordinates(0, 0));\n        initialPositions.put(\"Robot2\", new Coordinates(10, 20));\n        initialPositions.put(\"Robot3\", new Coordinates(30, 40));\n        \n        DelegatingRobotTracker tracker = new DelegatingRobotTracker(initialPositions);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable updateTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            Random random = new Random();\n            \n            for (int i = 0; i < 5; i++) {\n                String robotId = \"Robot\" + (random.nextInt(3) + 1);\n                int newX = random.nextInt(100);\n                int newY = random.nextInt(100);\n                \n                boolean updated = tracker.updateCoordinates(robotId, newX, newY);\n                System.out.println(threadName + \" - Updating \" + robotId + \n                    \" to (\" + newX + \", \" + newY + \") - Success: \" + updated);\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        Runnable readTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            \n            for (int i = 0; i < 5; i++) {\n                System.out.println(threadName + \" - Current robot positions:\");\n                Map<String, Coordinates> snapshot = tracker.getSnapshotUnmodifiableView();\n                snapshot.forEach((id, coords) -> \n                    System.out.println(\"  \" + id + \": \" + coords));\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        Future<?> updateFuture = executor.submit(updateTask);\n        Future<?> readFuture = executor.submit(readTask);\n        \n        System.out.println(\"Main thread - Initial positions:\");\n        Map<String, Coordinates> liveView = tracker.getLiveUnmodifiableView();\n        liveView.forEach((id, coords) -> \n            System.out.println(\"  \" + id + \": \" + coords));\n        \n        System.out.println(\"\\nMain thread - Testing update for non-existent robot:\");\n        boolean nonExistentUpdate = tracker.updateCoordinates(\"Robot99\", 50, 50);\n        System.out.println(\"Update Robot99 success: \" + nonExistentUpdate);\n        \n        System.out.println(\"\\nMain thread - Getting specific robot coordinates:\");\n        Coordinates robot1Coords = tracker.getCoordinates(\"Robot1\");\n        System.out.println(\"Robot1 coordinates: \" + robot1Coords);\n        \n        try {\n            updateFuture.get(2, TimeUnit.SECONDS);\n            readFuture.get(2, TimeUnit.SECONDS);\n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error waiting for tasks: \" + e.getMessage());\n        }\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"\\nMain thread - Final positions:\");\n        Map<String, Coordinates> finalSnapshot = tracker.getSnapshotUnmodifiableView();\n        finalSnapshot.forEach((id, coords) -> \n            System.out.println(\"  \" + id + \": \" + coords));\n        \n        System.out.println(\"\\nMain thread - Testing immutability of snapshot:\");\n        try {\n            finalSnapshot.put(\"Robot4\", new Coordinates(100, 100));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Snapshot is properly immutable: \" + e.getClass().getSimpleName());\n        }\n        \n        System.out.println(\"\\nMain thread - Testing immutability of live view:\");\n        try {\n            liveView.put(\"Robot4\", new Coordinates(100, 100));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Live view is properly immutable: \" + e.getClass().getSimpleName());\n        }\n    }\n}\n\nclass Coordinates {\n    public final int x;\n    public final int y;\n    \n    public Coordinates(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    @Override\n    public String toString() {\n        return \"(\" + x + \", \" + y + \")\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Coordinates that = (Coordinates) obj;\n        return x == that.x && y == that.y;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n```\n\nThis implementation provides:\n\n1. **Thread-safe robot tracking** using `ConcurrentHashMap` for delegation without explicit synchronization\n2. **Immutable `Coordinates` class** to prevent coordinate modification after creation\n3. **`getCoordinates()`** method that returns a defensive copy of coordinates\n4. **`updateCoordinates()`** method that only updates existing robots using `computeIfPresent()`\n5. **`getLiveUnmodifiableView()`** that returns a live unmodifiable view backed by the original map\n6. **`getSnapshotUnmodifiableView()`** that returns a static snapshot as an unmodifiable map\n7. **Concurrent testing** with exactly 3 threads total (main thread + 2 worker threads from fixed thread pool)\n8. **Proper thread management** with executor shutdown and cleanup\n9. **Demonstration** of thread-safe concurrent reads and writes to the robot tracker\n\nThe program uses delegation to `ConcurrentHashMap` for thread safety, avoiding explicit synchronization while ensuring all operations are atomic and thread-safe.",
            "Here's a complete implementation of the DelegatingRobotTracker with concurrent testing:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Coordinate {\n    private final double x;\n    private final double y;\n    \n    public Coordinate(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public double getX() {\n        return x;\n    }\n    \n    public double getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"(%.2f, %.2f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Coordinate that = (Coordinate) obj;\n        return Double.compare(that.x, x) == 0 && Double.compare(that.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n\nclass DelegatingRobotTracker {\n    private final ConcurrentHashMap<String, Coordinate> robotLocations;\n    \n    public DelegatingRobotTracker(Map<String, Coordinate> initialLocations) {\n        this.robotLocations = new ConcurrentHashMap<>(initialLocations);\n    }\n    \n    public Coordinate getLocation(String robotId) {\n        return robotLocations.get(robotId);\n    }\n    \n    public boolean updateLocation(String robotId, Coordinate newLocation) {\n        if (newLocation == null) {\n            throw new IllegalArgumentException(\"Coordinate cannot be null\");\n        }\n        \n        // Only update if the robot ID exists\n        return robotLocations.replace(robotId, robotLocations.get(robotId), newLocation);\n    }\n    \n    public boolean updateLocationIfExists(String robotId, Coordinate newLocation) {\n        if (newLocation == null) {\n            throw new IllegalArgumentException(\"Coordinate cannot be null\");\n        }\n        \n        // Alternative implementation using computeIfPresent\n        return robotLocations.computeIfPresent(robotId, (k, v) -> newLocation) != null;\n    }\n    \n    public Map<String, Coordinate> getLiveUnmodifiableView() {\n        return Collections.unmodifiableMap(robotLocations);\n    }\n    \n    public Map<String, Coordinate> getStaticSnapshot() {\n        return Collections.unmodifiableMap(new HashMap<>(robotLocations));\n    }\n    \n    public int getRobotCount() {\n        return robotLocations.size();\n    }\n    \n    public boolean containsRobot(String robotId) {\n        return robotLocations.containsKey(robotId);\n    }\n}\n\npublic class RobotTrackerDemo {\n    \n    public static void main(String[] args) {\n        // Initialize robot tracker with initial coordinates\n        Map<String, Coordinate> initialLocations = new HashMap<>();\n        initialLocations.put(\"Robot-A\", new Coordinate(0.0, 0.0));\n        initialLocations.put(\"Robot-B\", new Coordinate(10.0, 10.0));\n        initialLocations.put(\"Robot-C\", new Coordinate(20.0, 20.0));\n        \n        DelegatingRobotTracker tracker = new DelegatingRobotTracker(initialLocations);\n        \n        System.out.println(\"=== Robot Tracker Demonstration ===\");\n        System.out.println(\"Initial robot positions:\");\n        printRobotPositions(tracker.getStaticSnapshot());\n        \n        // Create an ExecutorService with exactly 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Task 1: Continuously update Robot-A's position\n        Runnable updateTask1 = () -> {\n            String robotId = \"Robot-A\";\n            Random random = new Random();\n            for (int i = 0; i < 5; i++) {\n                double newX = random.nextDouble() * 50;\n                double newY = random.nextDouble() * 50;\n                Coordinate newCoord = new Coordinate(newX, newY);\n                \n                boolean updated = tracker.updateLocation(robotId, newCoord);\n                if (updated) {\n                    System.out.printf(\"[Thread-%s] Updated %s to %s%n\", \n                        Thread.currentThread().getName(), robotId, newCoord);\n                }\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Task 2: Continuously update Robot-B's position and read Robot-C\n        Runnable updateTask2 = () -> {\n            String robotIdToUpdate = \"Robot-B\";\n            String robotIdToRead = \"Robot-C\";\n            Random random = new Random();\n            \n            for (int i = 0; i < 5; i++) {\n                // Update Robot-B\n                double newX = random.nextDouble() * 50;\n                double newY = random.nextDouble() * 50;\n                Coordinate newCoord = new Coordinate(newX, newY);\n                \n                boolean updated = tracker.updateLocationIfExists(robotIdToUpdate, newCoord);\n                if (updated) {\n                    System.out.printf(\"[Thread-%s] Updated %s to %s%n\", \n                        Thread.currentThread().getName(), robotIdToUpdate, newCoord);\n                }\n                \n                // Read Robot-C's position\n                Coordinate robotCPosition = tracker.getLocation(robotIdToRead);\n                System.out.printf(\"[Thread-%s] Read %s position: %s%n\", \n                    Thread.currentThread().getName(), robotIdToRead, robotCPosition);\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> future1 = executor.submit(updateTask1);\n        Future<?> future2 = executor.submit(updateTask2);\n        \n        // Main thread: Try to update a non-existent robot and monitor changes\n        System.out.println(\"\\n[Main Thread] Attempting to update non-existent Robot-D...\");\n        boolean nonExistentUpdate = tracker.updateLocation(\"Robot-D\", new Coordinate(100, 100));\n        System.out.println(\"[Main Thread] Update result for Robot-D: \" + nonExistentUpdate);\n        \n        // Main thread: Monitor live view\n        Map<String, Coordinate> liveView = tracker.getLiveUnmodifiableView();\n        System.out.println(\"\\n[Main Thread] Got live unmodifiable view\");\n        \n        try {\n            Thread.sleep(300);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        // Main thread: Update Robot-C\n        System.out.println(\"\\n[Main Thread] Updating Robot-C position...\");\n        tracker.updateLocation(\"Robot-C\", new Coordinate(35.5, 42.7));\n        \n        // Wait for tasks to complete\n        try {\n            future1.get(2, TimeUnit.SECONDS);\n            future2.get(2, TimeUnit.SECONDS);\n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error waiting for tasks: \" + e.getMessage());\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        // Display final results\n        System.out.println(\"\\n=== Final Results ===\");\n        System.out.println(\"Final robot positions (static snapshot):\");\n        printRobotPositions(tracker.getStaticSnapshot());\n        \n        System.out.println(\"\\nLive view still shows current state:\");\n        printRobotPositions(liveView);\n        \n        // Demonstrate that snapshot is immutable and independent\n        System.out.println(\"\\n=== Testing Snapshot Independence ===\");\n        Map<String, Coordinate> snapshot1 = tracker.getStaticSnapshot();\n        System.out.println(\"Snapshot 1 taken\");\n        \n        tracker.updateLocation(\"Robot-A\", new Coordinate(99.9, 99.9));\n        System.out.println(\"Updated Robot-A to (99.9, 99.9)\");\n        \n        Map<String, Coordinate> snapshot2 = tracker.getStaticSnapshot();\n        System.out.println(\"\\nSnapshot 1 (before update): Robot-A = \" + snapshot1.get(\"Robot-A\"));\n        System.out.println(\"Snapshot 2 (after update): Robot-A = \" + snapshot2.get(\"Robot-A\"));\n        System.out.println(\"Live view (current): Robot-A = \" + liveView.get(\"Robot-A\"));\n        \n        // Try to modify unmodifiable map (will throw exception)\n        System.out.println(\"\\n=== Testing Unmodifiability ===\");\n        try {\n            liveView.put(\"Robot-X\", new Coordinate(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Live view is unmodifiable: \" + e.getClass().getSimpleName());\n        }\n        \n        try {\n            snapshot1.put(\"Robot-Y\", new Coordinate(0, 0));\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Snapshot is unmodifiable: \" + e.getClass().getSimpleName());\n        }\n        \n        System.out.println(\"\\n=== Demonstration Complete ===\");\n        System.out.println(\"Total robots tracked: \" + tracker.getRobotCount());\n        System.out.println(\"Contains Robot-A: \" + tracker.containsRobot(\"Robot-A\"));\n        System.out.println(\"Contains Robot-D: \" + tracker.containsRobot(\"Robot-D\"));\n    }\n    \n    private static void printRobotPositions(Map<String, Coordinate> positions) {\n        positions.forEach((id, coord) -> \n            System.out.printf(\"  %s: %s%n\", id, coord));\n    }\n}\n```\n\nThis implementation provides:\n\n1. **Thread-Safe Robot Tracking**: Uses `ConcurrentHashMap` for thread-safe operations without explicit synchronization.\n\n2. **Coordinate Class**: Immutable class representing robot coordinates with proper `equals`, `hashCode`, and `toString` methods.\n\n3. **DelegatingRobotTracker Features**:\n   - `getLocation()`: Retrieves coordinates for a specific robot\n   - `updateLocation()`: Updates coordinates only if robot exists\n   - `updateLocationIfExists()`: Alternative implementation using `computeIfPresent`\n   - `getLiveUnmodifiableView()`: Returns live unmodifiable view backed by original data\n   - `getStaticSnapshot()`: Returns static snapshot as unmodifiable map\n   - Helper methods for counting and checking robot existence\n\n4. **Concurrent Testing**: \n   - Uses `ExecutorService` with fixed thread pool of 2 threads\n   - Total of 3 threads including main thread (meeting the requirement)\n   - Demonstrates concurrent updates and reads\n   - Shows difference between live view and static snapshot\n\n5. **Thread Safety**: \n   - Delegation to `ConcurrentHashMap` ensures thread safety\n   - No explicit synchronization needed\n   - Immutable `Coordinate` objects prevent shared mutable state issues\n\nThe program demonstrates all required functionality with proper thread safety and concurrent execution.",
            "Here's a complete Java 8 implementation that meets all your requirements:\n\n```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingRobotTracker {\n    private final ConcurrentHashMap<String, Coordinates> robotLocations;\n    \n    public DelegatingRobotTracker(Map<String, Coordinates> initialLocations) {\n        this.robotLocations = new ConcurrentHashMap<>(initialLocations);\n    }\n    \n    public Coordinates getCoordinates(String robotId) {\n        Coordinates coords = robotLocations.get(robotId);\n        return coords != null ? new Coordinates(coords.x, coords.y) : null;\n    }\n    \n    public boolean updateCoordinates(String robotId, double x, double y) {\n        return robotLocations.computeIfPresent(robotId, (key, oldCoords) -> \n            new Coordinates(x, y)) != null;\n    }\n    \n    public Map<String, Coordinates> getLiveUnmodifiableView() {\n        return Collections.unmodifiableMap(robotLocations);\n    }\n    \n    public Map<String, Coordinates> getStaticSnapshot() {\n        Map<String, Coordinates> snapshot = new HashMap<>();\n        robotLocations.forEach((id, coords) -> \n            snapshot.put(id, new Coordinates(coords.x, coords.y)));\n        return Collections.unmodifiableMap(snapshot);\n    }\n    \n    public static void main(String[] args) {\n        // Initialize tracker with some robots\n        Map<String, Coordinates> initialPositions = new HashMap<>();\n        initialPositions.put(\"Robot1\", new Coordinates(0.0, 0.0));\n        initialPositions.put(\"Robot2\", new Coordinates(10.0, 20.0));\n        initialPositions.put(\"Robot3\", new Coordinates(30.0, 40.0));\n        \n        DelegatingRobotTracker tracker = new DelegatingRobotTracker(initialPositions);\n        \n        // Create executor service with 2 worker threads (total 3 threads including main)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // CountDownLatch to synchronize thread completion\n        CountDownLatch latch = new CountDownLatch(2);\n        \n        // Thread 1: Continuously update Robot1's position\n        executor.submit(() -> {\n            try {\n                Random random = new Random();\n                for (int i = 0; i < 10; i++) {\n                    double newX = random.nextDouble() * 100;\n                    double newY = random.nextDouble() * 100;\n                    boolean updated = tracker.updateCoordinates(\"Robot1\", newX, newY);\n                    System.out.println(\"Thread 1 - Updated Robot1: \" + updated + \n                                     \" to (\" + newX + \", \" + newY + \")\");\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        // Thread 2: Read and update Robot2 and Robot3\n        executor.submit(() -> {\n            try {\n                Random random = new Random();\n                for (int i = 0; i < 10; i++) {\n                    // Read Robot2's current position\n                    Coordinates robot2Coords = tracker.getCoordinates(\"Robot2\");\n                    if (robot2Coords != null) {\n                        System.out.println(\"Thread 2 - Robot2 at: \" + robot2Coords);\n                    }\n                    \n                    // Update Robot3's position\n                    double newX = random.nextDouble() * 50;\n                    double newY = random.nextDouble() * 50;\n                    boolean updated = tracker.updateCoordinates(\"Robot3\", newX, newY);\n                    System.out.println(\"Thread 2 - Updated Robot3: \" + updated + \n                                     \" to (\" + newX + \", \" + newY + \")\");\n                    \n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        // Main thread: Monitor the state periodically\n        try {\n            for (int i = 0; i < 5; i++) {\n                Thread.sleep(300);\n                System.out.println(\"\\n=== Main Thread - Current State ===\");\n                \n                // Get live view\n                Map<String, Coordinates> liveView = tracker.getLiveUnmodifiableView();\n                System.out.println(\"Live view size: \" + liveView.size());\n                \n                // Get static snapshot\n                Map<String, Coordinates> snapshot = tracker.getStaticSnapshot();\n                System.out.println(\"Snapshot:\");\n                snapshot.forEach((id, coords) -> \n                    System.out.println(\"  \" + id + \": \" + coords));\n                \n                // Try to update a non-existent robot (should fail)\n                boolean invalidUpdate = tracker.updateCoordinates(\"Robot99\", 0, 0);\n                System.out.println(\"Update non-existent Robot99: \" + invalidUpdate);\n                System.out.println(\"=====================================\\n\");\n            }\n            \n            // Wait for worker threads to complete\n            latch.await();\n            \n            // Final state\n            System.out.println(\"\\n=== Final State ===\");\n            Map<String, Coordinates> finalSnapshot = tracker.getStaticSnapshot();\n            finalSnapshot.forEach((id, coords) -> \n                System.out.println(id + \": \" + coords));\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        } finally {\n            executor.shutdown();\n            try {\n                if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                    executor.shutdownNow();\n                }\n            } catch (InterruptedException e) {\n                executor.shutdownNow();\n            }\n        }\n    }\n}\n\nclass Coordinates {\n    final double x;\n    final double y;\n    \n    public Coordinates(double x, double y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    @Override\n    public String toString() {\n        return String.format(\"(%.2f, %.2f)\", x, y);\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Coordinates that = (Coordinates) obj;\n        return Double.compare(that.x, x) == 0 && \n               Double.compare(that.y, y) == 0;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n```\n\nThis implementation provides:\n\n1. **Thread Safety**: Uses `ConcurrentHashMap` for thread-safe operations without explicit synchronization.\n\n2. **Delegation Pattern**: The class delegates all thread-safety concerns to `ConcurrentHashMap`.\n\n3. **Key Methods**:\n   - `getCoordinates()`: Returns a defensive copy of coordinates for a specific robot\n   - `updateCoordinates()`: Updates coordinates only if the robot ID exists (using `computeIfPresent`)\n   - `getLiveUnmodifiableView()`: Returns an unmodifiable view backed by the original map\n   - `getStaticSnapshot()`: Returns an unmodifiable snapshot with defensive copies\n\n4. **Concurrency Demo**: \n   - Uses exactly 3 threads total (main + 2 worker threads via `ExecutorService`)\n   - Worker threads concurrently read and update robot positions\n   - Main thread monitors the state periodically\n\n5. **Thread Safety Features**:\n   - Immutable `Coordinates` class with final fields\n   - Defensive copying in getter methods\n   - Atomic updates using `computeIfPresent`\n   - No race conditions or data corruption\n\nThe program demonstrates concurrent access patterns while maintaining data consistency through the delegation to `ConcurrentHashMap`'s thread-safe operations."
        ],
        "pass@1": 1.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Candidate for lock elision. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named QuantumQuokkas that represents an immutable collection of the labels of the Quantum Quokkas: \"Zig\", \"Zag\", and \"Zog\". The class should provide two methods:\n\nA method isQuokka(String label) that returns true if the given label is one of the Quantum Quokkas, and false otherwise.\nA method getQuokkaLabels() that returns a string representation of a list containing the labels of the Quantum Quokkas in the order \"Zig\", \"Zag\", \"Zog\".\nEnsure that all fields are properly encapsulated and that the class cannot be modified after construction. Do not make the class thread-unsafe; however, avoid unnecessary synchronization where possible. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class QuantumQuokkas {\n    private final List<String> quokkaLabels;\n    \n    public QuantumQuokkas() {\n        this.quokkaLabels = Collections.unmodifiableList(Arrays.asList(\"Zig\", \"Zag\", \"Zog\"));\n    }\n    \n    public boolean isQuokka(String label) {\n        return quokkaLabels.contains(label);\n    }\n    \n    public String getQuokkaLabels() {\n        return quokkaLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        QuantumQuokkas quantumQuokkas = new QuantumQuokkas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Zig' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zig\"));\n            System.out.println(\"Thread 1: Checking if 'Zag' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zag\"));\n            System.out.println(\"Thread 1: Checking if 'Foo' is a Quokka: \" + quantumQuokkas.isQuokka(\"Foo\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Quokka labels: \" + quantumQuokkas.getQuokkaLabels());\n            System.out.println(\"Thread 2: Checking if 'Zog' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zog\"));\n            System.out.println(\"Thread 2: Checking if 'Bar' is a Quokka: \" + quantumQuokkas.isQuokka(\"Bar\"));\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.Collections;\nimport java.util.LinkedHashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class QuantumQuokkas {\n    private final Set<String> quokkaLabels;\n    \n    public QuantumQuokkas() {\n        Set<String> labels = new LinkedHashSet<>();\n        labels.add(\"Zig\");\n        labels.add(\"Zag\");\n        labels.add(\"Zog\");\n        this.quokkaLabels = Collections.unmodifiableSet(labels);\n    }\n    \n    public boolean isQuokka(String label) {\n        return quokkaLabels.contains(label);\n    }\n    \n    public String getQuokkaLabels() {\n        return quokkaLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        QuantumQuokkas quokkas = new QuantumQuokkas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Zig' is a Quokka: \" + quokkas.isQuokka(\"Zig\"));\n            System.out.println(\"Thread 1: Checking if 'Zag' is a Quokka: \" + quokkas.isQuokka(\"Zag\"));\n            System.out.println(\"Thread 1: Checking if 'Foo' is a Quokka: \" + quokkas.isQuokka(\"Foo\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Quokka labels: \" + quokkas.getQuokkaLabels());\n            System.out.println(\"Thread 2: Checking if 'Zog' is a Quokka: \" + quokkas.isQuokka(\"Zog\"));\n            System.out.println(\"Thread 2: Checking if 'Bar' is a Quokka: \" + quokkas.isQuokka(\"Bar\"));\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class QuantumQuokkas {\n    private final List<String> quokkaLabels;\n    \n    public QuantumQuokkas() {\n        this.quokkaLabels = Collections.unmodifiableList(Arrays.asList(\"Zig\", \"Zag\", \"Zog\"));\n    }\n    \n    public boolean isQuokka(String label) {\n        return quokkaLabels.contains(label);\n    }\n    \n    public String getQuokkaLabels() {\n        return quokkaLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        QuantumQuokkas quantumQuokkas = new QuantumQuokkas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Zig' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zig\"));\n            System.out.println(\"Thread 1: Checking if 'Zag' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zag\"));\n            System.out.println(\"Thread 1: Checking if 'Foo' is a Quokka: \" + quantumQuokkas.isQuokka(\"Foo\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Quokka labels: \" + quantumQuokkas.getQuokkaLabels());\n            System.out.println(\"Thread 2: Checking if 'Zog' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zog\"));\n            System.out.println(\"Thread 2: Checking if 'Bar' is a Quokka: \" + quantumQuokkas.isQuokka(\"Bar\"));\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic final class ThreeStooges {\nprivate static final List<String> STOOGES =\nCollections.unmodifiableList(Arrays.asList(\"Moe\", \"Larry\", \"Curly\"));\nprivate static final Set<String> STOOGES_SET = new HashSet<>(STOOGES);\n\npublic boolean isStooge(String name) {\nreturn STOOGES_SET.contains(name);\n}\n\npublic String getStoogeNames() {\nreturn STOOGES.toString();\n}\n\npublic static void main(String[] args) {\nfinal ThreeStooges stooges = new ThreeStooges();\n\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nString[] namesToCheck = {\"Moe\", \"Shemp\", \"Larry\", \"Curly\", \"John\", \"Curly\", \"Moe\"};\n\nfor (int i = 0; i < namesToCheck.length; i++) {\nfinal int taskId = i;\nfinal String name = namesToCheck[i];\nexecutor.submit(new StoogeCheckerTask(stooges, name, taskId));\n}\n\nexecutor.shutdown();\n}\n}\n\nclass StoogeCheckerTask implements Runnable {\nprivate final ThreeStooges stooges;\nprivate final String name;\nprivate final int taskId;\n\npublic StoogeCheckerTask(ThreeStooges stooges, String name, int taskId) {\nthis.stooges = stooges;\nthis.name = name;\nthis.taskId = taskId;\n}\n\n@Override\npublic void run() {\nSystem.out.println(\"Task ID: \" + taskId + \" - Checking name: \" + name);\nboolean result = stooges.isStooge(name);\nSystem.out.println(\"Task ID: \" + taskId + \" - Is '\" + name + \"' a stooge? \" + result);\n}\n}",
        "max_depth": "158",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.53%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.86%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.08%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=145412,visited=135093,backtracked=279025,end=104\nsearch:             maxDepth=1580,constraints=57121\nchoice generators:  thread=96006 (signal=0,lock=4,sharedRef=58250,threadApi=2,reschedule=24804), data=0\nheap:               new=302563,released=624843,maxLive=766,gcCycles=280505\ninstructions:       35735542\nmax memory:         1017MB\nloaded code:        classes=142,methods=2648\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.99%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.10%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.31%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=146218,visited=134660,backtracked=279357,end=80\nsearch:             maxDepth=1580,constraints=58331\nchoice generators:  thread=95871 (signal=0,lock=4,sharedRef=75403,threadApi=2,reschedule=7384), data=0\nheap:               new=265092,released=565411,maxLive=777,gcCycles=278737\ninstructions:       32911313\nmax memory:         1018MB\nloaded code:        classes=142,methods=2453\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.52%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.87%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.09%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=148225,visited=137030,backtracked=283759,end=105\nsearch:             maxDepth=1580,constraints=58489\nchoice generators:  thread=97598 (signal=0,lock=4,sharedRef=59235,threadApi=2,reschedule=25129), data=0\nheap:               new=305885,released=632788,maxLive=766,gcCycles=285255\ninstructions:       36238216\nmax memory:         1018MB\nloaded code:        classes=142,methods=2648\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            48.01,
            48.5,
            48.01
        ],
        "llm_output": [
            "```java\nimport java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class QuantumQuokkas {\n    private final List<String> quokkaLabels;\n    \n    public QuantumQuokkas() {\n        this.quokkaLabels = Collections.unmodifiableList(Arrays.asList(\"Zig\", \"Zag\", \"Zog\"));\n    }\n    \n    public boolean isQuokka(String label) {\n        return quokkaLabels.contains(label);\n    }\n    \n    public String getQuokkaLabels() {\n        return quokkaLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        QuantumQuokkas quantumQuokkas = new QuantumQuokkas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Zig' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zig\"));\n            System.out.println(\"Thread 1: Checking if 'Zag' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zag\"));\n            System.out.println(\"Thread 1: Checking if 'Foo' is a Quokka: \" + quantumQuokkas.isQuokka(\"Foo\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Quokka labels: \" + quantumQuokkas.getQuokkaLabels());\n            System.out.println(\"Thread 2: Checking if 'Zog' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zog\"));\n            System.out.println(\"Thread 2: Checking if 'Bar' is a Quokka: \" + quantumQuokkas.isQuokka(\"Bar\"));\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n```",
            "```java\nimport java.util.Collections;\nimport java.util.LinkedHashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class QuantumQuokkas {\n    private final Set<String> quokkaLabels;\n    \n    public QuantumQuokkas() {\n        Set<String> labels = new LinkedHashSet<>();\n        labels.add(\"Zig\");\n        labels.add(\"Zag\");\n        labels.add(\"Zog\");\n        this.quokkaLabels = Collections.unmodifiableSet(labels);\n    }\n    \n    public boolean isQuokka(String label) {\n        return quokkaLabels.contains(label);\n    }\n    \n    public String getQuokkaLabels() {\n        return quokkaLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        QuantumQuokkas quokkas = new QuantumQuokkas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Zig' is a Quokka: \" + quokkas.isQuokka(\"Zig\"));\n            System.out.println(\"Thread 1: Checking if 'Zag' is a Quokka: \" + quokkas.isQuokka(\"Zag\"));\n            System.out.println(\"Thread 1: Checking if 'Foo' is a Quokka: \" + quokkas.isQuokka(\"Foo\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Quokka labels: \" + quokkas.getQuokkaLabels());\n            System.out.println(\"Thread 2: Checking if 'Zog' is a Quokka: \" + quokkas.isQuokka(\"Zog\"));\n            System.out.println(\"Thread 2: Checking if 'Bar' is a Quokka: \" + quokkas.isQuokka(\"Bar\"));\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n```",
            "```java\nimport java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class QuantumQuokkas {\n    private final List<String> quokkaLabels;\n    \n    public QuantumQuokkas() {\n        this.quokkaLabels = Collections.unmodifiableList(Arrays.asList(\"Zig\", \"Zag\", \"Zog\"));\n    }\n    \n    public boolean isQuokka(String label) {\n        return quokkaLabels.contains(label);\n    }\n    \n    public String getQuokkaLabels() {\n        return quokkaLabels.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        QuantumQuokkas quantumQuokkas = new QuantumQuokkas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Zig' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zig\"));\n            System.out.println(\"Thread 1: Checking if 'Zag' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zag\"));\n            System.out.println(\"Thread 1: Checking if 'Foo' is a Quokka: \" + quantumQuokkas.isQuokka(\"Foo\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Quokka labels: \" + quantumQuokkas.getQuokkaLabels());\n            System.out.println(\"Thread 2: Checking if 'Zog' is a Quokka: \" + quantumQuokkas.isQuokka(\"Zog\"));\n            System.out.println(\"Thread 2: Checking if 'Bar' is a Quokka: \" + quantumQuokkas.isQuokka(\"Bar\"));\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Candidate for lock elision. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named SolarSquirrels that represents an immutable collection of the identifiers of the Solar Squirrels: \"Nutty\", \"Whisk\", and \"Fidget\". The class should provide two methods:\n\nA method isSquirrel(String identifier) that returns true if the given identifier is one of the Solar Squirrels, and false otherwise.\nA method getSquirrelIdentifiers() that returns a string representation of a list containing the identifiers of the Solar Squirrels in the order \"Nutty\", \"Whisk\", \"Fidget\".\nEnsure that all fields are properly encapsulated and that the class cannot be modified after construction. Do not make the class thread-unsafe; however, avoid unnecessary synchronization where possible. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.Future;\nimport java.util.concurrent.Callable;\n\npublic class SolarSquirrels {\n    private final List<String> squirrelIdentifiers;\n    \n    public SolarSquirrels() {\n        this.squirrelIdentifiers = Collections.unmodifiableList(\n            Arrays.asList(\"Nutty\", \"Whisk\", \"Fidget\")\n        );\n    }\n    \n    public boolean isSquirrel(String identifier) {\n        return squirrelIdentifiers.contains(identifier);\n    }\n    \n    public String getSquirrelIdentifiers() {\n        return squirrelIdentifiers.toString();\n    }\n    \n    public static void main(String[] args) throws Exception {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        SolarSquirrels solarSquirrels = new SolarSquirrels();\n        \n        Callable<Boolean> checkNutty = () -> {\n            return solarSquirrels.isSquirrel(\"Nutty\");\n        };\n        \n        Callable<Boolean> checkRandom = () -> {\n            return solarSquirrels.isSquirrel(\"Random\");\n        };\n        \n        Runnable printIdentifiers = () -> {\n            System.out.println(solarSquirrels.getSquirrelIdentifiers());\n        };\n        \n        Future<Boolean> nuttyResult = executor.submit(checkNutty);\n        Future<Boolean> randomResult = executor.submit(checkRandom);\n        executor.execute(printIdentifiers);\n        \n        System.out.println(\"Is Nutty a squirrel? \" + nuttyResult.get());\n        System.out.println(\"Is Random a squirrel? \" + randomResult.get());\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.Future;\nimport java.util.concurrent.Callable;\n\npublic class SolarSquirrels {\n    private final List<String> squirrelIdentifiers;\n    \n    public SolarSquirrels() {\n        this.squirrelIdentifiers = Collections.unmodifiableList(\n            Arrays.asList(\"Nutty\", \"Whisk\", \"Fidget\")\n        );\n    }\n    \n    public boolean isSquirrel(String identifier) {\n        return squirrelIdentifiers.contains(identifier);\n    }\n    \n    public String getSquirrelIdentifiers() {\n        return squirrelIdentifiers.toString();\n    }\n    \n    public static void main(String[] args) throws Exception {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        SolarSquirrels solarSquirrels = new SolarSquirrels();\n        \n        Callable<Boolean> task1 = () -> {\n            boolean result = solarSquirrels.isSquirrel(\"Nutty\");\n            System.out.println(\"Thread 1: Is 'Nutty' a squirrel? \" + result);\n            return result;\n        };\n        \n        Callable<Boolean> task2 = () -> {\n            boolean result = solarSquirrels.isSquirrel(\"Rocky\");\n            System.out.println(\"Thread 2: Is 'Rocky' a squirrel? \" + result);\n            return result;\n        };\n        \n        Future<Boolean> future1 = executor.submit(task1);\n        Future<Boolean> future2 = executor.submit(task2);\n        \n        System.out.println(\"Main thread: Squirrel identifiers: \" + solarSquirrels.getSquirrelIdentifiers());\n        \n        Boolean result1 = future1.get();\n        Boolean result2 = future2.get();\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SolarSquirrels {\n    private final List<String> squirrelIdentifiers;\n    \n    public SolarSquirrels() {\n        this.squirrelIdentifiers = Collections.unmodifiableList(\n            Arrays.asList(\"Nutty\", \"Whisk\", \"Fidget\")\n        );\n    }\n    \n    public boolean isSquirrel(String identifier) {\n        return squirrelIdentifiers.contains(identifier);\n    }\n    \n    public String getSquirrelIdentifiers() {\n        return squirrelIdentifiers.toString();\n    }\n    \n    public static void main(String[] args) {\n        SolarSquirrels solarSquirrels = new SolarSquirrels();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Nutty' is a squirrel: \" + \n                solarSquirrels.isSquirrel(\"Nutty\"));\n            System.out.println(\"Thread 1: Checking if 'Rocky' is a squirrel: \" + \n                solarSquirrels.isSquirrel(\"Rocky\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Squirrel identifiers: \" + \n                solarSquirrels.getSquirrelIdentifiers());\n            System.out.println(\"Thread 2: Checking if 'Fidget' is a squirrel: \" + \n                solarSquirrels.isSquirrel(\"Fidget\"));\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            false,
            true,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic final class ThreeStooges {\nprivate static final List<String> STOOGES =\nCollections.unmodifiableList(Arrays.asList(\"Moe\", \"Larry\", \"Curly\"));\nprivate static final Set<String> STOOGES_SET = new HashSet<>(STOOGES);\n\npublic boolean isStooge(String name) {\nreturn STOOGES_SET.contains(name);\n}\n\npublic String getStoogeNames() {\nreturn STOOGES.toString();\n}\n\npublic static void main(String[] args) {\nfinal ThreeStooges stooges = new ThreeStooges();\n\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nString[] namesToCheck = {\"Moe\", \"Shemp\", \"Larry\", \"Curly\", \"John\", \"Curly\", \"Moe\"};\n\nfor (int i = 0; i < namesToCheck.length; i++) {\nfinal int taskId = i;\nfinal String name = namesToCheck[i];\nexecutor.submit(new StoogeCheckerTask(stooges, name, taskId));\n}\n\nexecutor.shutdown();\n}\n}\n\nclass StoogeCheckerTask implements Runnable {\nprivate final ThreeStooges stooges;\nprivate final String name;\nprivate final int taskId;\n\npublic StoogeCheckerTask(ThreeStooges stooges, String name, int taskId) {\nthis.stooges = stooges;\nthis.name = name;\nthis.taskId = taskId;\n}\n\n@Override\npublic void run() {\nSystem.out.println(\"Task ID: \" + taskId + \" - Checking name: \" + name);\nboolean result = stooges.isStooge(name);\nSystem.out.println(\"Task ID: \" + taskId + \" - Is '\" + name + \"' a stooge? \" + result);\n}\n}",
        "max_depth": "158",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 61.20%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 60.21%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.43%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=42727,visited=73036,backtracked=115763,end=253\nsearch:             maxDepth=76,constraints=0\nchoice generators:  thread=42723 (signal=0,lock=4413,sharedRef=26257,threadApi=487,reschedule=5643), data=0\nheap:               new=164559,released=95419,maxLive=754,gcCycles=110418\ninstructions:       9451493\nmax memory:         1009MB\nloaded code:        classes=146,methods=2680\n\n====================================================== search finished",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nSolarSquirrels.main()\n====================================================== search started: 11/16/25 4:21 PM\nIs Nutty a squirrel? true\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "no errors detected",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nSolarSquirrels.main()\n====================================================== search started: 11/16/25 4:21 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            53.26,
            54.42,
            49.66
        ],
        "llm_output": [
            "```java\nimport java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.Future;\nimport java.util.concurrent.Callable;\n\npublic class SolarSquirrels {\n    private final List<String> squirrelIdentifiers;\n    \n    public SolarSquirrels() {\n        this.squirrelIdentifiers = Collections.unmodifiableList(\n            Arrays.asList(\"Nutty\", \"Whisk\", \"Fidget\")\n        );\n    }\n    \n    public boolean isSquirrel(String identifier) {\n        return squirrelIdentifiers.contains(identifier);\n    }\n    \n    public String getSquirrelIdentifiers() {\n        return squirrelIdentifiers.toString();\n    }\n    \n    public static void main(String[] args) throws Exception {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        SolarSquirrels solarSquirrels = new SolarSquirrels();\n        \n        Callable<Boolean> checkNutty = () -> {\n            return solarSquirrels.isSquirrel(\"Nutty\");\n        };\n        \n        Callable<Boolean> checkRandom = () -> {\n            return solarSquirrels.isSquirrel(\"Random\");\n        };\n        \n        Runnable printIdentifiers = () -> {\n            System.out.println(solarSquirrels.getSquirrelIdentifiers());\n        };\n        \n        Future<Boolean> nuttyResult = executor.submit(checkNutty);\n        Future<Boolean> randomResult = executor.submit(checkRandom);\n        executor.execute(printIdentifiers);\n        \n        System.out.println(\"Is Nutty a squirrel? \" + nuttyResult.get());\n        System.out.println(\"Is Random a squirrel? \" + randomResult.get());\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.Future;\nimport java.util.concurrent.Callable;\n\npublic class SolarSquirrels {\n    private final List<String> squirrelIdentifiers;\n    \n    public SolarSquirrels() {\n        this.squirrelIdentifiers = Collections.unmodifiableList(\n            Arrays.asList(\"Nutty\", \"Whisk\", \"Fidget\")\n        );\n    }\n    \n    public boolean isSquirrel(String identifier) {\n        return squirrelIdentifiers.contains(identifier);\n    }\n    \n    public String getSquirrelIdentifiers() {\n        return squirrelIdentifiers.toString();\n    }\n    \n    public static void main(String[] args) throws Exception {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        SolarSquirrels solarSquirrels = new SolarSquirrels();\n        \n        Callable<Boolean> task1 = () -> {\n            boolean result = solarSquirrels.isSquirrel(\"Nutty\");\n            System.out.println(\"Thread 1: Is 'Nutty' a squirrel? \" + result);\n            return result;\n        };\n        \n        Callable<Boolean> task2 = () -> {\n            boolean result = solarSquirrels.isSquirrel(\"Rocky\");\n            System.out.println(\"Thread 2: Is 'Rocky' a squirrel? \" + result);\n            return result;\n        };\n        \n        Future<Boolean> future1 = executor.submit(task1);\n        Future<Boolean> future2 = executor.submit(task2);\n        \n        System.out.println(\"Main thread: Squirrel identifiers: \" + solarSquirrels.getSquirrelIdentifiers());\n        \n        Boolean result1 = future1.get();\n        Boolean result2 = future2.get();\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SolarSquirrels {\n    private final List<String> squirrelIdentifiers;\n    \n    public SolarSquirrels() {\n        this.squirrelIdentifiers = Collections.unmodifiableList(\n            Arrays.asList(\"Nutty\", \"Whisk\", \"Fidget\")\n        );\n    }\n    \n    public boolean isSquirrel(String identifier) {\n        return squirrelIdentifiers.contains(identifier);\n    }\n    \n    public String getSquirrelIdentifiers() {\n        return squirrelIdentifiers.toString();\n    }\n    \n    public static void main(String[] args) {\n        SolarSquirrels solarSquirrels = new SolarSquirrels();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Nutty' is a squirrel: \" + \n                solarSquirrels.isSquirrel(\"Nutty\"));\n            System.out.println(\"Thread 1: Checking if 'Rocky' is a squirrel: \" + \n                solarSquirrels.isSquirrel(\"Rocky\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Squirrel identifiers: \" + \n                solarSquirrels.getSquirrelIdentifiers());\n            System.out.println(\"Thread 2: Checking if 'Fidget' is a squirrel: \" + \n                solarSquirrels.isSquirrel(\"Fidget\"));\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Candidate for lock elision. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named MysticMantas that represents an immutable collection of the tags of the Mystic Mantas: \"Glimmer\", \"Ripple\", and \"Twist\". The class should provide two methods:\n\nA method isManta(String tag) that returns true if the given tag is one of the Mystic Mantas, and false otherwise.\nA method getMantaTags() that returns a string representation of a list containing the tags of the Mystic Mantas in the order \"Glimmer\", \"Ripple\", \"Twist\".\nEnsure that all fields are properly encapsulated and that the class cannot be modified after construction. Do not make the class thread-unsafe; however, avoid unnecessary synchronization where possible. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticMantas {\n    private final List<String> mantaTags;\n    \n    public MysticMantas() {\n        this.mantaTags = Collections.unmodifiableList(Arrays.asList(\"Glimmer\", \"Ripple\", \"Twist\"));\n    }\n    \n    public boolean isManta(String tag) {\n        return mantaTags.contains(tag);\n    }\n    \n    public String getMantaTags() {\n        return mantaTags.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        MysticMantas mantas = new MysticMantas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Glimmer' is a Manta: \" + mantas.isManta(\"Glimmer\"));\n            System.out.println(\"Thread 1: Checking if 'Shadow' is a Manta: \" + mantas.isManta(\"Shadow\"));\n            System.out.println(\"Thread 1: Checking if 'Ripple' is a Manta: \" + mantas.isManta(\"Ripple\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Manta tags: \" + mantas.getMantaTags());\n            System.out.println(\"Thread 2: Checking if 'Twist' is a Manta: \" + mantas.isManta(\"Twist\"));\n            System.out.println(\"Thread 2: Checking if 'Phantom' is a Manta: \" + mantas.isManta(\"Phantom\"));\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticMantas {\n    private final List<String> mantaTags;\n    \n    public MysticMantas() {\n        this.mantaTags = Collections.unmodifiableList(Arrays.asList(\"Glimmer\", \"Ripple\", \"Twist\"));\n    }\n    \n    public boolean isManta(String tag) {\n        return mantaTags.contains(tag);\n    }\n    \n    public String getMantaTags() {\n        return mantaTags.toString();\n    }\n    \n    public static void main(String[] args) {\n        MysticMantas mysticMantas = new MysticMantas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1 - Checking 'Glimmer': \" + mysticMantas.isManta(\"Glimmer\"));\n            System.out.println(\"Thread 1 - Checking 'Shadow': \" + mysticMantas.isManta(\"Shadow\"));\n            System.out.println(\"Thread 1 - Manta tags: \" + mysticMantas.getMantaTags());\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2 - Checking 'Ripple': \" + mysticMantas.isManta(\"Ripple\"));\n            System.out.println(\"Thread 2 - Checking 'Twist': \" + mysticMantas.isManta(\"Twist\"));\n            System.out.println(\"Thread 2 - Manta tags: \" + mysticMantas.getMantaTags());\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticMantas {\n    private final List<String> mantaTags;\n    \n    public MysticMantas() {\n        this.mantaTags = Collections.unmodifiableList(Arrays.asList(\"Glimmer\", \"Ripple\", \"Twist\"));\n    }\n    \n    public boolean isManta(String tag) {\n        return mantaTags.contains(tag);\n    }\n    \n    public String getMantaTags() {\n        return mantaTags.toString();\n    }\n    \n    public static void main(String[] args) {\n        MysticMantas mysticMantas = new MysticMantas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Glimmer' is a Manta: \" + mysticMantas.isManta(\"Glimmer\"));\n            System.out.println(\"Thread 1: Checking if 'Shadow' is a Manta: \" + mysticMantas.isManta(\"Shadow\"));\n            System.out.println(\"Thread 1: Checking if 'Ripple' is a Manta: \" + mysticMantas.isManta(\"Ripple\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Manta tags: \" + mysticMantas.getMantaTags());\n            System.out.println(\"Thread 2: Checking if 'Twist' is a Manta: \" + mysticMantas.isManta(\"Twist\"));\n            System.out.println(\"Thread 2: Checking if 'Phantom' is a Manta: \" + mysticMantas.isManta(\"Phantom\"));\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic final class ThreeStooges {\nprivate static final List<String> STOOGES =\nCollections.unmodifiableList(Arrays.asList(\"Moe\", \"Larry\", \"Curly\"));\nprivate static final Set<String> STOOGES_SET = new HashSet<>(STOOGES);\n\npublic boolean isStooge(String name) {\nreturn STOOGES_SET.contains(name);\n}\n\npublic String getStoogeNames() {\nreturn STOOGES.toString();\n}\n\npublic static void main(String[] args) {\nfinal ThreeStooges stooges = new ThreeStooges();\n\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nString[] namesToCheck = {\"Moe\", \"Shemp\", \"Larry\", \"Curly\", \"John\", \"Curly\", \"Moe\"};\n\nfor (int i = 0; i < namesToCheck.length; i++) {\nfinal int taskId = i;\nfinal String name = namesToCheck[i];\nexecutor.submit(new StoogeCheckerTask(stooges, name, taskId));\n}\n\nexecutor.shutdown();\n}\n}\n\nclass StoogeCheckerTask implements Runnable {\nprivate final ThreeStooges stooges;\nprivate final String name;\nprivate final int taskId;\n\npublic StoogeCheckerTask(ThreeStooges stooges, String name, int taskId) {\nthis.stooges = stooges;\nthis.name = name;\nthis.taskId = taskId;\n}\n\n@Override\npublic void run() {\nSystem.out.println(\"Task ID: \" + taskId + \" - Checking name: \" + name);\nboolean result = stooges.isStooge(name);\nSystem.out.println(\"Task ID: \" + taskId + \" - Is '\" + name + \"' a stooge? \" + result);\n}\n}",
        "max_depth": "158",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.51%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.88%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.09%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=148367,visited=136330,backtracked=283236,end=104\nsearch:             maxDepth=1580,constraints=58898\nchoice generators:  thread=97400 (signal=0,lock=4,sharedRef=59110,threadApi=2,reschedule=24972), data=0\nheap:               new=312194,released=635841,maxLive=766,gcCycles=284697\ninstructions:       36032655\nmax memory:         1018MB\nloaded code:        classes=142,methods=2648\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.36%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.10%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.13%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=147672,visited=135317,backtracked=281511,end=89\nsearch:             maxDepth=1580,constraints=58977\nchoice generators:  thread=96677 (signal=0,lock=4,sharedRef=59797,threadApi=2,reschedule=23597), data=0\nheap:               new=302485,released=635586,maxLive=770,gcCycles=282989\ninstructions:       35661121\nmax memory:         1018MB\nloaded code:        classes=142,methods=2648\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.52%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.87%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.08%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=144708,visited=134745,backtracked=277984,end=103\nsearch:             maxDepth=1580,constraints=56717\nchoice generators:  thread=95632 (signal=0,lock=4,sharedRef=58037,threadApi=2,reschedule=24726), data=0\nheap:               new=308977,released=629770,maxLive=766,gcCycles=279453\ninstructions:       35662048\nmax memory:         1017MB\nloaded code:        classes=142,methods=2648\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            48.01,
            48.56,
            48.01
        ],
        "llm_output": [
            "```java\nimport java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticMantas {\n    private final List<String> mantaTags;\n    \n    public MysticMantas() {\n        this.mantaTags = Collections.unmodifiableList(Arrays.asList(\"Glimmer\", \"Ripple\", \"Twist\"));\n    }\n    \n    public boolean isManta(String tag) {\n        return mantaTags.contains(tag);\n    }\n    \n    public String getMantaTags() {\n        return mantaTags.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        MysticMantas mantas = new MysticMantas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Glimmer' is a Manta: \" + mantas.isManta(\"Glimmer\"));\n            System.out.println(\"Thread 1: Checking if 'Shadow' is a Manta: \" + mantas.isManta(\"Shadow\"));\n            System.out.println(\"Thread 1: Checking if 'Ripple' is a Manta: \" + mantas.isManta(\"Ripple\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Manta tags: \" + mantas.getMantaTags());\n            System.out.println(\"Thread 2: Checking if 'Twist' is a Manta: \" + mantas.isManta(\"Twist\"));\n            System.out.println(\"Thread 2: Checking if 'Phantom' is a Manta: \" + mantas.isManta(\"Phantom\"));\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n```",
            "```java\nimport java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticMantas {\n    private final List<String> mantaTags;\n    \n    public MysticMantas() {\n        this.mantaTags = Collections.unmodifiableList(Arrays.asList(\"Glimmer\", \"Ripple\", \"Twist\"));\n    }\n    \n    public boolean isManta(String tag) {\n        return mantaTags.contains(tag);\n    }\n    \n    public String getMantaTags() {\n        return mantaTags.toString();\n    }\n    \n    public static void main(String[] args) {\n        MysticMantas mysticMantas = new MysticMantas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1 - Checking 'Glimmer': \" + mysticMantas.isManta(\"Glimmer\"));\n            System.out.println(\"Thread 1 - Checking 'Shadow': \" + mysticMantas.isManta(\"Shadow\"));\n            System.out.println(\"Thread 1 - Manta tags: \" + mysticMantas.getMantaTags());\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2 - Checking 'Ripple': \" + mysticMantas.isManta(\"Ripple\"));\n            System.out.println(\"Thread 2 - Checking 'Twist': \" + mysticMantas.isManta(\"Twist\"));\n            System.out.println(\"Thread 2 - Manta tags: \" + mysticMantas.getMantaTags());\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.Arrays;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticMantas {\n    private final List<String> mantaTags;\n    \n    public MysticMantas() {\n        this.mantaTags = Collections.unmodifiableList(Arrays.asList(\"Glimmer\", \"Ripple\", \"Twist\"));\n    }\n    \n    public boolean isManta(String tag) {\n        return mantaTags.contains(tag);\n    }\n    \n    public String getMantaTags() {\n        return mantaTags.toString();\n    }\n    \n    public static void main(String[] args) {\n        MysticMantas mysticMantas = new MysticMantas();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if 'Glimmer' is a Manta: \" + mysticMantas.isManta(\"Glimmer\"));\n            System.out.println(\"Thread 1: Checking if 'Shadow' is a Manta: \" + mysticMantas.isManta(\"Shadow\"));\n            System.out.println(\"Thread 1: Checking if 'Ripple' is a Manta: \" + mysticMantas.isManta(\"Ripple\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Manta tags: \" + mysticMantas.getMantaTags());\n            System.out.println(\"Thread 2: Checking if 'Twist' is a Manta: \" + mysticMantas.isManta(\"Twist\"));\n            System.out.println(\"Thread 2: Checking if 'Phantom' is a Manta: \" + mysticMantas.isManta(\"Phantom\"));\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Avoiding lock-ordering deadlock using try Lock. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that implements a deadlock avoidance mechanism for moving parcels between two lockers. The program should use ReentrantLock to prevent deadlocks when acquiring locks on the source and target lockers. Instead of waiting indefinitely, the implementation should utilize the tryLock() method with a timeout and random pause strategy to attempt acquiring the locks. If both locker locks are successfully acquired, the move should proceed only if the source locker has sufficient items; otherwise, a NotEnoughItemsException is thrown. If the timeout period elapses before both locks can be acquired, the method should return false. The move method should accept parameters for the source locker, target locker, quantity to move, timeout duration, and time unit. Additionally, include nested classes for ParcelCount and Locker, along with the custom exception NotEnoughItemsException. Implement helper methods for calculating fixed and random delay components to be used before retrying the lock acquisition. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.*;\nimport java.util.concurrent.locks.ReentrantLock;\nimport java.util.Random;\n\npublic class ParcelMover {\n    \n    private static final Random random = new Random();\n    \n    static class NotEnoughItemsException extends Exception {\n        public NotEnoughItemsException(String message) {\n            super(message);\n        }\n    }\n    \n    static class ParcelCount {\n        private int count;\n        \n        public ParcelCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void add(int amount) {\n            this.count += amount;\n        }\n        \n        public void subtract(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Locker {\n        private final String name;\n        private final ReentrantLock lock;\n        private final ParcelCount parcelCount;\n        \n        public Locker(String name, int initialCount) {\n            this.name = name;\n            this.lock = new ReentrantLock();\n            this.parcelCount = new ParcelCount(initialCount);\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n        \n        public ParcelCount getParcelCount() {\n            return parcelCount;\n        }\n    }\n    \n    public static boolean move(Locker source, Locker target, int quantity, \n                              long timeout, TimeUnit unit) throws NotEnoughItemsException {\n        long endTime = System.nanoTime() + unit.toNanos(timeout);\n        \n        while (System.nanoTime() < endTime) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = endTime - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = source.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!sourceLocked) {\n                    continue;\n                }\n                \n                remainingTime = endTime - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                targetLocked = target.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!targetLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                if (source.getParcelCount().getCount() < quantity) {\n                    throw new NotEnoughItemsException(\"Source locker does not have enough items\");\n                }\n                \n                source.getParcelCount().subtract(quantity);\n                target.getParcelCount().add(quantity);\n                return true;\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    target.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    source.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    public static void main(String[] args) {\n        Locker locker1 = new Locker(\"Locker1\", 100);\n        Locker locker2 = new Locker(\"Locker2\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> future1 = executor.submit(() -> {\n            try {\n                boolean result = move(locker1, locker2, 30, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 1: Move from Locker1 to Locker2 - \" + result);\n                return result;\n            } catch (NotEnoughItemsException e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n                return false;\n            }\n        });\n        \n        Future<Boolean> future2 = executor.submit(() -> {\n            try {\n                boolean result = move(locker2, locker1, 20, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 2: Move from Locker2 to Locker1 - \" + result);\n                return result;\n            } catch (NotEnoughItemsException e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n                return false;\n            }\n        });\n        \n        try {\n            Boolean result1 = future1.get();\n            Boolean result2 = future2.get();\n            \n            System.out.println(\"Final Locker1 count: \" + locker1.getParcelCount().getCount());\n            System.out.println(\"Final Locker2 count: \" + locker2.getParcelCount().getCount());\n        } catch (InterruptedException | ExecutionException e) {\n            e.printStackTrace();\n        }\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ParcelTransferSystem {\n    \n    private static final Random random = new Random();\n    \n    public static void main(String[] args) {\n        Locker locker1 = new Locker(\"Locker1\", new ParcelCount(100));\n        Locker locker2 = new Locker(\"Locker2\", new ParcelCount(50));\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean result = move(locker1, locker2, 10, 5, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 1: Move from Locker1 to Locker2 - \" + (result ? \"Success\" : \"Failed\"));\n                    Thread.sleep(100);\n                } catch (NotEnoughItemsException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean result = move(locker2, locker1, 5, 5, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 2: Move from Locker2 to Locker1 - \" + (result ? \"Success\" : \"Failed\"));\n                    Thread.sleep(100);\n                } catch (NotEnoughItemsException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(30, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final state - Locker1: \" + locker1.getParcelCount().getCount() + \n                         \", Locker2: \" + locker2.getParcelCount().getCount());\n    }\n    \n    public static boolean move(Locker source, Locker target, int quantity, \n                               long timeout, TimeUnit timeUnit) throws NotEnoughItemsException {\n        long deadline = System.nanoTime() + timeUnit.toNanos(timeout);\n        \n        while (System.nanoTime() < deadline) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = deadline - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = source.getLock().tryLock(remainingTime / 2, TimeUnit.NANOSECONDS);\n                if (sourceLocked) {\n                    remainingTime = deadline - System.nanoTime();\n                    if (remainingTime <= 0) {\n                        return false;\n                    }\n                    \n                    targetLocked = target.getLock().tryLock(remainingTime / 2, TimeUnit.NANOSECONDS);\n                    if (targetLocked) {\n                        if (source.getParcelCount().getCount() < quantity) {\n                            throw new NotEnoughItemsException(\"Not enough items in source locker\");\n                        }\n                        source.getParcelCount().setCount(source.getParcelCount().getCount() - quantity);\n                        target.getParcelCount().setCount(target.getParcelCount().getCount() + quantity);\n                        return true;\n                    }\n                }\n                \n                if (!targetLocked) {\n                    try {\n                        Thread.sleep(getFixedDelay() + getRandomDelay());\n                    } catch (InterruptedException e) {\n                        Thread.currentThread().interrupt();\n                        return false;\n                    }\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    target.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    source.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    static class ParcelCount {\n        private int count;\n        \n        public ParcelCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n    }\n    \n    static class Locker {\n        private final String name;\n        private final ParcelCount parcelCount;\n        private final ReentrantLock lock;\n        \n        public Locker(String name, ParcelCount parcelCount) {\n            this.name = name;\n            this.parcelCount = parcelCount;\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public ParcelCount getParcelCount() {\n            return parcelCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    static class NotEnoughItemsException extends Exception {\n        public NotEnoughItemsException(String message) {\n            super(message);\n        }\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ParcelTransferSystem {\n    \n    private static final Random random = new Random();\n    \n    static class NotEnoughItemsException extends Exception {\n        public NotEnoughItemsException(String message) {\n            super(message);\n        }\n    }\n    \n    static class ParcelCount {\n        private int count;\n        \n        public ParcelCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void add(int amount) {\n            this.count += amount;\n        }\n        \n        public void subtract(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Locker {\n        private final String id;\n        private final ParcelCount parcelCount;\n        private final ReentrantLock lock;\n        \n        public Locker(String id, int initialCount) {\n            this.id = id;\n            this.parcelCount = new ParcelCount(initialCount);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getId() {\n            return id;\n        }\n        \n        public ParcelCount getParcelCount() {\n            return parcelCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    public static boolean move(Locker source, Locker target, int quantity, \n                               long timeout, TimeUnit unit) throws NotEnoughItemsException {\n        long startTime = System.nanoTime();\n        long timeoutNanos = unit.toNanos(timeout);\n        \n        while (System.nanoTime() - startTime < timeoutNanos) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = source.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!sourceLocked) {\n                    return false;\n                }\n                \n                remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                targetLocked = target.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!targetLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                if (source.getParcelCount().getCount() < quantity) {\n                    throw new NotEnoughItemsException(\"Source locker has insufficient items\");\n                }\n                \n                source.getParcelCount().subtract(quantity);\n                target.getParcelCount().add(quantity);\n                return true;\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    target.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    source.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    public static void main(String[] args) {\n        Locker locker1 = new Locker(\"Locker1\", 100);\n        Locker locker2 = new Locker(\"Locker2\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    boolean success = move(locker1, locker2, 10, 1, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 1 - Move \" + (i + 1) + \": \" + \n                                     (success ? \"Success\" : \"Failed\"));\n                    Thread.sleep(100);\n                }\n            } catch (Exception e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    boolean success = move(locker2, locker1, 5, 1, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 2 - Move \" + (i + 1) + \": \" + \n                                     (success ? \"Success\" : \"Failed\"));\n                    Thread.sleep(100);\n                }\n            } catch (Exception e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final state:\");\n        System.out.println(\"Locker1: \" + locker1.getParcelCount().getCount());\n        System.out.println(\"Locker2: \" + locker2.getParcelCount().getCount());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            false
        ],
        "ground_truth": "import java.util.Random;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\nimport static java.util.concurrent.TimeUnit.MILLISECONDS;\nimport static java.util.concurrent.TimeUnit.NANOSECONDS;\n\npublic class LLMC {\nprivate static Random rnd = new Random();\n\npublic boolean transferMoney(Account fromAcct,\nAccount toAcct,\nDollarAmount amount,\nlong timeout,\nTimeUnit unit)\nthrows InsufficientFundsException, InterruptedException {\nlong fixedDelay = getFixedDelayComponentNanos(timeout, unit);\nlong randMod = getRandomDelayModulusNanos(timeout, unit);\nlong timeoutNanos = unit.toNanos(timeout);\nlong startTime = System.nanoTime();\n\nwhile (true) {\nif (fromAcct.lock.tryLock()) {\ntry {\nif (toAcct.lock.tryLock()) {\ntry {\nif (fromAcct.getBalance().compareTo(amount) < 0)\nthrow new InsufficientFundsException();\nelse {\nfromAcct.debit(amount);\ntoAcct.credit(amount);\nSystem.out.println(\"Transfer success: $\" + amount.value + \" from \" + fromAcct.id + \" to \" + toAcct.id);\nreturn true;\n}\n} finally {\ntoAcct.lock.unlock();\n}\n}\n} finally {\nfromAcct.lock.unlock();\n}\n}\n\nif (System.nanoTime() - startTime >= timeoutNanos)\nreturn false;\n\nNANOSECONDS.sleep(fixedDelay + rnd.nextLong() % randMod);\n}\n}\n\nprivate static final long DELAY_FIXED = MILLISECONDS.toNanos(1);\nprivate static final long DELAY_RANDOM = MILLISECONDS.toNanos(10);\n\nstatic long getFixedDelayComponentNanos(long timeout, TimeUnit unit) {\nreturn DELAY_FIXED;\n}\n\nstatic long getRandomDelayModulusNanos(long timeout, TimeUnit unit) {\nreturn DELAY_RANDOM;\n}\n\nstatic class DollarAmount implements Comparable<DollarAmount> {\nfinal int value;\n\nDollarAmount(int dollars) {\nthis.value = dollars;\n}\n\npublic int compareTo(DollarAmount other) {\nreturn Integer.compare(this.value, other.value);\n}\n\npublic String toString() {\nreturn \"$\" + value;\n}\n}\n\nstatic class Account {\nfinal Lock lock = new ReentrantLock();\nprivate DollarAmount balance;\nfinal String id;\n\nAccount(String id, DollarAmount initialBalance) {\nthis.id = id;\nthis.balance = initialBalance;\n}\n\nvoid debit(DollarAmount d) {\nbalance = new DollarAmount(balance.value - d.value);\n}\n\nvoid credit(DollarAmount d) {\nbalance = new DollarAmount(balance.value + d.value);\n}\n\nDollarAmount getBalance() {\nreturn balance;\n}\n}\n\nstatic class InsufficientFundsException extends Exception {\npublic InsufficientFundsException() {\nsuper(\"Insufficient funds for transfer.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nAccount accountA = new Account(\"A\", new DollarAmount(100));\nAccount accountB = new Account(\"B\", new DollarAmount(100));\n\nLLMC dao = new LLMC();\n\nThread t1 = new Thread(() -> {\ntry {\nboolean success = dao.transferMoney(accountA, accountB, new DollarAmount(20), 100, MILLISECONDS);\nSystem.out.println(\"T1: Transfer \" + (success ? \"succeeded\" : \"failed\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nThread t2 = new Thread(() -> {\ntry {\nboolean success = dao.transferMoney(accountB, accountA, new DollarAmount(30), 100, MILLISECONDS);\nSystem.out.println(\"T2: Transfer \" + (success ? \"succeeded\" : \"failed\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final balances:\");\nSystem.out.println(\"Account A: \" + accountA.getBalance());\nSystem.out.println(\"Account B: \" + accountB.getBalance());\nSystem.out.println(\"Total threads including main: 3\");\n}\n}",
        "max_depth": "2792",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 59.12%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 50.27%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 60.93%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=139270,visited=217689,backtracked=356913,end=163\nsearch:             maxDepth=88,constraints=0\nchoice generators:  thread=139268 (signal=0,lock=1095,sharedRef=124954,threadApi=154,reschedule=560), data=0\nheap:               new=308043,released=252073,maxLive=753,gcCycles=347003\ninstructions:       20595531\nmax memory:         1020MB\nloaded code:        classes=143,methods=2466\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 60.33%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 60.33%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=260739,visited=33078,backtracked=265898,end=0\nsearch:             maxDepth=27920,constraints=164511\nchoice generators:  thread=116549 (signal=0,lock=4,sharedRef=54837,threadApi=2,reschedule=0), data=0\nheap:               new=766,released=26,maxLive=740,gcCycles=293817\ninstructions:       12100777\nmax memory:         1015MB\nloaded code:        classes=137,methods=2414\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 57.34%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 57.34%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field ParcelTransferSystem$ParcelCount@20...\"\n\n====================================================== statistics\nstates:             new=178437,visited=21515,backtracked=172032,end=1\nsearch:             maxDepth=27920,constraints=106340\nchoice generators:  thread=85286 (signal=0,lock=4,sharedRef=35509,threadApi=19,reschedule=9), data=0\nheap:               new=1559,released=733,maxLive=751,gcCycles=199952\ninstructions:       8598291\nmax memory:         1001MB\nloaded code:        classes=139,methods=2434\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field ParcelTransferSystem$ParcelCount@20...\""
        ],
        "codebleu_score": [
            55.19,
            55.32,
            55.7
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.ReentrantLock;\nimport java.util.Random;\n\npublic class ParcelMover {\n    \n    private static final Random random = new Random();\n    \n    static class NotEnoughItemsException extends Exception {\n        public NotEnoughItemsException(String message) {\n            super(message);\n        }\n    }\n    \n    static class ParcelCount {\n        private int count;\n        \n        public ParcelCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void add(int amount) {\n            this.count += amount;\n        }\n        \n        public void subtract(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Locker {\n        private final String name;\n        private final ReentrantLock lock;\n        private final ParcelCount parcelCount;\n        \n        public Locker(String name, int initialCount) {\n            this.name = name;\n            this.lock = new ReentrantLock();\n            this.parcelCount = new ParcelCount(initialCount);\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n        \n        public ParcelCount getParcelCount() {\n            return parcelCount;\n        }\n    }\n    \n    public static boolean move(Locker source, Locker target, int quantity, \n                              long timeout, TimeUnit unit) throws NotEnoughItemsException {\n        long endTime = System.nanoTime() + unit.toNanos(timeout);\n        \n        while (System.nanoTime() < endTime) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = endTime - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = source.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!sourceLocked) {\n                    continue;\n                }\n                \n                remainingTime = endTime - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                targetLocked = target.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!targetLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                if (source.getParcelCount().getCount() < quantity) {\n                    throw new NotEnoughItemsException(\"Source locker does not have enough items\");\n                }\n                \n                source.getParcelCount().subtract(quantity);\n                target.getParcelCount().add(quantity);\n                return true;\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    target.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    source.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    public static void main(String[] args) {\n        Locker locker1 = new Locker(\"Locker1\", 100);\n        Locker locker2 = new Locker(\"Locker2\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> future1 = executor.submit(() -> {\n            try {\n                boolean result = move(locker1, locker2, 30, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 1: Move from Locker1 to Locker2 - \" + result);\n                return result;\n            } catch (NotEnoughItemsException e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n                return false;\n            }\n        });\n        \n        Future<Boolean> future2 = executor.submit(() -> {\n            try {\n                boolean result = move(locker2, locker1, 20, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 2: Move from Locker2 to Locker1 - \" + result);\n                return result;\n            } catch (NotEnoughItemsException e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n                return false;\n            }\n        });\n        \n        try {\n            Boolean result1 = future1.get();\n            Boolean result2 = future2.get();\n            \n            System.out.println(\"Final Locker1 count: \" + locker1.getParcelCount().getCount());\n            System.out.println(\"Final Locker2 count: \" + locker2.getParcelCount().getCount());\n        } catch (InterruptedException | ExecutionException e) {\n            e.printStackTrace();\n        }\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ParcelTransferSystem {\n    \n    private static final Random random = new Random();\n    \n    public static void main(String[] args) {\n        Locker locker1 = new Locker(\"Locker1\", new ParcelCount(100));\n        Locker locker2 = new Locker(\"Locker2\", new ParcelCount(50));\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean result = move(locker1, locker2, 10, 5, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 1: Move from Locker1 to Locker2 - \" + (result ? \"Success\" : \"Failed\"));\n                    Thread.sleep(100);\n                } catch (NotEnoughItemsException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean result = move(locker2, locker1, 5, 5, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 2: Move from Locker2 to Locker1 - \" + (result ? \"Success\" : \"Failed\"));\n                    Thread.sleep(100);\n                } catch (NotEnoughItemsException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(30, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final state - Locker1: \" + locker1.getParcelCount().getCount() + \n                         \", Locker2: \" + locker2.getParcelCount().getCount());\n    }\n    \n    public static boolean move(Locker source, Locker target, int quantity, \n                               long timeout, TimeUnit timeUnit) throws NotEnoughItemsException {\n        long deadline = System.nanoTime() + timeUnit.toNanos(timeout);\n        \n        while (System.nanoTime() < deadline) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = deadline - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = source.getLock().tryLock(remainingTime / 2, TimeUnit.NANOSECONDS);\n                if (sourceLocked) {\n                    remainingTime = deadline - System.nanoTime();\n                    if (remainingTime <= 0) {\n                        return false;\n                    }\n                    \n                    targetLocked = target.getLock().tryLock(remainingTime / 2, TimeUnit.NANOSECONDS);\n                    if (targetLocked) {\n                        if (source.getParcelCount().getCount() < quantity) {\n                            throw new NotEnoughItemsException(\"Not enough items in source locker\");\n                        }\n                        source.getParcelCount().setCount(source.getParcelCount().getCount() - quantity);\n                        target.getParcelCount().setCount(target.getParcelCount().getCount() + quantity);\n                        return true;\n                    }\n                }\n                \n                if (!targetLocked) {\n                    try {\n                        Thread.sleep(getFixedDelay() + getRandomDelay());\n                    } catch (InterruptedException e) {\n                        Thread.currentThread().interrupt();\n                        return false;\n                    }\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    target.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    source.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    static class ParcelCount {\n        private int count;\n        \n        public ParcelCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n    }\n    \n    static class Locker {\n        private final String name;\n        private final ParcelCount parcelCount;\n        private final ReentrantLock lock;\n        \n        public Locker(String name, ParcelCount parcelCount) {\n            this.name = name;\n            this.parcelCount = parcelCount;\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public ParcelCount getParcelCount() {\n            return parcelCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    static class NotEnoughItemsException extends Exception {\n        public NotEnoughItemsException(String message) {\n            super(message);\n        }\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ParcelTransferSystem {\n    \n    private static final Random random = new Random();\n    \n    static class NotEnoughItemsException extends Exception {\n        public NotEnoughItemsException(String message) {\n            super(message);\n        }\n    }\n    \n    static class ParcelCount {\n        private int count;\n        \n        public ParcelCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void add(int amount) {\n            this.count += amount;\n        }\n        \n        public void subtract(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Locker {\n        private final String id;\n        private final ParcelCount parcelCount;\n        private final ReentrantLock lock;\n        \n        public Locker(String id, int initialCount) {\n            this.id = id;\n            this.parcelCount = new ParcelCount(initialCount);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getId() {\n            return id;\n        }\n        \n        public ParcelCount getParcelCount() {\n            return parcelCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    public static boolean move(Locker source, Locker target, int quantity, \n                               long timeout, TimeUnit unit) throws NotEnoughItemsException {\n        long startTime = System.nanoTime();\n        long timeoutNanos = unit.toNanos(timeout);\n        \n        while (System.nanoTime() - startTime < timeoutNanos) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = source.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!sourceLocked) {\n                    return false;\n                }\n                \n                remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                targetLocked = target.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!targetLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                if (source.getParcelCount().getCount() < quantity) {\n                    throw new NotEnoughItemsException(\"Source locker has insufficient items\");\n                }\n                \n                source.getParcelCount().subtract(quantity);\n                target.getParcelCount().add(quantity);\n                return true;\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    target.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    source.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    public static void main(String[] args) {\n        Locker locker1 = new Locker(\"Locker1\", 100);\n        Locker locker2 = new Locker(\"Locker2\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    boolean success = move(locker1, locker2, 10, 1, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 1 - Move \" + (i + 1) + \": \" + \n                                     (success ? \"Success\" : \"Failed\"));\n                    Thread.sleep(100);\n                }\n            } catch (Exception e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    boolean success = move(locker2, locker1, 5, 1, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 2 - Move \" + (i + 1) + \": \" + \n                                     (success ? \"Success\" : \"Failed\"));\n                    Thread.sleep(100);\n                }\n            } catch (Exception e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final state:\");\n        System.out.println(\"Locker1: \" + locker1.getParcelCount().getCount());\n        System.out.println(\"Locker2: \" + locker2.getParcelCount().getCount());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Avoiding lock-ordering deadlock using try Lock. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that implements a deadlock avoidance mechanism for swapping items between two containers. The program should use ReentrantLock to prevent deadlocks when acquiring locks on the origin and target containers. Instead of pausing indefinitely, the implementation should utilize the tryLock() method with a timeout and random wait strategy to attempt acquiring the locks. If both container locks are successfully acquired, the swap should proceed only if the origin container has enough elements; otherwise, an InsufficientElementsException is thrown. If the timeout period elapses before both locks can be acquired, the method should return false. The swap method should accept parameters for the origin container, target container, number of elements to swap, timeout duration, and time unit. Additionally, include nested classes for ElementCount and Container, along with the custom exception InsufficientElementsException. Implement helper methods for calculating fixed and random delay components to be used before retrying the lock acquisition. The requirements are as follows:\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.*;\nimport java.util.concurrent.locks.ReentrantLock;\nimport java.util.Random;\nimport java.util.ArrayList;\nimport java.util.List;\n\npublic class DeadlockAvoidanceSwap {\n    \n    private static final Random random = new Random();\n    \n    public static void main(String[] args) throws InterruptedException {\n        Container container1 = new Container(\"Container1\");\n        Container container2 = new Container(\"Container2\");\n        \n        container1.addElements(10);\n        container2.addElements(5);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        CountDownLatch latch = new CountDownLatch(2);\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container1, container2, 3, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 1 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container2, container1, 2, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 2 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        latch.await();\n        \n        System.out.println(\"Final container1 count: \" + container1.getElementCount().getCount());\n        System.out.println(\"Final container2 count: \" + container2.getElementCount().getCount());\n        \n        executor.shutdown();\n    }\n    \n    public static boolean swap(Container origin, Container target, int numberOfElements, \n                               long timeout, TimeUnit unit) throws InsufficientElementsException {\n        long deadline = System.nanoTime() + unit.toNanos(timeout);\n        \n        while (System.nanoTime() < deadline) {\n            boolean originLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = deadline - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                originLocked = origin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                \n                if (originLocked) {\n                    remainingTime = deadline - System.nanoTime();\n                    if (remainingTime <= 0) {\n                        return false;\n                    }\n                    \n                    targetLocked = target.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                    \n                    if (targetLocked) {\n                        if (origin.getElementCount().getCount() < numberOfElements) {\n                            throw new InsufficientElementsException(\n                                \"Origin container has insufficient elements: \" + \n                                origin.getElementCount().getCount() + \" < \" + numberOfElements);\n                        }\n                        \n                        origin.removeElements(numberOfElements);\n                        target.addElements(numberOfElements);\n                        return true;\n                    }\n                }\n                \n                if (!targetLocked) {\n                    try {\n                        Thread.sleep(calculateFixedDelay() + calculateRandomDelay());\n                    } catch (InterruptedException e) {\n                        Thread.currentThread().interrupt();\n                        return false;\n                    }\n                }\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    target.getLock().unlock();\n                }\n                if (originLocked) {\n                    origin.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long calculateFixedDelay() {\n        return 10;\n    }\n    \n    private static long calculateRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    static class ElementCount {\n        private int count;\n        \n        public ElementCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n    }\n    \n    static class Container {\n        private final String name;\n        private final ElementCount elementCount;\n        private final ReentrantLock lock;\n        \n        public Container(String name) {\n            this.name = name;\n            this.elementCount = new ElementCount(0);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public ElementCount getElementCount() {\n            return elementCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n        \n        public void addElements(int count) {\n            elementCount.setCount(elementCount.getCount() + count);\n        }\n        \n        public void removeElements(int count) {\n            elementCount.setCount(elementCount.getCount() - count);\n        }\n    }\n    \n    static class InsufficientElementsException extends Exception {\n        public InsufficientElementsException(String message) {\n            super(message);\n        }\n    }\n}",
            "import java.util.concurrent.*;\nimport java.util.concurrent.locks.ReentrantLock;\nimport java.util.Random;\nimport java.util.ArrayList;\nimport java.util.List;\n\npublic class DeadlockAvoidance {\n    \n    private static final Random random = new Random();\n    \n    public static void main(String[] args) throws InterruptedException {\n        Container container1 = new Container(\"Container1\");\n        Container container2 = new Container(\"Container2\");\n        \n        container1.addElements(10);\n        container2.addElements(5);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container1, container2, 3, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 1 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container2, container1, 2, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 2 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Container1 count: \" + container1.getElementCount().getCount());\n        System.out.println(\"Container2 count: \" + container2.getElementCount().getCount());\n    }\n    \n    public static boolean swap(Container origin, Container target, int numElements, \n                               long timeout, TimeUnit unit) throws InsufficientElementsException {\n        long deadline = System.nanoTime() + unit.toNanos(timeout);\n        \n        while (System.nanoTime() < deadline) {\n            if (origin.getLock().tryLock()) {\n                try {\n                    long remainingTime = deadline - System.nanoTime();\n                    if (remainingTime <= 0) {\n                        return false;\n                    }\n                    \n                    if (target.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS)) {\n                        try {\n                            if (origin.getElementCount().getCount() < numElements) {\n                                throw new InsufficientElementsException(\n                                    \"Origin container has insufficient elements: \" + \n                                    origin.getElementCount().getCount() + \" < \" + numElements);\n                            }\n                            \n                            origin.removeElements(numElements);\n                            target.addElements(numElements);\n                            return true;\n                        } finally {\n                            target.getLock().unlock();\n                        }\n                    }\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    return false;\n                } finally {\n                    origin.getLock().unlock();\n                }\n            }\n            \n            long remainingTime = deadline - System.nanoTime();\n            if (remainingTime <= 0) {\n                return false;\n            }\n            \n            long delay = Math.min(getFixedDelay() + getRandomDelay(), \n                                  TimeUnit.NANOSECONDS.toMillis(remainingTime));\n            if (delay > 0) {\n                try {\n                    Thread.sleep(delay);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    return false;\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    static class ElementCount {\n        private int count;\n        \n        public ElementCount(int initialCount) {\n            this.count = initialCount;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void increment(int amount) {\n            this.count += amount;\n        }\n        \n        public void decrement(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Container {\n        private final String name;\n        private final ElementCount elementCount;\n        private final ReentrantLock lock;\n        \n        public Container(String name) {\n            this.name = name;\n            this.elementCount = new ElementCount(0);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public ElementCount getElementCount() {\n            return elementCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n        \n        public void addElements(int count) {\n            elementCount.increment(count);\n        }\n        \n        public void removeElements(int count) {\n            elementCount.decrement(count);\n        }\n    }\n    \n    static class InsufficientElementsException extends Exception {\n        public InsufficientElementsException(String message) {\n            super(message);\n        }\n    }\n}",
            "import java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\nimport java.util.*;\n\npublic class DeadlockAvoidanceSwap {\n    \n    public static void main(String[] args) throws InterruptedException {\n        Container container1 = new Container(\"Container1\");\n        Container container2 = new Container(\"Container2\");\n        \n        container1.addElements(10);\n        container2.addElements(5);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        CountDownLatch latch = new CountDownLatch(2);\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container1, container2, 3, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 1 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container2, container1, 2, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 2 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        latch.await();\n        \n        System.out.println(\"Container1 count: \" + container1.getCount());\n        System.out.println(\"Container2 count: \" + container2.getCount());\n        \n        executor.shutdown();\n    }\n    \n    public static boolean swap(Container origin, Container target, int numElements, \n                               long timeout, TimeUnit unit) throws InsufficientElementsException {\n        long deadline = System.nanoTime() + unit.toNanos(timeout);\n        Random random = new Random();\n        \n        while (System.nanoTime() < deadline) {\n            long remainingTime = deadline - System.nanoTime();\n            \n            if (origin.lock.tryLock()) {\n                try {\n                    if (target.lock.tryLock()) {\n                        try {\n                            if (origin.elementCount.getCount() < numElements) {\n                                throw new InsufficientElementsException(\n                                    \"Origin container has insufficient elements\");\n                            }\n                            origin.elementCount.decrement(numElements);\n                            target.elementCount.increment(numElements);\n                            return true;\n                        } finally {\n                            target.lock.unlock();\n                        }\n                    }\n                } finally {\n                    origin.lock.unlock();\n                }\n            }\n            \n            if (remainingTime > 0) {\n                try {\n                    long delay = calculateFixedDelay() + calculateRandomDelay(random);\n                    Thread.sleep(Math.min(delay, TimeUnit.NANOSECONDS.toMillis(remainingTime)));\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    return false;\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long calculateFixedDelay() {\n        return 10;\n    }\n    \n    private static long calculateRandomDelay(Random random) {\n        return random.nextInt(50);\n    }\n    \n    static class ElementCount {\n        private int count;\n        \n        public ElementCount(int initialCount) {\n            this.count = initialCount;\n        }\n        \n        public synchronized int getCount() {\n            return count;\n        }\n        \n        public synchronized void increment(int amount) {\n            count += amount;\n        }\n        \n        public synchronized void decrement(int amount) {\n            count -= amount;\n        }\n    }\n    \n    static class Container {\n        private final String name;\n        private final ElementCount elementCount;\n        private final ReentrantLock lock;\n        \n        public Container(String name) {\n            this.name = name;\n            this.elementCount = new ElementCount(0);\n            this.lock = new ReentrantLock();\n        }\n        \n        public void addElements(int count) {\n            elementCount.increment(count);\n        }\n        \n        public int getCount() {\n            return elementCount.getCount();\n        }\n        \n        public String getName() {\n            return name;\n        }\n    }\n    \n    static class InsufficientElementsException extends Exception {\n        public InsufficientElementsException(String message) {\n            super(message);\n        }\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.Random;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\nimport static java.util.concurrent.TimeUnit.MILLISECONDS;\nimport static java.util.concurrent.TimeUnit.NANOSECONDS;\n\npublic class LLMC {\nprivate static Random rnd = new Random();\n\npublic boolean transferMoney(Account fromAcct,\nAccount toAcct,\nDollarAmount amount,\nlong timeout,\nTimeUnit unit)\nthrows InsufficientFundsException, InterruptedException {\nlong fixedDelay = getFixedDelayComponentNanos(timeout, unit);\nlong randMod = getRandomDelayModulusNanos(timeout, unit);\nlong timeoutNanos = unit.toNanos(timeout);\nlong startTime = System.nanoTime();\n\nwhile (true) {\nif (fromAcct.lock.tryLock()) {\ntry {\nif (toAcct.lock.tryLock()) {\ntry {\nif (fromAcct.getBalance().compareTo(amount) < 0)\nthrow new InsufficientFundsException();\nelse {\nfromAcct.debit(amount);\ntoAcct.credit(amount);\nSystem.out.println(\"Transfer success: $\" + amount.value + \" from \" + fromAcct.id + \" to \" + toAcct.id);\nreturn true;\n}\n} finally {\ntoAcct.lock.unlock();\n}\n}\n} finally {\nfromAcct.lock.unlock();\n}\n}\n\nif (System.nanoTime() - startTime >= timeoutNanos)\nreturn false;\n\nNANOSECONDS.sleep(fixedDelay + rnd.nextLong() % randMod);\n}\n}\n\nprivate static final long DELAY_FIXED = MILLISECONDS.toNanos(1);\nprivate static final long DELAY_RANDOM = MILLISECONDS.toNanos(10);\n\nstatic long getFixedDelayComponentNanos(long timeout, TimeUnit unit) {\nreturn DELAY_FIXED;\n}\n\nstatic long getRandomDelayModulusNanos(long timeout, TimeUnit unit) {\nreturn DELAY_RANDOM;\n}\n\nstatic class DollarAmount implements Comparable<DollarAmount> {\nfinal int value;\n\nDollarAmount(int dollars) {\nthis.value = dollars;\n}\n\npublic int compareTo(DollarAmount other) {\nreturn Integer.compare(this.value, other.value);\n}\n\npublic String toString() {\nreturn \"$\" + value;\n}\n}\n\nstatic class Account {\nfinal Lock lock = new ReentrantLock();\nprivate DollarAmount balance;\nfinal String id;\n\nAccount(String id, DollarAmount initialBalance) {\nthis.id = id;\nthis.balance = initialBalance;\n}\n\nvoid debit(DollarAmount d) {\nbalance = new DollarAmount(balance.value - d.value);\n}\n\nvoid credit(DollarAmount d) {\nbalance = new DollarAmount(balance.value + d.value);\n}\n\nDollarAmount getBalance() {\nreturn balance;\n}\n}\n\nstatic class InsufficientFundsException extends Exception {\npublic InsufficientFundsException() {\nsuper(\"Insufficient funds for transfer.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nAccount accountA = new Account(\"A\", new DollarAmount(100));\nAccount accountB = new Account(\"B\", new DollarAmount(100));\n\nLLMC dao = new LLMC();\n\nThread t1 = new Thread(() -> {\ntry {\nboolean success = dao.transferMoney(accountA, accountB, new DollarAmount(20), 100, MILLISECONDS);\nSystem.out.println(\"T1: Transfer \" + (success ? \"succeeded\" : \"failed\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nThread t2 = new Thread(() -> {\ntry {\nboolean success = dao.transferMoney(accountB, accountA, new DollarAmount(30), 100, MILLISECONDS);\nSystem.out.println(\"T2: Transfer \" + (success ? \"succeeded\" : \"failed\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final balances:\");\nSystem.out.println(\"Account A: \" + accountA.getBalance());\nSystem.out.println(\"Account B: \" + accountB.getBalance());\nSystem.out.println(\"Total threads including main: 3\");\n}\n}",
        "max_depth": "2792",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nDeadlockAvoidanceSwap.main()\n====================================================== search started: 11/16/25 4:23 PM\njava.lang.ArrayIndexOutOfBoundsException: 5\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nDeadlockAvoidance.main()\n====================================================== search started: 11/16/25 4:24 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nDeadlockAvoidanceSwap.main()\n====================================================== search started: 11/16/25 4:24 PM\njava.lang.ArrayIndexOutOfBoundsException: 5\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            51.99,
            51.95,
            49.21
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.ReentrantLock;\nimport java.util.Random;\nimport java.util.ArrayList;\nimport java.util.List;\n\npublic class DeadlockAvoidanceSwap {\n    \n    private static final Random random = new Random();\n    \n    public static void main(String[] args) throws InterruptedException {\n        Container container1 = new Container(\"Container1\");\n        Container container2 = new Container(\"Container2\");\n        \n        container1.addElements(10);\n        container2.addElements(5);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        CountDownLatch latch = new CountDownLatch(2);\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container1, container2, 3, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 1 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container2, container1, 2, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 2 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        latch.await();\n        \n        System.out.println(\"Final container1 count: \" + container1.getElementCount().getCount());\n        System.out.println(\"Final container2 count: \" + container2.getElementCount().getCount());\n        \n        executor.shutdown();\n    }\n    \n    public static boolean swap(Container origin, Container target, int numberOfElements, \n                               long timeout, TimeUnit unit) throws InsufficientElementsException {\n        long deadline = System.nanoTime() + unit.toNanos(timeout);\n        \n        while (System.nanoTime() < deadline) {\n            boolean originLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = deadline - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                originLocked = origin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                \n                if (originLocked) {\n                    remainingTime = deadline - System.nanoTime();\n                    if (remainingTime <= 0) {\n                        return false;\n                    }\n                    \n                    targetLocked = target.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                    \n                    if (targetLocked) {\n                        if (origin.getElementCount().getCount() < numberOfElements) {\n                            throw new InsufficientElementsException(\n                                \"Origin container has insufficient elements: \" + \n                                origin.getElementCount().getCount() + \" < \" + numberOfElements);\n                        }\n                        \n                        origin.removeElements(numberOfElements);\n                        target.addElements(numberOfElements);\n                        return true;\n                    }\n                }\n                \n                if (!targetLocked) {\n                    try {\n                        Thread.sleep(calculateFixedDelay() + calculateRandomDelay());\n                    } catch (InterruptedException e) {\n                        Thread.currentThread().interrupt();\n                        return false;\n                    }\n                }\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    target.getLock().unlock();\n                }\n                if (originLocked) {\n                    origin.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long calculateFixedDelay() {\n        return 10;\n    }\n    \n    private static long calculateRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    static class ElementCount {\n        private int count;\n        \n        public ElementCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n    }\n    \n    static class Container {\n        private final String name;\n        private final ElementCount elementCount;\n        private final ReentrantLock lock;\n        \n        public Container(String name) {\n            this.name = name;\n            this.elementCount = new ElementCount(0);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public ElementCount getElementCount() {\n            return elementCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n        \n        public void addElements(int count) {\n            elementCount.setCount(elementCount.getCount() + count);\n        }\n        \n        public void removeElements(int count) {\n            elementCount.setCount(elementCount.getCount() - count);\n        }\n    }\n    \n    static class InsufficientElementsException extends Exception {\n        public InsufficientElementsException(String message) {\n            super(message);\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.ReentrantLock;\nimport java.util.Random;\nimport java.util.ArrayList;\nimport java.util.List;\n\npublic class DeadlockAvoidance {\n    \n    private static final Random random = new Random();\n    \n    public static void main(String[] args) throws InterruptedException {\n        Container container1 = new Container(\"Container1\");\n        Container container2 = new Container(\"Container2\");\n        \n        container1.addElements(10);\n        container2.addElements(5);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container1, container2, 3, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 1 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container2, container1, 2, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 2 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Container1 count: \" + container1.getElementCount().getCount());\n        System.out.println(\"Container2 count: \" + container2.getElementCount().getCount());\n    }\n    \n    public static boolean swap(Container origin, Container target, int numElements, \n                               long timeout, TimeUnit unit) throws InsufficientElementsException {\n        long deadline = System.nanoTime() + unit.toNanos(timeout);\n        \n        while (System.nanoTime() < deadline) {\n            if (origin.getLock().tryLock()) {\n                try {\n                    long remainingTime = deadline - System.nanoTime();\n                    if (remainingTime <= 0) {\n                        return false;\n                    }\n                    \n                    if (target.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS)) {\n                        try {\n                            if (origin.getElementCount().getCount() < numElements) {\n                                throw new InsufficientElementsException(\n                                    \"Origin container has insufficient elements: \" + \n                                    origin.getElementCount().getCount() + \" < \" + numElements);\n                            }\n                            \n                            origin.removeElements(numElements);\n                            target.addElements(numElements);\n                            return true;\n                        } finally {\n                            target.getLock().unlock();\n                        }\n                    }\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    return false;\n                } finally {\n                    origin.getLock().unlock();\n                }\n            }\n            \n            long remainingTime = deadline - System.nanoTime();\n            if (remainingTime <= 0) {\n                return false;\n            }\n            \n            long delay = Math.min(getFixedDelay() + getRandomDelay(), \n                                  TimeUnit.NANOSECONDS.toMillis(remainingTime));\n            if (delay > 0) {\n                try {\n                    Thread.sleep(delay);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    return false;\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    static class ElementCount {\n        private int count;\n        \n        public ElementCount(int initialCount) {\n            this.count = initialCount;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void increment(int amount) {\n            this.count += amount;\n        }\n        \n        public void decrement(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Container {\n        private final String name;\n        private final ElementCount elementCount;\n        private final ReentrantLock lock;\n        \n        public Container(String name) {\n            this.name = name;\n            this.elementCount = new ElementCount(0);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public ElementCount getElementCount() {\n            return elementCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n        \n        public void addElements(int count) {\n            elementCount.increment(count);\n        }\n        \n        public void removeElements(int count) {\n            elementCount.decrement(count);\n        }\n    }\n    \n    static class InsufficientElementsException extends Exception {\n        public InsufficientElementsException(String message) {\n            super(message);\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\nimport java.util.*;\n\npublic class DeadlockAvoidanceSwap {\n    \n    public static void main(String[] args) throws InterruptedException {\n        Container container1 = new Container(\"Container1\");\n        Container container2 = new Container(\"Container2\");\n        \n        container1.addElements(10);\n        container2.addElements(5);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        CountDownLatch latch = new CountDownLatch(2);\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container1, container2, 3, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 1 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                boolean result = swap(container2, container1, 2, 5, TimeUnit.SECONDS);\n                System.out.println(\"Thread 2 swap result: \" + result);\n            } catch (InsufficientElementsException e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        latch.await();\n        \n        System.out.println(\"Container1 count: \" + container1.getCount());\n        System.out.println(\"Container2 count: \" + container2.getCount());\n        \n        executor.shutdown();\n    }\n    \n    public static boolean swap(Container origin, Container target, int numElements, \n                               long timeout, TimeUnit unit) throws InsufficientElementsException {\n        long deadline = System.nanoTime() + unit.toNanos(timeout);\n        Random random = new Random();\n        \n        while (System.nanoTime() < deadline) {\n            long remainingTime = deadline - System.nanoTime();\n            \n            if (origin.lock.tryLock()) {\n                try {\n                    if (target.lock.tryLock()) {\n                        try {\n                            if (origin.elementCount.getCount() < numElements) {\n                                throw new InsufficientElementsException(\n                                    \"Origin container has insufficient elements\");\n                            }\n                            origin.elementCount.decrement(numElements);\n                            target.elementCount.increment(numElements);\n                            return true;\n                        } finally {\n                            target.lock.unlock();\n                        }\n                    }\n                } finally {\n                    origin.lock.unlock();\n                }\n            }\n            \n            if (remainingTime > 0) {\n                try {\n                    long delay = calculateFixedDelay() + calculateRandomDelay(random);\n                    Thread.sleep(Math.min(delay, TimeUnit.NANOSECONDS.toMillis(remainingTime)));\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    return false;\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long calculateFixedDelay() {\n        return 10;\n    }\n    \n    private static long calculateRandomDelay(Random random) {\n        return random.nextInt(50);\n    }\n    \n    static class ElementCount {\n        private int count;\n        \n        public ElementCount(int initialCount) {\n            this.count = initialCount;\n        }\n        \n        public synchronized int getCount() {\n            return count;\n        }\n        \n        public synchronized void increment(int amount) {\n            count += amount;\n        }\n        \n        public synchronized void decrement(int amount) {\n            count -= amount;\n        }\n    }\n    \n    static class Container {\n        private final String name;\n        private final ElementCount elementCount;\n        private final ReentrantLock lock;\n        \n        public Container(String name) {\n            this.name = name;\n            this.elementCount = new ElementCount(0);\n            this.lock = new ReentrantLock();\n        }\n        \n        public void addElements(int count) {\n            elementCount.increment(count);\n        }\n        \n        public int getCount() {\n            return elementCount.getCount();\n        }\n        \n        public String getName() {\n            return name;\n        }\n    }\n    \n    static class InsufficientElementsException extends Exception {\n        public InsufficientElementsException(String message) {\n            super(message);\n        }\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Avoiding lock-ordering deadlock using try Lock. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that implements a deadlock avoidance mechanism for moving widgets between two bins. The program should use ReentrantLock to prevent deadlocks when acquiring locks on the source and target bins. Instead of waiting endlessly, the implementation should utilize the tryLock() method with a timeout and random pause pattern to attempt acquiring the locks. If both bin locks are successfully acquired, the move should proceed only if the source bin contains enough widgets; otherwise, a NotEnoughWidgetsException is thrown. If the timeout period elapses before both locks can be acquired, the method should return false. The move method should accept parameters for the source bin, target bin, number of widgets to move, timeout duration, and time unit. Additionally, include nested classes for WidgetCount and Bin, along with the custom exception NotEnoughWidgetsException. Implement helper methods for calculating fixed and random delay components to be used before retrying the lock acquisition. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.",
        "code_list": [
            "import java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class WidgetTransfer {\n    \n    private static final Random random = new Random();\n    \n    public static void main(String[] args) {\n        Bin bin1 = new Bin(\"Bin1\", 100);\n        Bin bin2 = new Bin(\"Bin2\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(bin1, bin2, 10, 2, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 1 - Move from Bin1 to Bin2: \" + success);\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 1 - Not enough widgets: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(bin2, bin1, 5, 2, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 2 - Move from Bin2 to Bin1: \" + success);\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 2 - Not enough widgets: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final state - Bin1: \" + bin1.getWidgetCount().getCount());\n        System.out.println(\"Final state - Bin2: \" + bin2.getWidgetCount().getCount());\n    }\n    \n    public static boolean move(Bin sourceBin, Bin targetBin, int widgets, long timeout, TimeUnit timeUnit) \n            throws NotEnoughWidgetsException {\n        long startTime = System.nanoTime();\n        long timeoutNanos = timeUnit.toNanos(timeout);\n        \n        while (System.nanoTime() - startTime < timeoutNanos) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = sourceBin.getLock().tryLock(remainingTime / 2, TimeUnit.NANOSECONDS);\n                if (!sourceLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                targetLocked = targetBin.getLock().tryLock(remainingTime / 2, TimeUnit.NANOSECONDS);\n                if (!targetLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                if (sourceBin.getWidgetCount().getCount() < widgets) {\n                    throw new NotEnoughWidgetsException(\"Source bin has only \" + \n                        sourceBin.getWidgetCount().getCount() + \" widgets, but \" + widgets + \" requested\");\n                }\n                \n                sourceBin.getWidgetCount().setCount(sourceBin.getWidgetCount().getCount() - widgets);\n                targetBin.getWidgetCount().setCount(targetBin.getWidgetCount().getCount() + widgets);\n                \n                return true;\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    targetBin.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    sourceBin.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    static class WidgetCount {\n        private int count;\n        \n        public WidgetCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n    }\n    \n    static class Bin {\n        private final String name;\n        private final WidgetCount widgetCount;\n        private final ReentrantLock lock;\n        \n        public Bin(String name, int initialCount) {\n            this.name = name;\n            this.widgetCount = new WidgetCount(initialCount);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public WidgetCount getWidgetCount() {\n            return widgetCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    static class NotEnoughWidgetsException extends Exception {\n        public NotEnoughWidgetsException(String message) {\n            super(message);\n        }\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class WidgetTransferSystem {\n    \n    private static final Random random = new Random();\n    \n    static class NotEnoughWidgetsException extends Exception {\n        public NotEnoughWidgetsException(String message) {\n            super(message);\n        }\n    }\n    \n    static class WidgetCount {\n        private int count;\n        \n        public WidgetCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void add(int amount) {\n            this.count += amount;\n        }\n        \n        public void subtract(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Bin {\n        private final String name;\n        private final WidgetCount widgetCount;\n        private final ReentrantLock lock;\n        \n        public Bin(String name, int initialCount) {\n            this.name = name;\n            this.widgetCount = new WidgetCount(initialCount);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public WidgetCount getWidgetCount() {\n            return widgetCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    public static boolean move(Bin sourceBin, Bin targetBin, int widgetsToMove, \n                               long timeout, TimeUnit timeUnit) throws NotEnoughWidgetsException {\n        long deadline = System.nanoTime() + timeUnit.toNanos(timeout);\n        \n        while (System.nanoTime() < deadline) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = deadline - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = sourceBin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                \n                if (sourceLocked) {\n                    remainingTime = deadline - System.nanoTime();\n                    if (remainingTime <= 0) {\n                        return false;\n                    }\n                    \n                    targetLocked = targetBin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                    \n                    if (targetLocked) {\n                        if (sourceBin.getWidgetCount().getCount() >= widgetsToMove) {\n                            sourceBin.getWidgetCount().subtract(widgetsToMove);\n                            targetBin.getWidgetCount().add(widgetsToMove);\n                            return true;\n                        } else {\n                            throw new NotEnoughWidgetsException(\n                                \"Source bin \" + sourceBin.getName() + \" has only \" + \n                                sourceBin.getWidgetCount().getCount() + \" widgets, but \" + \n                                widgetsToMove + \" were requested\");\n                        }\n                    }\n                }\n                \n                if (!targetLocked && System.nanoTime() < deadline) {\n                    try {\n                        Thread.sleep(calculateFixedDelay() + calculateRandomDelay());\n                    } catch (InterruptedException e) {\n                        Thread.currentThread().interrupt();\n                        return false;\n                    }\n                }\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    targetBin.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    sourceBin.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long calculateFixedDelay() {\n        return 10;\n    }\n    \n    private static long calculateRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    public static void main(String[] args) {\n        Bin binA = new Bin(\"BinA\", 100);\n        Bin binB = new Bin(\"BinB\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(binA, binB, 10, 2, TimeUnit.SECONDS);\n                    if (success) {\n                        System.out.println(\"Thread 1: Moved 10 widgets from BinA to BinB\");\n                    } else {\n                        System.out.println(\"Thread 1: Failed to acquire locks in time\");\n                    }\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(binB, binA, 5, 2, TimeUnit.SECONDS);\n                    if (success) {\n                        System.out.println(\"Thread 2: Moved 5 widgets from BinB to BinA\");\n                    } else {\n                        System.out.println(\"Thread 2: Failed to acquire locks in time\");\n                    }\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"Final BinA count: \" + binA.getWidgetCount().getCount());\n        System.out.println(\"Final BinB count: \" + binB.getWidgetCount().getCount());\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class WidgetTransferSystem {\n    \n    private static final Random random = new Random();\n    \n    static class NotEnoughWidgetsException extends Exception {\n        public NotEnoughWidgetsException(String message) {\n            super(message);\n        }\n    }\n    \n    static class WidgetCount {\n        private int count;\n        \n        public WidgetCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void add(int amount) {\n            this.count += amount;\n        }\n        \n        public void subtract(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Bin {\n        private final String name;\n        private final WidgetCount widgetCount;\n        private final ReentrantLock lock;\n        \n        public Bin(String name, int initialCount) {\n            this.name = name;\n            this.widgetCount = new WidgetCount(initialCount);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public WidgetCount getWidgetCount() {\n            return widgetCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    public static boolean move(Bin sourceBin, Bin targetBin, int numberOfWidgets, \n                               long timeout, TimeUnit timeUnit) throws NotEnoughWidgetsException {\n        long startTime = System.nanoTime();\n        long timeoutNanos = timeUnit.toNanos(timeout);\n        \n        while (System.nanoTime() - startTime < timeoutNanos) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = sourceBin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!sourceLocked) {\n                    return false;\n                }\n                \n                remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                targetLocked = targetBin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!targetLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                if (sourceBin.getWidgetCount().getCount() < numberOfWidgets) {\n                    throw new NotEnoughWidgetsException(\"Source bin does not have enough widgets\");\n                }\n                \n                sourceBin.getWidgetCount().subtract(numberOfWidgets);\n                targetBin.getWidgetCount().add(numberOfWidgets);\n                \n                return true;\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    targetBin.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    sourceBin.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    public static void main(String[] args) {\n        Bin bin1 = new Bin(\"Bin1\", 100);\n        Bin bin2 = new Bin(\"Bin2\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(bin1, bin2, 10, 1, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 1 - Move \" + (i + 1) + \": \" + \n                        (success ? \"Success\" : \"Failed\") + \n                        \" | Bin1: \" + bin1.getWidgetCount().getCount() + \n                        \", Bin2: \" + bin2.getWidgetCount().getCount());\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 1 - Move \" + (i + 1) + \": \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(bin2, bin1, 5, 1, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 2 - Move \" + (i + 1) + \": \" + \n                        (success ? \"Success\" : \"Failed\") + \n                        \" | Bin1: \" + bin1.getWidgetCount().getCount() + \n                        \", Bin2: \" + bin2.getWidgetCount().getCount());\n                    Thread.sleep(150);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 2 - Move \" + (i + 1) + \": \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final state - Bin1: \" + bin1.getWidgetCount().getCount() + \n                          \", Bin2: \" + bin2.getWidgetCount().getCount());\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.Random;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\nimport static java.util.concurrent.TimeUnit.MILLISECONDS;\nimport static java.util.concurrent.TimeUnit.NANOSECONDS;\n\npublic class LLMC {\nprivate static Random rnd = new Random();\n\npublic boolean transferMoney(Account fromAcct,\nAccount toAcct,\nDollarAmount amount,\nlong timeout,\nTimeUnit unit)\nthrows InsufficientFundsException, InterruptedException {\nlong fixedDelay = getFixedDelayComponentNanos(timeout, unit);\nlong randMod = getRandomDelayModulusNanos(timeout, unit);\nlong timeoutNanos = unit.toNanos(timeout);\nlong startTime = System.nanoTime();\n\nwhile (true) {\nif (fromAcct.lock.tryLock()) {\ntry {\nif (toAcct.lock.tryLock()) {\ntry {\nif (fromAcct.getBalance().compareTo(amount) < 0)\nthrow new InsufficientFundsException();\nelse {\nfromAcct.debit(amount);\ntoAcct.credit(amount);\nSystem.out.println(\"Transfer success: $\" + amount.value + \" from \" + fromAcct.id + \" to \" + toAcct.id);\nreturn true;\n}\n} finally {\ntoAcct.lock.unlock();\n}\n}\n} finally {\nfromAcct.lock.unlock();\n}\n}\n\nif (System.nanoTime() - startTime >= timeoutNanos)\nreturn false;\n\nNANOSECONDS.sleep(fixedDelay + rnd.nextLong() % randMod);\n}\n}\n\nprivate static final long DELAY_FIXED = MILLISECONDS.toNanos(1);\nprivate static final long DELAY_RANDOM = MILLISECONDS.toNanos(10);\n\nstatic long getFixedDelayComponentNanos(long timeout, TimeUnit unit) {\nreturn DELAY_FIXED;\n}\n\nstatic long getRandomDelayModulusNanos(long timeout, TimeUnit unit) {\nreturn DELAY_RANDOM;\n}\n\nstatic class DollarAmount implements Comparable<DollarAmount> {\nfinal int value;\n\nDollarAmount(int dollars) {\nthis.value = dollars;\n}\n\npublic int compareTo(DollarAmount other) {\nreturn Integer.compare(this.value, other.value);\n}\n\npublic String toString() {\nreturn \"$\" + value;\n}\n}\n\nstatic class Account {\nfinal Lock lock = new ReentrantLock();\nprivate DollarAmount balance;\nfinal String id;\n\nAccount(String id, DollarAmount initialBalance) {\nthis.id = id;\nthis.balance = initialBalance;\n}\n\nvoid debit(DollarAmount d) {\nbalance = new DollarAmount(balance.value - d.value);\n}\n\nvoid credit(DollarAmount d) {\nbalance = new DollarAmount(balance.value + d.value);\n}\n\nDollarAmount getBalance() {\nreturn balance;\n}\n}\n\nstatic class InsufficientFundsException extends Exception {\npublic InsufficientFundsException() {\nsuper(\"Insufficient funds for transfer.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nAccount accountA = new Account(\"A\", new DollarAmount(100));\nAccount accountB = new Account(\"B\", new DollarAmount(100));\n\nLLMC dao = new LLMC();\n\nThread t1 = new Thread(() -> {\ntry {\nboolean success = dao.transferMoney(accountA, accountB, new DollarAmount(20), 100, MILLISECONDS);\nSystem.out.println(\"T1: Transfer \" + (success ? \"succeeded\" : \"failed\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nThread t2 = new Thread(() -> {\ntry {\nboolean success = dao.transferMoney(accountB, accountA, new DollarAmount(30), 100, MILLISECONDS);\nSystem.out.println(\"T2: Transfer \" + (success ? \"succeeded\" : \"failed\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final balances:\");\nSystem.out.println(\"Account A: \" + accountA.getBalance());\nSystem.out.println(\"Account B: \" + accountB.getBalance());\nSystem.out.println(\"Total threads including main: 3\");\n}\n}",
        "max_depth": "2792",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 57.31%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 57.31%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field WidgetTransfer$WidgetCount@203.coun...\"\n\n====================================================== statistics\nstates:             new=177830,visited=21436,backtracked=171346,end=1\nsearch:             maxDepth=27920,constraints=105913\nchoice generators:  thread=85057 (signal=0,lock=4,sharedRef=35367,threadApi=21,reschedule=9), data=0\nheap:               new=1457,released=740,maxLive=746,gcCycles=199266\ninstructions:       8580088\nmax memory:         1001MB\nloaded code:        classes=139,methods=2432\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.36%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 57.36%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 57.36%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field WidgetTransferSystem$WidgetCount@1d...\"\n\n====================================================== statistics\nstates:             new=177985,visited=22373,backtracked=172438,end=1\nsearch:             maxDepth=27920,constraints=105970\nchoice generators:  thread=85422 (signal=0,lock=34,sharedRef=35810,threadApi=41,reschedule=15), data=0\nheap:               new=5196,released=2009,maxLive=765,gcCycles=200358\ninstructions:       8998119\nmax memory:         1001MB\nloaded code:        classes=144,methods=2517\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 57.16%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 57.16%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field WidgetTransferSystem$WidgetCount@20...\"\n\n====================================================== statistics\nstates:             new=175155,visited=21072,backtracked=168307,end=1\nsearch:             maxDepth=27920,constraints=104022\nchoice generators:  thread=84044 (signal=0,lock=4,sharedRef=34742,threadApi=21,reschedule=11), data=0\nheap:               new=1535,released=756,maxLive=753,gcCycles=196227\ninstructions:       8466090\nmax memory:         1001MB\nloaded code:        classes=139,methods=2434\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field WidgetTransfer$WidgetCount@203.coun...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field WidgetTransferSystem$WidgetCount@1d...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field WidgetTransferSystem$WidgetCount@20...\""
        ],
        "codebleu_score": [
            52.51,
            56.17,
            55.22
        ],
        "llm_output": [
            "```java\nimport java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class WidgetTransfer {\n    \n    private static final Random random = new Random();\n    \n    public static void main(String[] args) {\n        Bin bin1 = new Bin(\"Bin1\", 100);\n        Bin bin2 = new Bin(\"Bin2\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(bin1, bin2, 10, 2, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 1 - Move from Bin1 to Bin2: \" + success);\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 1 - Not enough widgets: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(bin2, bin1, 5, 2, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 2 - Move from Bin2 to Bin1: \" + success);\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 2 - Not enough widgets: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final state - Bin1: \" + bin1.getWidgetCount().getCount());\n        System.out.println(\"Final state - Bin2: \" + bin2.getWidgetCount().getCount());\n    }\n    \n    public static boolean move(Bin sourceBin, Bin targetBin, int widgets, long timeout, TimeUnit timeUnit) \n            throws NotEnoughWidgetsException {\n        long startTime = System.nanoTime();\n        long timeoutNanos = timeUnit.toNanos(timeout);\n        \n        while (System.nanoTime() - startTime < timeoutNanos) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = sourceBin.getLock().tryLock(remainingTime / 2, TimeUnit.NANOSECONDS);\n                if (!sourceLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                targetLocked = targetBin.getLock().tryLock(remainingTime / 2, TimeUnit.NANOSECONDS);\n                if (!targetLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                if (sourceBin.getWidgetCount().getCount() < widgets) {\n                    throw new NotEnoughWidgetsException(\"Source bin has only \" + \n                        sourceBin.getWidgetCount().getCount() + \" widgets, but \" + widgets + \" requested\");\n                }\n                \n                sourceBin.getWidgetCount().setCount(sourceBin.getWidgetCount().getCount() - widgets);\n                targetBin.getWidgetCount().setCount(targetBin.getWidgetCount().getCount() + widgets);\n                \n                return true;\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    targetBin.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    sourceBin.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    static class WidgetCount {\n        private int count;\n        \n        public WidgetCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n    }\n    \n    static class Bin {\n        private final String name;\n        private final WidgetCount widgetCount;\n        private final ReentrantLock lock;\n        \n        public Bin(String name, int initialCount) {\n            this.name = name;\n            this.widgetCount = new WidgetCount(initialCount);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public WidgetCount getWidgetCount() {\n            return widgetCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    static class NotEnoughWidgetsException extends Exception {\n        public NotEnoughWidgetsException(String message) {\n            super(message);\n        }\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class WidgetTransferSystem {\n    \n    private static final Random random = new Random();\n    \n    static class NotEnoughWidgetsException extends Exception {\n        public NotEnoughWidgetsException(String message) {\n            super(message);\n        }\n    }\n    \n    static class WidgetCount {\n        private int count;\n        \n        public WidgetCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void add(int amount) {\n            this.count += amount;\n        }\n        \n        public void subtract(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Bin {\n        private final String name;\n        private final WidgetCount widgetCount;\n        private final ReentrantLock lock;\n        \n        public Bin(String name, int initialCount) {\n            this.name = name;\n            this.widgetCount = new WidgetCount(initialCount);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public WidgetCount getWidgetCount() {\n            return widgetCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    public static boolean move(Bin sourceBin, Bin targetBin, int widgetsToMove, \n                               long timeout, TimeUnit timeUnit) throws NotEnoughWidgetsException {\n        long deadline = System.nanoTime() + timeUnit.toNanos(timeout);\n        \n        while (System.nanoTime() < deadline) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = deadline - System.nanoTime();\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = sourceBin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                \n                if (sourceLocked) {\n                    remainingTime = deadline - System.nanoTime();\n                    if (remainingTime <= 0) {\n                        return false;\n                    }\n                    \n                    targetLocked = targetBin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                    \n                    if (targetLocked) {\n                        if (sourceBin.getWidgetCount().getCount() >= widgetsToMove) {\n                            sourceBin.getWidgetCount().subtract(widgetsToMove);\n                            targetBin.getWidgetCount().add(widgetsToMove);\n                            return true;\n                        } else {\n                            throw new NotEnoughWidgetsException(\n                                \"Source bin \" + sourceBin.getName() + \" has only \" + \n                                sourceBin.getWidgetCount().getCount() + \" widgets, but \" + \n                                widgetsToMove + \" were requested\");\n                        }\n                    }\n                }\n                \n                if (!targetLocked && System.nanoTime() < deadline) {\n                    try {\n                        Thread.sleep(calculateFixedDelay() + calculateRandomDelay());\n                    } catch (InterruptedException e) {\n                        Thread.currentThread().interrupt();\n                        return false;\n                    }\n                }\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    targetBin.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    sourceBin.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long calculateFixedDelay() {\n        return 10;\n    }\n    \n    private static long calculateRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    public static void main(String[] args) {\n        Bin binA = new Bin(\"BinA\", 100);\n        Bin binB = new Bin(\"BinB\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(binA, binB, 10, 2, TimeUnit.SECONDS);\n                    if (success) {\n                        System.out.println(\"Thread 1: Moved 10 widgets from BinA to BinB\");\n                    } else {\n                        System.out.println(\"Thread 1: Failed to acquire locks in time\");\n                    }\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(binB, binA, 5, 2, TimeUnit.SECONDS);\n                    if (success) {\n                        System.out.println(\"Thread 2: Moved 5 widgets from BinB to BinA\");\n                    } else {\n                        System.out.println(\"Thread 2: Failed to acquire locks in time\");\n                    }\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"Final BinA count: \" + binA.getWidgetCount().getCount());\n        System.out.println(\"Final BinB count: \" + binB.getWidgetCount().getCount());\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class WidgetTransferSystem {\n    \n    private static final Random random = new Random();\n    \n    static class NotEnoughWidgetsException extends Exception {\n        public NotEnoughWidgetsException(String message) {\n            super(message);\n        }\n    }\n    \n    static class WidgetCount {\n        private int count;\n        \n        public WidgetCount(int count) {\n            this.count = count;\n        }\n        \n        public int getCount() {\n            return count;\n        }\n        \n        public void setCount(int count) {\n            this.count = count;\n        }\n        \n        public void add(int amount) {\n            this.count += amount;\n        }\n        \n        public void subtract(int amount) {\n            this.count -= amount;\n        }\n    }\n    \n    static class Bin {\n        private final String name;\n        private final WidgetCount widgetCount;\n        private final ReentrantLock lock;\n        \n        public Bin(String name, int initialCount) {\n            this.name = name;\n            this.widgetCount = new WidgetCount(initialCount);\n            this.lock = new ReentrantLock();\n        }\n        \n        public String getName() {\n            return name;\n        }\n        \n        public WidgetCount getWidgetCount() {\n            return widgetCount;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n    }\n    \n    public static boolean move(Bin sourceBin, Bin targetBin, int numberOfWidgets, \n                               long timeout, TimeUnit timeUnit) throws NotEnoughWidgetsException {\n        long startTime = System.nanoTime();\n        long timeoutNanos = timeUnit.toNanos(timeout);\n        \n        while (System.nanoTime() - startTime < timeoutNanos) {\n            boolean sourceLocked = false;\n            boolean targetLocked = false;\n            \n            try {\n                long remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                sourceLocked = sourceBin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!sourceLocked) {\n                    return false;\n                }\n                \n                remainingTime = timeoutNanos - (System.nanoTime() - startTime);\n                if (remainingTime <= 0) {\n                    return false;\n                }\n                \n                targetLocked = targetBin.getLock().tryLock(remainingTime, TimeUnit.NANOSECONDS);\n                if (!targetLocked) {\n                    Thread.sleep(getFixedDelay() + getRandomDelay());\n                    continue;\n                }\n                \n                if (sourceBin.getWidgetCount().getCount() < numberOfWidgets) {\n                    throw new NotEnoughWidgetsException(\"Source bin does not have enough widgets\");\n                }\n                \n                sourceBin.getWidgetCount().subtract(numberOfWidgets);\n                targetBin.getWidgetCount().add(numberOfWidgets);\n                \n                return true;\n                \n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            } finally {\n                if (targetLocked) {\n                    targetBin.getLock().unlock();\n                }\n                if (sourceLocked) {\n                    sourceBin.getLock().unlock();\n                }\n            }\n        }\n        \n        return false;\n    }\n    \n    private static long getFixedDelay() {\n        return 10;\n    }\n    \n    private static long getRandomDelay() {\n        return random.nextInt(50);\n    }\n    \n    public static void main(String[] args) {\n        Bin bin1 = new Bin(\"Bin1\", 100);\n        Bin bin2 = new Bin(\"Bin2\", 50);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(bin1, bin2, 10, 1, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 1 - Move \" + (i + 1) + \": \" + \n                        (success ? \"Success\" : \"Failed\") + \n                        \" | Bin1: \" + bin1.getWidgetCount().getCount() + \n                        \", Bin2: \" + bin2.getWidgetCount().getCount());\n                    Thread.sleep(100);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 1 - Move \" + (i + 1) + \": \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    boolean success = move(bin2, bin1, 5, 1, TimeUnit.SECONDS);\n                    System.out.println(\"Thread 2 - Move \" + (i + 1) + \": \" + \n                        (success ? \"Success\" : \"Failed\") + \n                        \" | Bin1: \" + bin1.getWidgetCount().getCount() + \n                        \", Bin2: \" + bin2.getWidgetCount().getCount());\n                    Thread.sleep(150);\n                } catch (NotEnoughWidgetsException e) {\n                    System.out.println(\"Thread 2 - Move \" + (i + 1) + \": \" + e.getMessage());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final state - Bin1: \" + bin1.getWidgetCount().getCount() + \n                          \", Bin2: \" + bin2.getWidgetCount().getCount());\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Candidate for lock splitting. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a class named ServerStatusBeforeSplit that maintains two sets of strings: one for devices and one for tasks. Both sets should be initialized in the constructor using HashSet<String>. All modification methods—such as inserting or deleting a device or task—should be synchronized on the instance (this) to ensure thread safety when multiple threads access the class concurrently. Provide four synchronized methods: addUser(String u), addQuery(String q), removeUser(String u), and removeQuery(String q)—each performing the corresponding operation on its respective set. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> devices;\n    private final Set<String> tasks;\n    \n    public ServerStatusBeforeSplit() {\n        this.devices = new HashSet<String>();\n        this.tasks = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        devices.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        tasks.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        devices.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        tasks.remove(q);\n    }\n    \n    public synchronized int getDeviceCount() {\n        return devices.size();\n    }\n    \n    public synchronized int getTaskCount() {\n        return tasks.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 2 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Devices: \" + server.getDeviceCount());\n        System.out.println(\"Tasks: \" + server.getTaskCount());\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> devices;\n    private final Set<String> tasks;\n    \n    public ServerStatusBeforeSplit() {\n        this.devices = new HashSet<String>();\n        this.tasks = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        devices.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        tasks.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        devices.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        tasks.remove(q);\n    }\n    \n    public synchronized int getDeviceCount() {\n        return devices.size();\n    }\n    \n    public synchronized int getTaskCount() {\n        return tasks.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 2 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Devices: \" + server.getDeviceCount());\n        System.out.println(\"Tasks: \" + server.getTaskCount());\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class ServerStatusBeforeSplit {\n    private final Set<String> devices;\n    private final Set<String> tasks;\n    \n    public ServerStatusBeforeSplit() {\n        this.devices = new HashSet<String>();\n        this.tasks = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        devices.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        tasks.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        devices.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        tasks.remove(q);\n    }\n    \n    public synchronized int getDeviceCount() {\n        return devices.size();\n    }\n    \n    public synchronized int getTaskCount() {\n        return tasks.size();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> future1 = executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        Future<?> future2 = executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        future1.get();\n        future2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Devices: \" + server.getDeviceCount());\n        System.out.println(\"Tasks: \" + server.getTaskCount());\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            true
        ],
        "ground_truth": "import java.util.HashSet;\nimport java.util.Set;\n\npublic class ServerStatusBeforeSplit {\npublic final Set<String> users;\npublic final Set<String> queries;\n\npublic ServerStatusBeforeSplit() {\nusers = new HashSet<>();\nqueries = new HashSet<>();\n}\n\npublic synchronized void addUser(String u) {\nusers.add(u);\n}\n\npublic synchronized void addQuery(String q) {\nqueries.add(q);\n}\n\npublic synchronized void removeUser(String u) {\nusers.remove(u);\n}\n\npublic synchronized void removeQuery(String q) {\nqueries.remove(q);\n}\n\npublic synchronized Set<String> getActiveUsers() {\nreturn new HashSet<>(users);\n}\n\npublic synchronized Set<String> getActiveQueries() {\nreturn new HashSet<>(queries);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nServerStatusBeforeSplit status = new ServerStatusBeforeSplit();\n\nThread t1 = new Thread(() -> {\nstatus.addUser(\"user1\");\nstatus.addQuery(\"query1\");\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user1\");\nstatus.removeQuery(\"query1\");\n});\n\nThread t2 = new Thread(() -> {\nstatus.addUser(\"user2\");\nstatus.addQuery(\"query2\");\ntry {\nThread.sleep(300);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user2\");\nstatus.removeQuery(\"query2\");\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final active users: \" + status.getActiveUsers());\nSystem.out.println(\"Final active queries: \" + status.getActiveQueries());\n}\n}",
        "max_depth": "89",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.66%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 50.96%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=149346,visited=81202,backtracked=229709,end=0\nsearch:             maxDepth=890,constraints=5266\nchoice generators:  thread=145363 (signal=0,lock=75367,sharedRef=51532,threadApi=2,reschedule=18461), data=0\nheap:               new=363308,released=212350,maxLive=1187,gcCycles=229603\ninstructions:       22619862\nmax memory:         1018MB\nloaded code:        classes=134,methods=2402\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/16/25 4:25 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/16/25 4:25 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "no errors detected"
        ],
        "codebleu_score": [
            58.74,
            58.74,
            59.48
        ],
        "llm_output": [
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> devices;\n    private final Set<String> tasks;\n    \n    public ServerStatusBeforeSplit() {\n        this.devices = new HashSet<String>();\n        this.tasks = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        devices.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        tasks.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        devices.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        tasks.remove(q);\n    }\n    \n    public synchronized int getDeviceCount() {\n        return devices.size();\n    }\n    \n    public synchronized int getTaskCount() {\n        return tasks.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 2 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Devices: \" + server.getDeviceCount());\n        System.out.println(\"Tasks: \" + server.getTaskCount());\n    }\n}\n```",
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> devices;\n    private final Set<String> tasks;\n    \n    public ServerStatusBeforeSplit() {\n        this.devices = new HashSet<String>();\n        this.tasks = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        devices.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        tasks.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        devices.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        tasks.remove(q);\n    }\n    \n    public synchronized int getDeviceCount() {\n        return devices.size();\n    }\n    \n    public synchronized int getTaskCount() {\n        return tasks.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 2 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Devices: \" + server.getDeviceCount());\n        System.out.println(\"Tasks: \" + server.getTaskCount());\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class ServerStatusBeforeSplit {\n    private final Set<String> devices;\n    private final Set<String> tasks;\n    \n    public ServerStatusBeforeSplit() {\n        this.devices = new HashSet<String>();\n        this.tasks = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        devices.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        tasks.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        devices.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        tasks.remove(q);\n    }\n    \n    public synchronized int getDeviceCount() {\n        return devices.size();\n    }\n    \n    public synchronized int getTaskCount() {\n        return tasks.size();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> future1 = executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        Future<?> future2 = executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        future1.get();\n        future2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Devices: \" + server.getDeviceCount());\n        System.out.println(\"Tasks: \" + server.getTaskCount());\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Candidate for lock splitting. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a class named ServerStatusBeforeSplit that maintains two sets of strings: one for notebooks and one for requests. Both sets should be initialized in the constructor using HashSet<String>. All modification methods—such as inserting or discarding a notebook or request—should be synchronized on the instance (this) to ensure thread safety when multiple threads access the class concurrently. Provide four synchronized methods: addUser(String u), addQuery(String q), removeUser(String u), and removeQuery(String q)—each performing the corresponding operation on its respective set. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> notebooks;\n    private final Set<String> requests;\n    \n    public ServerStatusBeforeSplit() {\n        this.notebooks = new HashSet<String>();\n        this.requests = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        notebooks.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        requests.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        notebooks.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        requests.remove(q);\n    }\n    \n    public synchronized int getNotebooksSize() {\n        return notebooks.size();\n    }\n    \n    public synchronized int getRequestsSize() {\n        return requests.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Notebooks: \" + server.getNotebooksSize());\n        System.out.println(\"Requests: \" + server.getRequestsSize());\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> notebooks;\n    private final Set<String> requests;\n    \n    public ServerStatusBeforeSplit() {\n        this.notebooks = new HashSet<String>();\n        this.requests = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        notebooks.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        requests.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        notebooks.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        requests.remove(q);\n    }\n    \n    public synchronized int getNotebooksSize() {\n        return notebooks.size();\n    }\n    \n    public synchronized int getRequestsSize() {\n        return requests.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"query\" + (i - 50));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Notebooks: \" + server.getNotebooksSize());\n        System.out.println(\"Requests: \" + server.getRequestsSize());\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ServerStatusBeforeSplit {\n    private final Set<String> notebooks;\n    private final Set<String> requests;\n    \n    public ServerStatusBeforeSplit() {\n        this.notebooks = new HashSet<String>();\n        this.requests = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        notebooks.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        requests.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        notebooks.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        requests.remove(q);\n    }\n    \n    public synchronized int getNotebooksSize() {\n        return notebooks.size();\n    }\n    \n    public synchronized int getRequestsSize() {\n        return requests.size();\n    }\n    \n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 10 == 0) {\n                    System.out.println(\"Thread 1: Added user\" + i + \" and query\" + i);\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 50; i < 150; i++) {\n                server.addUser(\"user\" + i);\n                server.removeQuery(\"query\" + (i - 50));\n                if (i % 10 == 0) {\n                    System.out.println(\"Thread 2: Added user\" + i + \" and removed query\" + (i - 50));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final notebooks size: \" + server.getNotebooksSize());\n        System.out.println(\"Final requests size: \" + server.getRequestsSize());\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.HashSet;\nimport java.util.Set;\n\npublic class ServerStatusBeforeSplit {\npublic final Set<String> users;\npublic final Set<String> queries;\n\npublic ServerStatusBeforeSplit() {\nusers = new HashSet<>();\nqueries = new HashSet<>();\n}\n\npublic synchronized void addUser(String u) {\nusers.add(u);\n}\n\npublic synchronized void addQuery(String q) {\nqueries.add(q);\n}\n\npublic synchronized void removeUser(String u) {\nusers.remove(u);\n}\n\npublic synchronized void removeQuery(String q) {\nqueries.remove(q);\n}\n\npublic synchronized Set<String> getActiveUsers() {\nreturn new HashSet<>(users);\n}\n\npublic synchronized Set<String> getActiveQueries() {\nreturn new HashSet<>(queries);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nServerStatusBeforeSplit status = new ServerStatusBeforeSplit();\n\nThread t1 = new Thread(() -> {\nstatus.addUser(\"user1\");\nstatus.addQuery(\"query1\");\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user1\");\nstatus.removeQuery(\"query1\");\n});\n\nThread t2 = new Thread(() -> {\nstatus.addUser(\"user2\");\nstatus.addQuery(\"query2\");\ntry {\nThread.sleep(300);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user2\");\nstatus.removeQuery(\"query2\");\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final active users: \" + status.getActiveUsers());\nSystem.out.println(\"Final active queries: \" + status.getActiveQueries());\n}\n}",
        "max_depth": "89",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/16/25 4:26 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/16/25 4:26 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nServerStatusBeforeSplit.main()\n====================================================== search started: 11/16/25 4:26 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            58.74,
            58.74,
            56.89
        ],
        "llm_output": [
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> notebooks;\n    private final Set<String> requests;\n    \n    public ServerStatusBeforeSplit() {\n        this.notebooks = new HashSet<String>();\n        this.requests = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        notebooks.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        requests.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        notebooks.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        requests.remove(q);\n    }\n    \n    public synchronized int getNotebooksSize() {\n        return notebooks.size();\n    }\n    \n    public synchronized int getRequestsSize() {\n        return requests.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Notebooks: \" + server.getNotebooksSize());\n        System.out.println(\"Requests: \" + server.getRequestsSize());\n    }\n}\n```",
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> notebooks;\n    private final Set<String> requests;\n    \n    public ServerStatusBeforeSplit() {\n        this.notebooks = new HashSet<String>();\n        this.requests = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        notebooks.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        requests.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        notebooks.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        requests.remove(q);\n    }\n    \n    public synchronized int getNotebooksSize() {\n        return notebooks.size();\n    }\n    \n    public synchronized int getRequestsSize() {\n        return requests.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"query\" + (i - 50));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Notebooks: \" + server.getNotebooksSize());\n        System.out.println(\"Requests: \" + server.getRequestsSize());\n    }\n}\n```",
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ServerStatusBeforeSplit {\n    private final Set<String> notebooks;\n    private final Set<String> requests;\n    \n    public ServerStatusBeforeSplit() {\n        this.notebooks = new HashSet<String>();\n        this.requests = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        notebooks.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        requests.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        notebooks.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        requests.remove(q);\n    }\n    \n    public synchronized int getNotebooksSize() {\n        return notebooks.size();\n    }\n    \n    public synchronized int getRequestsSize() {\n        return requests.size();\n    }\n    \n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 10 == 0) {\n                    System.out.println(\"Thread 1: Added user\" + i + \" and query\" + i);\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 50; i < 150; i++) {\n                server.addUser(\"user\" + i);\n                server.removeQuery(\"query\" + (i - 50));\n                if (i % 10 == 0) {\n                    System.out.println(\"Thread 2: Added user\" + i + \" and removed query\" + (i - 50));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final notebooks size: \" + server.getNotebooksSize());\n        System.out.println(\"Final requests size: \" + server.getRequestsSize());\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Candidate for lock splitting. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a class named ServerStatusBeforeSplit that maintains two sets of strings: one for vehicles and one for events. Both sets should be initialized in the constructor using HashSet<String>. All modification methods—such as registering or eliminating a vehicle or event—should be synchronized on the instance (this) to ensure thread safety when multiple threads access the class concurrently. Provide four synchronized methods: addUser(String u), addQuery(String q), removeUser(String u), and removeQuery(String q)—each performing the corresponding operation on its respective set. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> vehicles;\n    private final Set<String> events;\n    \n    public ServerStatusBeforeSplit() {\n        this.vehicles = new HashSet<String>();\n        this.events = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        vehicles.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        events.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        vehicles.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        events.remove(q);\n    }\n    \n    public synchronized int getVehicleCount() {\n        return vehicles.size();\n    }\n    \n    public synchronized int getEventCount() {\n        return events.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"vehicle_\" + i);\n                server.addQuery(\"event_\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"vehicle_\" + (i / 2));\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"vehicle_\" + i);\n                server.addQuery(\"event_\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"event_\" + (i / 3));\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Vehicles: \" + server.getVehicleCount());\n        System.out.println(\"Events: \" + server.getEventCount());\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> vehicles;\n    private final Set<String> events;\n    \n    public ServerStatusBeforeSplit() {\n        this.vehicles = new HashSet<String>();\n        this.events = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        vehicles.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        events.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        vehicles.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        events.remove(q);\n    }\n    \n    public synchronized int getVehicleCount() {\n        return vehicles.size();\n    }\n    \n    public synchronized int getEventCount() {\n        return events.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> task1 = executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"vehicle\" + i);\n                server.addQuery(\"event\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"vehicle\" + (i / 2));\n                }\n            }\n        });\n        \n        Future<?> task2 = executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"vehicle\" + i);\n                server.addQuery(\"event\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"event\" + (i / 3));\n                }\n            }\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Vehicles: \" + server.getVehicleCount());\n        System.out.println(\"Events: \" + server.getEventCount());\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class ServerStatusBeforeSplit {\n    private final Set<String> vehicles;\n    private final Set<String> events;\n    \n    public ServerStatusBeforeSplit() {\n        this.vehicles = new HashSet<String>();\n        this.events = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        vehicles.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        events.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        vehicles.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        events.remove(q);\n    }\n    \n    public synchronized int getVehicleCount() {\n        return vehicles.size();\n    }\n    \n    public synchronized int getEventCount() {\n        return events.size();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"vehicle\" + i);\n                server.addQuery(\"event\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"vehicle\" + (i - 1));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"vehicle\" + i);\n                server.addQuery(\"event\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"event\" + (i - 2));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Vehicles: \" + server.getVehicleCount());\n        System.out.println(\"Events: \" + server.getEventCount());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            false
        ],
        "ground_truth": "import java.util.HashSet;\nimport java.util.Set;\n\npublic class ServerStatusBeforeSplit {\npublic final Set<String> users;\npublic final Set<String> queries;\n\npublic ServerStatusBeforeSplit() {\nusers = new HashSet<>();\nqueries = new HashSet<>();\n}\n\npublic synchronized void addUser(String u) {\nusers.add(u);\n}\n\npublic synchronized void addQuery(String q) {\nqueries.add(q);\n}\n\npublic synchronized void removeUser(String u) {\nusers.remove(u);\n}\n\npublic synchronized void removeQuery(String q) {\nqueries.remove(q);\n}\n\npublic synchronized Set<String> getActiveUsers() {\nreturn new HashSet<>(users);\n}\n\npublic synchronized Set<String> getActiveQueries() {\nreturn new HashSet<>(queries);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nServerStatusBeforeSplit status = new ServerStatusBeforeSplit();\n\nThread t1 = new Thread(() -> {\nstatus.addUser(\"user1\");\nstatus.addQuery(\"query1\");\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user1\");\nstatus.removeQuery(\"query1\");\n});\n\nThread t2 = new Thread(() -> {\nstatus.addUser(\"user2\");\nstatus.addQuery(\"query2\");\ntry {\nThread.sleep(300);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user2\");\nstatus.removeQuery(\"query2\");\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final active users: \" + status.getActiveUsers());\nSystem.out.println(\"Final active queries: \" + status.getActiveQueries());\n}\n}",
        "max_depth": "89",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.75%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 50.86%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=146602,visited=79623,backtracked=225356,end=0\nsearch:             maxDepth=890,constraints=5392\nchoice generators:  thread=142511 (signal=0,lock=73832,sharedRef=51625,threadApi=2,reschedule=17051), data=0\nheap:               new=357019,released=211512,maxLive=1197,gcCycles=225091\ninstructions:       21350973\nmax memory:         1018MB\nloaded code:        classes=134,methods=2401\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.71%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 50.91%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=151782,visited=81447,backtracked=232343,end=0\nsearch:             maxDepth=890,constraints=6199\nchoice generators:  thread=147092 (signal=0,lock=76126,sharedRef=56697,threadApi=2,reschedule=14266), data=0\nheap:               new=368930,released=212445,maxLive=1154,gcCycles=230727\ninstructions:       20830658\nmax memory:         1018MB\nloaded code:        classes=135,methods=2403\n\n====================================================== search finished",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nServerStatusBeforeSplit.main()\n====================================================== search started: 11/16/25 4:27 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            59.94,
            61.79,
            54.63
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> vehicles;\n    private final Set<String> events;\n    \n    public ServerStatusBeforeSplit() {\n        this.vehicles = new HashSet<String>();\n        this.events = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        vehicles.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        events.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        vehicles.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        events.remove(q);\n    }\n    \n    public synchronized int getVehicleCount() {\n        return vehicles.size();\n    }\n    \n    public synchronized int getEventCount() {\n        return events.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"vehicle_\" + i);\n                server.addQuery(\"event_\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"vehicle_\" + (i / 2));\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"vehicle_\" + i);\n                server.addQuery(\"event_\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"event_\" + (i / 3));\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Vehicles: \" + server.getVehicleCount());\n        System.out.println(\"Events: \" + server.getEventCount());\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> vehicles;\n    private final Set<String> events;\n    \n    public ServerStatusBeforeSplit() {\n        this.vehicles = new HashSet<String>();\n        this.events = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        vehicles.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        events.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        vehicles.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        events.remove(q);\n    }\n    \n    public synchronized int getVehicleCount() {\n        return vehicles.size();\n    }\n    \n    public synchronized int getEventCount() {\n        return events.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> task1 = executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"vehicle\" + i);\n                server.addQuery(\"event\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"vehicle\" + (i / 2));\n                }\n            }\n        });\n        \n        Future<?> task2 = executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"vehicle\" + i);\n                server.addQuery(\"event\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"event\" + (i / 3));\n                }\n            }\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Vehicles: \" + server.getVehicleCount());\n        System.out.println(\"Events: \" + server.getEventCount());\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class ServerStatusBeforeSplit {\n    private final Set<String> vehicles;\n    private final Set<String> events;\n    \n    public ServerStatusBeforeSplit() {\n        this.vehicles = new HashSet<String>();\n        this.events = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        vehicles.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        events.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        vehicles.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        events.remove(q);\n    }\n    \n    public synchronized int getVehicleCount() {\n        return vehicles.size();\n    }\n    \n    public synchronized int getEventCount() {\n        return events.size();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"vehicle\" + i);\n                server.addQuery(\"event\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"vehicle\" + (i - 1));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"vehicle\" + i);\n                server.addQuery(\"event\" + i);\n                if (i % 5 == 0) {\n                    server.removeQuery(\"event\" + (i - 2));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Vehicles: \" + server.getVehicleCount());\n        System.out.println(\"Events: \" + server.getEventCount());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Using confinement to ensure thread safety. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a thread-safe Java class called PersonSet that uses synchronization to ensure safe concurrent access to a set of Person objects. The class should encapsulate a Set<Person> variable, initialized as a HashSet. It should provide two synchronized methods: one to insert a Person object into the set, and another to verify if the set contains a specific Person object. Additionally, define the Person interface as a nested type within the class. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using `java`. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    private final Set<Person> personSet = new HashSet<>();\n    \n    public synchronized boolean insert(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> insertTask = executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                final int id = i;\n                Person person = new PersonImpl(\"Person\" + id, 20 + id);\n                personSet.insert(person);\n                System.out.println(\"Inserted: \" + person.getName());\n            }\n            return null;\n        });\n        \n        Future<Void> checkTask = executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 10; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean exists = personSet.contains(person);\n                System.out.println(\"Contains Person\" + i + \": \" + exists);\n            }\n            return null;\n        });\n        \n        insertTask.get();\n        checkTask.get();\n        \n        executor.shutdown();\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized boolean insert(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> insertTask = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.insert(person);\n                System.out.println(\"Inserted: \" + person.getName());\n            }\n            return null;\n        });\n        \n        Future<Void> checkTask = executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 7; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean exists = personSet.contains(person);\n                System.out.println(\"Contains Person\" + i + \": \" + exists);\n            }\n            return null;\n        });\n        \n        insertTask.get();\n        checkTask.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized boolean insert(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean inserted = personSet.insert(person);\n                System.out.println(\"Thread 1: Inserted \" + person.getName() + \" - \" + inserted);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 3; i < 8; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean inserted = personSet.insert(person);\n                System.out.println(\"Thread 2: Inserted \" + person.getName() + \" - \" + inserted);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        for (int i = 0; i < 10; i++) {\n            PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n            boolean exists = personSet.contains(person);\n            System.out.println(\"Main thread: Person\" + i + \" exists - \" + exists);\n        }\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\n/**\n* PersonSet\n*\n* A thread-safe set using synchronized methods,\n* adapted to be compatible with Java Pathfinder (JPF).\n*/\npublic class PersonSet {\nprivate final Set<Person> mySet = new HashSet<>();\n\npublic synchronized void addPerson(Person p) {\nmySet.add(p);\n}\n\npublic synchronized boolean containsPerson(Person p) {\nreturn mySet.contains(p);\n}\n\npublic interface Person {\nString getName();\n}\n\npublic static class SimplePerson implements Person {\nprivate final String name;\n\npublic SimplePerson(String name) {\nthis.name = name;\n}\n\n@Override\npublic String getName() {\nreturn name;\n}\n\n@Override\npublic boolean equals(Object o) {\nif (this == o) return true;\nif (!(o instanceof SimplePerson)) return false;\nSimplePerson that = (SimplePerson) o;\nreturn Objects.equals(name, that.name);\n}\n\n@Override\npublic int hashCode() {\nreturn Objects.hash(name);\n}\n\n@Override\npublic String toString() {\nreturn \"Person{name='\" + name + \"'}\";\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nPersonSet personSet = new PersonSet();\n\nThread t1 = new Thread(() -> {\nPerson p = new SimplePerson(\"Alice\");\npersonSet.addPerson(p);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + p);\n});\n\nThread t2 = new Thread(() -> {\nPerson p = new SimplePerson(\"Bob\");\npersonSet.addPerson(p);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + p);\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nList<String> checkNames = Arrays.asList(\"Alice\", \"Frank\");\nfor (String name : checkNames) {\nPerson p = new SimplePerson(name);\nSystem.out.println(p.getName() + \" is in set? \" + personSet.containsPerson(p));\n}\n\nSystem.out.println(\"Program completed.\");\n}\n}",
        "max_depth": "31",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 56.02%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 59.02%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.67%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=94036,visited=152246,backtracked=246014,end=73\nsearch:             maxDepth=310,constraints=95\nchoice generators:  thread=94004 (signal=0,lock=17264,sharedRef=60621,threadApi=674,reschedule=10238), data=0\nheap:               new=517622,released=402825,maxLive=1046,gcCycles=241858\ninstructions:       13268668\nmax memory:         1019MB\nloaded code:        classes=143,methods=2630\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 39.15%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 19.75%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 30.05%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=114126,visited=68831,backtracked=182710,end=42772\nsearch:             maxDepth=310,constraints=7959\nchoice generators:  thread=108938 (signal=0,lock=18,sharedRef=47862,threadApi=3,reschedule=52820), data=0\nheap:               new=337546,released=3113558,maxLive=1037,gcCycles=182956\ninstructions:       70519321\nmax memory:         1016MB\nloaded code:        classes=143,methods=2630\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.12%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.04%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=153603,visited=115146,backtracked=268482,end=0\nsearch:             maxDepth=310,constraints=70735\nchoice generators:  thread=93179 (signal=0,lock=13334,sharedRef=55179,threadApi=9935,reschedule=2634), data=0\nheap:               new=620290,released=317202,maxLive=774,gcCycles=266140\ninstructions:       29839970\nmax memory:         1019MB\nloaded code:        classes=138,methods=2418\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            55.07,
            55.03,
            54.48
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    private final Set<Person> personSet = new HashSet<>();\n    \n    public synchronized boolean insert(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> insertTask = executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                final int id = i;\n                Person person = new PersonImpl(\"Person\" + id, 20 + id);\n                personSet.insert(person);\n                System.out.println(\"Inserted: \" + person.getName());\n            }\n            return null;\n        });\n        \n        Future<Void> checkTask = executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 10; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean exists = personSet.contains(person);\n                System.out.println(\"Contains Person\" + i + \": \" + exists);\n            }\n            return null;\n        });\n        \n        insertTask.get();\n        checkTask.get();\n        \n        executor.shutdown();\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized boolean insert(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> insertTask = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.insert(person);\n                System.out.println(\"Inserted: \" + person.getName());\n            }\n            return null;\n        });\n        \n        Future<Void> checkTask = executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 7; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean exists = personSet.contains(person);\n                System.out.println(\"Contains Person\" + i + \": \" + exists);\n            }\n            return null;\n        });\n        \n        insertTask.get();\n        checkTask.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}\n```",
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized boolean insert(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean inserted = personSet.insert(person);\n                System.out.println(\"Thread 1: Inserted \" + person.getName() + \" - \" + inserted);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 3; i < 8; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean inserted = personSet.insert(person);\n                System.out.println(\"Thread 2: Inserted \" + person.getName() + \" - \" + inserted);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        for (int i = 0; i < 10; i++) {\n            PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n            boolean exists = personSet.contains(person);\n            System.out.println(\"Main thread: Person\" + i + \" exists - \" + exists);\n        }\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using confinement to ensure thread safety. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a thread-safe Java class called PersonSet that uses synchronization to ensure safe concurrent access to a set of Person objects. The class should encapsulate a Set<Person> variable, initialized as a HashSet. It should provide two synchronized methods: one to register a Person object into the set, and another to determine if the set contains a specific Person object. Additionally, define the Person interface as a nested type within the class. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized void register(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Person person1 = new PersonImpl(\"Alice\", 25);\n        Person person2 = new PersonImpl(\"Bob\", 30);\n        Person person3 = new PersonImpl(\"Charlie\", 35);\n        \n        Future<?> future1 = executor.submit(() -> {\n            personSet.register(person1);\n            personSet.register(person2);\n            System.out.println(\"Thread 1: Registered Alice and Bob\");\n            System.out.println(\"Thread 1: Contains Alice? \" + personSet.contains(person1));\n        });\n        \n        Future<?> future2 = executor.submit(() -> {\n            personSet.register(person3);\n            System.out.println(\"Thread 2: Registered Charlie\");\n            System.out.println(\"Thread 2: Contains Bob? \" + personSet.contains(person2));\n            System.out.println(\"Thread 2: Contains Charlie? \" + personSet.contains(person3));\n        });\n        \n        future1.get();\n        future2.get();\n        \n        System.out.println(\"Main thread: Contains Alice? \" + personSet.contains(person1));\n        System.out.println(\"Main thread: Contains Bob? \" + personSet.contains(person2));\n        System.out.println(\"Main thread: Contains Charlie? \" + personSet.contains(person3));\n        \n        executor.shutdown();\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        PersonImpl person = (PersonImpl) o;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized void register(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.register(person);\n                System.out.println(\"Thread 1 registered: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 5; i < 10; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.register(person);\n                System.out.println(\"Thread 2 registered: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        Person checkPerson = new PersonImpl(\"Person3\", 23);\n        System.out.println(\"Contains Person3: \" + personSet.contains(checkPerson));\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    private final Set<Person> personSet = new HashSet<>();\n    \n    public synchronized void register(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.register(person);\n                System.out.println(\"Registered: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                boolean exists = personSet.contains(person);\n                System.out.println(\"Contains \" + person.getName() + \": \" + exists);\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\n/**\n* PersonSet\n*\n* A thread-safe set using synchronized methods,\n* adapted to be compatible with Java Pathfinder (JPF).\n*/\npublic class PersonSet {\nprivate final Set<Person> mySet = new HashSet<>();\n\npublic synchronized void addPerson(Person p) {\nmySet.add(p);\n}\n\npublic synchronized boolean containsPerson(Person p) {\nreturn mySet.contains(p);\n}\n\npublic interface Person {\nString getName();\n}\n\npublic static class SimplePerson implements Person {\nprivate final String name;\n\npublic SimplePerson(String name) {\nthis.name = name;\n}\n\n@Override\npublic String getName() {\nreturn name;\n}\n\n@Override\npublic boolean equals(Object o) {\nif (this == o) return true;\nif (!(o instanceof SimplePerson)) return false;\nSimplePerson that = (SimplePerson) o;\nreturn Objects.equals(name, that.name);\n}\n\n@Override\npublic int hashCode() {\nreturn Objects.hash(name);\n}\n\n@Override\npublic String toString() {\nreturn \"Person{name='\" + name + \"'}\";\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nPersonSet personSet = new PersonSet();\n\nThread t1 = new Thread(() -> {\nPerson p = new SimplePerson(\"Alice\");\npersonSet.addPerson(p);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + p);\n});\n\nThread t2 = new Thread(() -> {\nPerson p = new SimplePerson(\"Bob\");\npersonSet.addPerson(p);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + p);\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nList<String> checkNames = Arrays.asList(\"Alice\", \"Frank\");\nfor (String name : checkNames) {\nPerson p = new SimplePerson(name);\nSystem.out.println(p.getName() + \" is in set? \" + personSet.containsPerson(p));\n}\n\nSystem.out.println(\"Program completed.\");\n}\n}",
        "max_depth": "31",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 62.05%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 61.94%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 62.44%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=95059,visited=168919,backtracked=263921,end=266\nsearch:             maxDepth=142,constraints=0\nchoice generators:  thread=95056 (signal=0,lock=14442,sharedRef=62946,threadApi=586,reschedule=7596), data=0\nheap:               new=365121,released=234009,maxLive=1030,gcCycles=256616\ninstructions:       15037055\nmax memory:         1019MB\nloaded code:        classes=144,methods=2632\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.03%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.40%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.96%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=150125,visited=113784,backtracked=263608,end=0\nsearch:             maxDepth=310,constraints=68531\nchoice generators:  thread=91573 (signal=0,lock=13198,sharedRef=54197,threadApi=9876,reschedule=2609), data=0\nheap:               new=789940,released=251458,maxLive=776,gcCycles=261291\ninstructions:       28627860\nmax memory:         1019MB\nloaded code:        classes=138,methods=2418\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.49%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.74%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=156700,visited=133099,backtracked=289498,end=0\nsearch:             maxDepth=310,constraints=66682\nchoice generators:  thread=99932 (signal=0,lock=14657,sharedRef=57967,threadApi=11805,reschedule=3313), data=0\nheap:               new=329997,released=596286,maxLive=759,gcCycles=277616\ninstructions:       30464586\nmax memory:         1019MB\nloaded code:        classes=138,methods=2418\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            56.9,
            56.8,
            53.68
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized void register(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Person person1 = new PersonImpl(\"Alice\", 25);\n        Person person2 = new PersonImpl(\"Bob\", 30);\n        Person person3 = new PersonImpl(\"Charlie\", 35);\n        \n        Future<?> future1 = executor.submit(() -> {\n            personSet.register(person1);\n            personSet.register(person2);\n            System.out.println(\"Thread 1: Registered Alice and Bob\");\n            System.out.println(\"Thread 1: Contains Alice? \" + personSet.contains(person1));\n        });\n        \n        Future<?> future2 = executor.submit(() -> {\n            personSet.register(person3);\n            System.out.println(\"Thread 2: Registered Charlie\");\n            System.out.println(\"Thread 2: Contains Bob? \" + personSet.contains(person2));\n            System.out.println(\"Thread 2: Contains Charlie? \" + personSet.contains(person3));\n        });\n        \n        future1.get();\n        future2.get();\n        \n        System.out.println(\"Main thread: Contains Alice? \" + personSet.contains(person1));\n        System.out.println(\"Main thread: Contains Bob? \" + personSet.contains(person2));\n        System.out.println(\"Main thread: Contains Charlie? \" + personSet.contains(person3));\n        \n        executor.shutdown();\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        PersonImpl person = (PersonImpl) o;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}\n```",
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized void register(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.register(person);\n                System.out.println(\"Thread 1 registered: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 5; i < 10; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.register(person);\n                System.out.println(\"Thread 2 registered: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        Person checkPerson = new PersonImpl(\"Person3\", 23);\n        System.out.println(\"Contains Person3: \" + personSet.contains(checkPerson));\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}\n```",
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    private final Set<Person> personSet = new HashSet<>();\n    \n    public synchronized void register(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean contains(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.register(person);\n                System.out.println(\"Registered: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                boolean exists = personSet.contains(person);\n                System.out.println(\"Contains \" + person.getName() + \": \" + exists);\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using confinement to ensure thread safety. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a thread-safe Java class called PersonSet that uses synchronization to ensure safe concurrent access to a set of Person objects. The class should encapsulate a Set<Person> variable, initialized as a HashSet. It should provide two synchronized methods: one to place a Person object into the set, and another to ascertain whether the set contains a specific Person object. Additionally, define the Person interface as a nested type within the class. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using java. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet = new HashSet<>();\n    \n    public synchronized void addPerson(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Added: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 7; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean contains = personSet.containsPerson(person);\n                System.out.println(\"Contains Person\" + i + \": \" + contains);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}",
            "import java.util.Set;\nimport java.util.HashSet;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized void addPerson(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Thread 1 added: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 3; i < 8; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                if (personSet.containsPerson(person)) {\n                    System.out.println(\"Thread 2 found: \" + person.getName());\n                } else {\n                    personSet.addPerson(person);\n                    System.out.println(\"Thread 2 added: \" + person.getName());\n                }\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized void addPerson(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Added: \" + person.getName());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 10; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean contains = personSet.containsPerson(person);\n                System.out.println(\"Contains \" + person.getName() + \": \" + contains);\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        PersonImpl person = (PersonImpl) o;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\n/**\n* PersonSet\n*\n* A thread-safe set using synchronized methods,\n* adapted to be compatible with Java Pathfinder (JPF).\n*/\npublic class PersonSet {\nprivate final Set<Person> mySet = new HashSet<>();\n\npublic synchronized void addPerson(Person p) {\nmySet.add(p);\n}\n\npublic synchronized boolean containsPerson(Person p) {\nreturn mySet.contains(p);\n}\n\npublic interface Person {\nString getName();\n}\n\npublic static class SimplePerson implements Person {\nprivate final String name;\n\npublic SimplePerson(String name) {\nthis.name = name;\n}\n\n@Override\npublic String getName() {\nreturn name;\n}\n\n@Override\npublic boolean equals(Object o) {\nif (this == o) return true;\nif (!(o instanceof SimplePerson)) return false;\nSimplePerson that = (SimplePerson) o;\nreturn Objects.equals(name, that.name);\n}\n\n@Override\npublic int hashCode() {\nreturn Objects.hash(name);\n}\n\n@Override\npublic String toString() {\nreturn \"Person{name='\" + name + \"'}\";\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nPersonSet personSet = new PersonSet();\n\nThread t1 = new Thread(() -> {\nPerson p = new SimplePerson(\"Alice\");\npersonSet.addPerson(p);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + p);\n});\n\nThread t2 = new Thread(() -> {\nPerson p = new SimplePerson(\"Bob\");\npersonSet.addPerson(p);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + p);\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nList<String> checkNames = Arrays.asList(\"Alice\", \"Frank\");\nfor (String name : checkNames) {\nPerson p = new SimplePerson(name);\nSystem.out.println(p.getName() + \" is in set? \" + personSet.containsPerson(p));\n}\n\nSystem.out.println(\"Program completed.\");\n}\n}",
        "max_depth": "31",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.45%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.70%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=158238,visited=132492,backtracked=290422,end=0\nsearch:             maxDepth=310,constraints=68059\nchoice generators:  thread=100394 (signal=0,lock=16142,sharedRef=54896,threadApi=13961,reschedule=3089), data=0\nheap:               new=312445,released=582073,maxLive=759,gcCycles=289325\ninstructions:       30088468\nmax memory:         1020MB\nloaded code:        classes=138,methods=2418\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.27%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.14%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=163826,visited=127342,backtracked=290864,end=0\nsearch:             maxDepth=310,constraints=72014\nchoice generators:  thread=102138 (signal=0,lock=20383,sharedRef=57067,threadApi=8668,reschedule=3896), data=0\nheap:               new=279758,released=532594,maxLive=765,gcCycles=288494\ninstructions:       30505505\nmax memory:         1019MB\nloaded code:        classes=138,methods=2418\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.04%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.03%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=137395,visited=99774,backtracked=236889,end=0\nsearch:             maxDepth=310,constraints=63722\nchoice generators:  thread=82767 (signal=0,lock=17079,sharedRef=49505,threadApi=1862,reschedule=2570), data=0\nheap:               new=581510,released=497828,maxLive=1029,gcCycles=236009\ninstructions:       25045029\nmax memory:         1019MB\nloaded code:        classes=139,methods=2598\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            54.82,
            54.76,
            58.67
        ],
        "llm_output": [
            "```java\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet = new HashSet<>();\n    \n    public synchronized void addPerson(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Added: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 7; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean contains = personSet.containsPerson(person);\n                System.out.println(\"Contains Person\" + i + \": \" + contains);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}\n```",
            "```java\nimport java.util.Set;\nimport java.util.HashSet;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized void addPerson(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Thread 1 added: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 3; i < 8; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                if (personSet.containsPerson(person)) {\n                    System.out.println(\"Thread 2 found: \" + person.getName());\n                } else {\n                    personSet.addPerson(person);\n                    System.out.println(\"Thread 2 added: \" + person.getName());\n                }\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized void addPerson(Person person) {\n        personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Added: \" + person.getName());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 10; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean contains = personSet.containsPerson(person);\n                System.out.println(\"Contains \" + person.getName() + \": \" + contains);\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        PersonImpl person = (PersonImpl) o;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Vehicle tracker that safely publishes underlying state. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called PublishingVehicleTracker that supervises the coordinates of vehicles in a thread-safe manner. The class should allow safe publication of its internal state to prevent unintended alterations from external code. Use a thread-safe map implementation to store vehicle coordinates, where each entry maps a vehicle ID (String) to a SafePoint object that represents its current positions. Provide an unmodifiable view of the full coordinate map for external access. Include methods to retrieve the full map of vehicle coordinates, get the coordinates of a specific vehicle by ID, and update the coordinates of a vehicle by setting its x and y values. Ensure that attempting to refresh a non-existent vehicle triggers an appropriate exception. The design should follow best practices for encapsulation and thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to conduct tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using `java`. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> locations) {\n        this.locations = new ConcurrentHashMap<>(locations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"Vehicle not found: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> locations = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : locations.entrySet()) {\n            SafePoint point = entry.getValue();\n            System.out.println(entry.getKey() + \": [\" + point.get()[0] + \", \" + point.get()[1] + \"]\");\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}",
            "import java.util.Collections;\nimport java.util.Map;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass SafePoint {\n    private int x;\n    private int y;\n\n    public SafePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.x, p.y);\n    }\n\n    public synchronized int getX() {\n        return x;\n    }\n\n    public synchronized int getY() {\n        return y;\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public synchronized SafePoint get() {\n        return new SafePoint(this);\n    }\n}\n\nclass PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        locations = new ConcurrentHashMap<>(points);\n        unmodifiableMap = Collections.unmodifiableMap(locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        }\n        loc.set(x, y);\n    }\n}\n\npublic class VehicleTrackerDemo {\n    public static void main(String[] args) {\n        Map<String, SafePoint> initialLocations = new ConcurrentHashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle2\", new SafePoint(30, 40));\n        initialLocations.put(\"vehicle3\", new SafePoint(50, 60));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                SafePoint loc = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"Thread1 updated vehicle1: (\" + loc.getX() + \", \" + loc.getY() + \")\");\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 15, i * 25);\n                SafePoint loc = tracker.getLocation(\"vehicle2\");\n                System.out.println(\"Thread2 updated vehicle2: (\" + loc.getX() + \", \" + loc.getY() + \")\");\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        try {\n            Thread.sleep(200);\n            Map<String, SafePoint> allLocations = tracker.getLocations();\n            System.out.println(\"Main thread reading all locations:\");\n            for (Map.Entry<String, SafePoint> entry : allLocations.entrySet()) {\n                SafePoint point = entry.getValue();\n                System.out.println(entry.getKey() + \": (\" + point.getX() + \", \" + point.getY() + \")\");\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(2, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"Vehicle not found: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> locations = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : locations.entrySet()) {\n            SafePoint point = entry.getValue();\n            System.out.println(entry.getKey() + \": [\" + point.get()[0] + \", \" + point.get()[1] + \"]\");\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\nprivate final Map<String, SafePoint> locations;\nprivate final Map<String, SafePoint> unmodifiableMap;\n\npublic PublishingVehicleTracker(Map<String, SafePoint> locations) {\nthis.locations = new ConcurrentHashMap<>(locations);\nthis.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n}\n\npublic Map<String, SafePoint> getLocations() {\nreturn unmodifiableMap;\n}\n\npublic SafePoint getLocation(String id) {\nreturn locations.get(id);\n}\n\npublic void setLocation(String id, int x, int y) {\nif (!locations.containsKey(id))\nthrow new IllegalArgumentException(\"invalid vehicle name: \" + id);\nlocations.get(id).set(x, y);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, SafePoint> initialPoints = new HashMap<>();\ninitialPoints.put(\"V1\", new SafePoint(0, 0));\ninitialPoints.put(\"V2\", new SafePoint(10, 10));\ninitialPoints.put(\"V3\", new SafePoint(20, 20));\n\nPublishingVehicleTracker tracker = new PublishingVehicleTracker(initialPoints);\n\nThread[] threads = new Thread[2]; // fewer threads for faster JPF testing\n\nfor (int i = 0; i < 2; i++) {\nfinal int taskId = i;\nthreads[i] = new Thread(() -> {\nRandom rand = new Random();\nfor (int j = 0; j < 3; j++) { // fewer iterations\nString vehicleId = \"V\" + ((taskId % 3) + 1);\nint newX = rand.nextInt(6); // 0 to 5\nint newY = rand.nextInt(6); // 0 to 5\ntracker.setLocation(vehicleId, newX, newY);\nSystem.out.println(Thread.currentThread().getName() +\n\" updated \" + vehicleId + \" to (\" + newX + \", \" + newY + \")\");\ntry {\nThread.sleep(20); // shorter sleep\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\ntracker.getLocations().forEach((id, point) ->\nSystem.out.println(id + \": (\" + point.getX() + \", \" + point.getY() + \")\"));\n}\n}\n\nclass SafePoint {\nprivate int x, y;\n\npublic SafePoint(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\npublic SafePoint(SafePoint point) {\nthis(point.getX(), point.getY());\n}\n\npublic synchronized int getX() {\nreturn x;\n}\n\npublic synchronized int getY() {\nreturn y;\n}\n\npublic synchronized void set(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n}",
        "max_depth": "93",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.23%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.29%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=108472,visited=177444,backtracked=285038,end=10\nsearch:             maxDepth=930,constraints=16252\nchoice generators:  thread=96105 (signal=0,lock=7531,sharedRef=78917,threadApi=6761,reschedule=464), data=0\nheap:               new=92535,released=1463313,maxLive=851,gcCycles=255662\ninstructions:       33156454\nmax memory:         1019MB\nloaded code:        classes=157,methods=2690\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.45%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=119548,visited=168859,backtracked=287481,end=0\nsearch:             maxDepth=930,constraints=28347\nchoice generators:  thread=96739 (signal=0,lock=10154,sharedRef=79205,threadApi=2560,reschedule=25), data=0\nheap:               new=128231,released=1401772,maxLive=858,gcCycles=252987\ninstructions:       31551217\nmax memory:         1019MB\nloaded code:        classes=154,methods=2663\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.23%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.29%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=108896,visited=178451,backtracked=286433,end=10\nsearch:             maxDepth=930,constraints=16167\nchoice generators:  thread=96575 (signal=0,lock=7566,sharedRef=79326,threadApi=6796,reschedule=471), data=0\nheap:               new=93071,released=1471841,maxLive=851,gcCycles=256885\ninstructions:       33342117\nmax memory:         1019MB\nloaded code:        classes=157,methods=2690\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            60.35,
            58.39,
            57.19
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> locations) {\n        this.locations = new ConcurrentHashMap<>(locations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"Vehicle not found: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> locations = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : locations.entrySet()) {\n            SafePoint point = entry.getValue();\n            System.out.println(entry.getKey() + \": [\" + point.get()[0] + \", \" + point.get()[1] + \"]\");\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}\n```",
            "```java\nimport java.util.Collections;\nimport java.util.Map;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass SafePoint {\n    private int x;\n    private int y;\n\n    public SafePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.x, p.y);\n    }\n\n    public synchronized int getX() {\n        return x;\n    }\n\n    public synchronized int getY() {\n        return y;\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public synchronized SafePoint get() {\n        return new SafePoint(this);\n    }\n}\n\nclass PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        locations = new ConcurrentHashMap<>(points);\n        unmodifiableMap = Collections.unmodifiableMap(locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        }\n        loc.set(x, y);\n    }\n}\n\npublic class VehicleTrackerDemo {\n    public static void main(String[] args) {\n        Map<String, SafePoint> initialLocations = new ConcurrentHashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle2\", new SafePoint(30, 40));\n        initialLocations.put(\"vehicle3\", new SafePoint(50, 60));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                SafePoint loc = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"Thread1 updated vehicle1: (\" + loc.getX() + \", \" + loc.getY() + \")\");\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 15, i * 25);\n                SafePoint loc = tracker.getLocation(\"vehicle2\");\n                System.out.println(\"Thread2 updated vehicle2: (\" + loc.getX() + \", \" + loc.getY() + \")\");\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        try {\n            Thread.sleep(200);\n            Map<String, SafePoint> allLocations = tracker.getLocations();\n            System.out.println(\"Main thread reading all locations:\");\n            for (Map.Entry<String, SafePoint> entry : allLocations.entrySet()) {\n                SafePoint point = entry.getValue();\n                System.out.println(entry.getKey() + \": (\" + point.getX() + \", \" + point.getY() + \")\");\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(2, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"Vehicle not found: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> locations = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : locations.entrySet()) {\n            SafePoint point = entry.getValue();\n            System.out.println(entry.getKey() + \": [\" + point.get()[0] + \", \" + point.get()[1] + \"]\");\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Vehicle tracker that safely publishes underlying state. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called PublishingVehicleTracker that orchestrates the positions of vehicles in a thread-safe manner. The class should allow safe publication of its internal state to prevent unintended distortions from external code. Use a thread-safe map implementation to store vehicle positions, where each entry maps a vehicle ID (String) to a SafePoint object that represents its current coordinates. Provide an unmodifiable view of the full position map for external access. Include methods to retrieve the full map of vehicle positions, get the position of a specific vehicle by ID, and update the position of a vehicle by setting its x and y coordinates. Ensure that attempting to modify a non-existent vehicle produces an appropriate exception. The design should follow best practices for encapsulation and thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to execute tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using `java`. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> locations) {\n        this.locations = new ConcurrentHashMap<>(locations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such vehicle: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n        \n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                SafePoint point = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"Thread 1 - Vehicle1 position: \" + point.get()[0] + \", \" + point.get()[1]);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                SafePoint point = tracker.getLocation(\"vehicle2\");\n                System.out.println(\"Thread 2 - Vehicle2 position: \" + point.get()[0] + \", \" + point.get()[1]);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        Thread.sleep(200);\n        \n        Map<String, SafePoint> allLocations = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : allLocations.entrySet()) {\n            int[] coords = entry.getValue().get();\n            System.out.println(\"Main thread - \" + entry.getKey() + \": \" + coords[0] + \", \" + coords[1]);\n        }\n        \n        try {\n            tracker.setLocation(\"nonexistent\", 0, 0);\n        } catch (IllegalArgumentException e) {\n            System.out.println(\"Exception caught: \" + e.getMessage());\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"Vehicle not found: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> snapshot = tracker.getLocations();\n        snapshot.forEach((id, point) -> {\n            int[] coords = point.get();\n            System.out.println(id + \": [\" + coords[0] + \", \" + coords[1] + \"]\");\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(2, TimeUnit.SECONDS);\n\n        System.out.println(\"\\nFinal positions:\");\n        tracker.getLocations().forEach((id, point) -> {\n            int[] coords = point.get();\n            System.out.println(id + \": [\" + coords[0] + \", \" + coords[1] + \"]\");\n        });\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such vehicle: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> snapshot = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : snapshot.entrySet()) {\n            SafePoint point = entry.getValue();\n            System.out.println(entry.getKey() + \": [\" + point.get()[0] + \", \" + point.get()[1] + \"]\");\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\nprivate final Map<String, SafePoint> locations;\nprivate final Map<String, SafePoint> unmodifiableMap;\n\npublic PublishingVehicleTracker(Map<String, SafePoint> locations) {\nthis.locations = new ConcurrentHashMap<>(locations);\nthis.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n}\n\npublic Map<String, SafePoint> getLocations() {\nreturn unmodifiableMap;\n}\n\npublic SafePoint getLocation(String id) {\nreturn locations.get(id);\n}\n\npublic void setLocation(String id, int x, int y) {\nif (!locations.containsKey(id))\nthrow new IllegalArgumentException(\"invalid vehicle name: \" + id);\nlocations.get(id).set(x, y);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, SafePoint> initialPoints = new HashMap<>();\ninitialPoints.put(\"V1\", new SafePoint(0, 0));\ninitialPoints.put(\"V2\", new SafePoint(10, 10));\ninitialPoints.put(\"V3\", new SafePoint(20, 20));\n\nPublishingVehicleTracker tracker = new PublishingVehicleTracker(initialPoints);\n\nThread[] threads = new Thread[2]; // fewer threads for faster JPF testing\n\nfor (int i = 0; i < 2; i++) {\nfinal int taskId = i;\nthreads[i] = new Thread(() -> {\nRandom rand = new Random();\nfor (int j = 0; j < 3; j++) { // fewer iterations\nString vehicleId = \"V\" + ((taskId % 3) + 1);\nint newX = rand.nextInt(6); // 0 to 5\nint newY = rand.nextInt(6); // 0 to 5\ntracker.setLocation(vehicleId, newX, newY);\nSystem.out.println(Thread.currentThread().getName() +\n\" updated \" + vehicleId + \" to (\" + newX + \", \" + newY + \")\");\ntry {\nThread.sleep(20); // shorter sleep\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\ntracker.getLocations().forEach((id, point) ->\nSystem.out.println(id + \": (\" + point.getX() + \", \" + point.getY() + \")\"));\n}\n}\n\nclass SafePoint {\nprivate int x, y;\n\npublic SafePoint(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\npublic SafePoint(SafePoint point) {\nthis(point.getX(), point.getY());\n}\n\npublic synchronized int getX() {\nreturn x;\n}\n\npublic synchronized int getY() {\nreturn y;\n}\n\npublic synchronized void set(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n}",
        "max_depth": "93",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.42%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.43%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=103846,visited=168414,backtracked=271360,end=0\nsearch:             maxDepth=930,constraints=16559\nchoice generators:  thread=91355 (signal=0,lock=9516,sharedRef=77238,threadApi=2227,reschedule=20), data=0\nheap:               new=137038,released=1683515,maxLive=887,gcCycles=249413\ninstructions:       31089569\nmax memory:         1019MB\nloaded code:        classes=162,methods=2730\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.08%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.27%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.32%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=112474,visited=157692,backtracked=269281,end=6\nsearch:             maxDepth=930,constraints=26766\nchoice generators:  thread=90780 (signal=0,lock=6554,sharedRef=73405,threadApi=5818,reschedule=306), data=0\nheap:               new=563713,released=84618,maxLive=826,gcCycles=243759\ninstructions:       33228486\nmax memory:         1019MB\nloaded code:        classes=148,methods=2610\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.23%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.29%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=109166,visited=178215,backtracked=286508,end=10\nsearch:             maxDepth=930,constraints=16485\nchoice generators:  thread=96595 (signal=0,lock=7562,sharedRef=79295,threadApi=6790,reschedule=466), data=0\nheap:               new=92892,released=1468989,maxLive=851,gcCycles=257007\ninstructions:       33303633\nmax memory:         1019MB\nloaded code:        classes=157,methods=2690\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            60.99,
            59.45,
            56.87
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> locations) {\n        this.locations = new ConcurrentHashMap<>(locations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such vehicle: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n        \n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                SafePoint point = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"Thread 1 - Vehicle1 position: \" + point.get()[0] + \", \" + point.get()[1]);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                SafePoint point = tracker.getLocation(\"vehicle2\");\n                System.out.println(\"Thread 2 - Vehicle2 position: \" + point.get()[0] + \", \" + point.get()[1]);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        Thread.sleep(200);\n        \n        Map<String, SafePoint> allLocations = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : allLocations.entrySet()) {\n            int[] coords = entry.getValue().get();\n            System.out.println(\"Main thread - \" + entry.getKey() + \": \" + coords[0] + \", \" + coords[1]);\n        }\n        \n        try {\n            tracker.setLocation(\"nonexistent\", 0, 0);\n        } catch (IllegalArgumentException e) {\n            System.out.println(\"Exception caught: \" + e.getMessage());\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"Vehicle not found: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> snapshot = tracker.getLocations();\n        snapshot.forEach((id, point) -> {\n            int[] coords = point.get();\n            System.out.println(id + \": [\" + coords[0] + \", \" + coords[1] + \"]\");\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(2, TimeUnit.SECONDS);\n\n        System.out.println(\"\\nFinal positions:\");\n        tracker.getLocations().forEach((id, point) -> {\n            int[] coords = point.get();\n            System.out.println(id + \": [\" + coords[0] + \", \" + coords[1] + \"]\");\n        });\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such vehicle: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 10));\n        initialLocations.put(\"vehicle3\", new SafePoint(20, 20));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> snapshot = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : snapshot.entrySet()) {\n            SafePoint point = entry.getValue();\n            System.out.println(entry.getKey() + \": [\" + point.get()[0] + \", \" + point.get()[1] + \"]\");\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Vehicle tracker that safely publishes underlying state. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called PublishingVehicleTracker that coordinates the whereabouts of vehicles in a thread-safe manner. The class should allow safe publication of its internal state to prevent unintended adjustments from external code. Use a thread-safe map implementation to store vehicle whereabouts, where each entry maps a vehicle ID (String) to a SafePoint object that represents its current coordinates. Provide an unmodifiable view of the full whereabouts map for external access. Include methods to retrieve the full map of vehicle whereabouts, get the whereabouts of a specific vehicle by ID, and update the whereabouts of a vehicle by setting its x and y coordinates. Ensure that attempting to revise a non-existent vehicle raises an appropriate exception. The design should follow best practices for encapsulation and thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to handle tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using `java`. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> locations) {\n        this.locations = new ConcurrentHashMap<>(locations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such vehicle: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle3\", new SafePoint(30, 40));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                SafePoint point = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"Thread 1 - Vehicle1: \" + point);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 5, i * 15);\n                SafePoint point = tracker.getLocation(\"vehicle2\");\n                System.out.println(\"Thread 2 - Vehicle2: \" + point);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        Map<String, SafePoint> allLocations = tracker.getLocations();\n        System.out.println(\"Main thread - All locations: \" + allLocations);\n\n        try {\n            tracker.setLocation(\"nonexistent\", 0, 0);\n        } catch (IllegalArgumentException e) {\n            System.out.println(\"Exception caught: \" + e.getMessage());\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(2, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[] {x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public synchronized String toString() {\n        return \"[\" + x + \", \" + y + \"]\";\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle3\", new SafePoint(30, 40));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                System.out.println(\"Thread 1 updated vehicle1 to: \" + tracker.getLocation(\"vehicle1\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 5, i * 7);\n                System.out.println(\"Thread 2 updated vehicle2 to: \" + tracker.getLocation(\"vehicle2\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        System.out.println(\"Main thread - All locations: \" + tracker.getLocations());\n\n        executor.shutdown();\n        executor.awaitTermination(2, TimeUnit.SECONDS);\n\n        System.out.println(\"Final locations:\");\n        for (Map.Entry<String, SafePoint> entry : tracker.getLocations().entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public String toString() {\n        int[] coords = get();\n        return \"[\" + coords[0] + \", \" + coords[1] + \"]\";\n    }\n}",
            "import java.util.Collections;\nimport java.util.Map;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass SafePoint {\n    private int x;\n    private int y;\n    \n    public SafePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public SafePoint(SafePoint point) {\n        this(point.x, point.y);\n    }\n    \n    public synchronized int getX() {\n        return x;\n    }\n    \n    public synchronized int getY() {\n        return y;\n    }\n    \n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public synchronized String toString() {\n        return \"SafePoint[x=\" + x + \", y=\" + y + \"]\";\n    }\n}\n\nclass PublishingVehicleTracker {\n    private final Map<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n    \n    public PublishingVehicleTracker(Map<String, SafePoint> locations) {\n        this.locations = new ConcurrentHashMap<>(locations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n    \n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n    \n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n    \n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        }\n        loc.set(x, y);\n    }\n}\n\npublic class VehicleTrackerApp {\n    public static void main(String[] args) {\n        Map<String, SafePoint> initialLocations = new ConcurrentHashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle3\", new SafePoint(30, 40));\n        \n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                System.out.println(\"Thread 1 updated vehicle1 to: \" + tracker.getLocation(\"vehicle1\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 5, i * 7);\n                System.out.println(\"Thread 2 updated vehicle2 to: \" + tracker.getLocation(\"vehicle2\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(200);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Main thread - All vehicles: \");\n        Map<String, SafePoint> allLocations = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : allLocations.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n        \n        try {\n            tracker.setLocation(\"nonexistent\", 0, 0);\n        } catch (IllegalArgumentException e) {\n            System.out.println(\"Exception caught: \" + e.getMessage());\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\nprivate final Map<String, SafePoint> locations;\nprivate final Map<String, SafePoint> unmodifiableMap;\n\npublic PublishingVehicleTracker(Map<String, SafePoint> locations) {\nthis.locations = new ConcurrentHashMap<>(locations);\nthis.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n}\n\npublic Map<String, SafePoint> getLocations() {\nreturn unmodifiableMap;\n}\n\npublic SafePoint getLocation(String id) {\nreturn locations.get(id);\n}\n\npublic void setLocation(String id, int x, int y) {\nif (!locations.containsKey(id))\nthrow new IllegalArgumentException(\"invalid vehicle name: \" + id);\nlocations.get(id).set(x, y);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, SafePoint> initialPoints = new HashMap<>();\ninitialPoints.put(\"V1\", new SafePoint(0, 0));\ninitialPoints.put(\"V2\", new SafePoint(10, 10));\ninitialPoints.put(\"V3\", new SafePoint(20, 20));\n\nPublishingVehicleTracker tracker = new PublishingVehicleTracker(initialPoints);\n\nThread[] threads = new Thread[2]; // fewer threads for faster JPF testing\n\nfor (int i = 0; i < 2; i++) {\nfinal int taskId = i;\nthreads[i] = new Thread(() -> {\nRandom rand = new Random();\nfor (int j = 0; j < 3; j++) { // fewer iterations\nString vehicleId = \"V\" + ((taskId % 3) + 1);\nint newX = rand.nextInt(6); // 0 to 5\nint newY = rand.nextInt(6); // 0 to 5\ntracker.setLocation(vehicleId, newX, newY);\nSystem.out.println(Thread.currentThread().getName() +\n\" updated \" + vehicleId + \" to (\" + newX + \", \" + newY + \")\");\ntry {\nThread.sleep(20); // shorter sleep\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\ntracker.getLocations().forEach((id, point) ->\nSystem.out.println(id + \": (\" + point.getX() + \", \" + point.getY() + \")\"));\n}\n}\n\nclass SafePoint {\nprivate int x, y;\n\npublic SafePoint(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\npublic SafePoint(SafePoint point) {\nthis(point.getX(), point.getY());\n}\n\npublic synchronized int getX() {\nreturn x;\n}\n\npublic synchronized int getY() {\nreturn y;\n}\n\npublic synchronized void set(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n}",
        "max_depth": "93",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.44%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=119816,visited=169650,backtracked=288547,end=0\nsearch:             maxDepth=930,constraints=28302\nchoice generators:  thread=97099 (signal=0,lock=7684,sharedRef=81809,threadApi=2802,reschedule=26), data=0\nheap:               new=154031,released=1432712,maxLive=854,gcCycles=264220\ninstructions:       31794842\nmax memory:         1020MB\nloaded code:        classes=152,methods=2644\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.08%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.41%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.41%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=108182,visited=147212,backtracked=254490,end=0\nsearch:             maxDepth=930,constraints=27752\nchoice generators:  thread=85723 (signal=0,lock=6573,sharedRef=71963,threadApi=2341,reschedule=14), data=0\nheap:               new=1136281,released=129904,maxLive=859,gcCycles=233720\ninstructions:       32231979\nmax memory:         1019MB\nloaded code:        classes=157,methods=2691\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.42%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.43%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=105893,visited=170953,backtracked=275929,end=0\nsearch:             maxDepth=930,constraints=17191\nchoice generators:  thread=92877 (signal=0,lock=7866,sharedRef=79641,threadApi=2880,reschedule=21), data=0\nheap:               new=169732,released=1646828,maxLive=889,gcCycles=250956\ninstructions:       31875697\nmax memory:         1019MB\nloaded code:        classes=159,methods=2703\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            59.72,
            56.56,
            60.34
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> locations) {\n        this.locations = new ConcurrentHashMap<>(locations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such vehicle: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle3\", new SafePoint(30, 40));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                SafePoint point = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"Thread 1 - Vehicle1: \" + point);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 5, i * 15);\n                SafePoint point = tracker.getLocation(\"vehicle2\");\n                System.out.println(\"Thread 2 - Vehicle2: \" + point);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        Map<String, SafePoint> allLocations = tracker.getLocations();\n        System.out.println(\"Main thread - All locations: \" + allLocations);\n\n        try {\n            tracker.setLocation(\"nonexistent\", 0, 0);\n        } catch (IllegalArgumentException e) {\n            System.out.println(\"Exception caught: \" + e.getMessage());\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(2, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[] {x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public synchronized String toString() {\n        return \"[\" + x + \", \" + y + \"]\";\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        }\n        loc.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle3\", new SafePoint(30, 40));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                System.out.println(\"Thread 1 updated vehicle1 to: \" + tracker.getLocation(\"vehicle1\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 5, i * 7);\n                System.out.println(\"Thread 2 updated vehicle2 to: \" + tracker.getLocation(\"vehicle2\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        System.out.println(\"Main thread - All locations: \" + tracker.getLocations());\n\n        executor.shutdown();\n        executor.awaitTermination(2, TimeUnit.SECONDS);\n\n        System.out.println(\"Final locations:\");\n        for (Map.Entry<String, SafePoint> entry : tracker.getLocations().entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass SafePoint {\n    private int x, y;\n\n    public SafePoint(int x, int y) {\n        this.set(x, y);\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n\n    public SafePoint(int[] a) {\n        this(a[0], a[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public String toString() {\n        int[] coords = get();\n        return \"[\" + coords[0] + \", \" + coords[1] + \"]\";\n    }\n}\n```",
            "```java\nimport java.util.Collections;\nimport java.util.Map;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass SafePoint {\n    private int x;\n    private int y;\n    \n    public SafePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public SafePoint(SafePoint point) {\n        this(point.x, point.y);\n    }\n    \n    public synchronized int getX() {\n        return x;\n    }\n    \n    public synchronized int getY() {\n        return y;\n    }\n    \n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public synchronized String toString() {\n        return \"SafePoint[x=\" + x + \", y=\" + y + \"]\";\n    }\n}\n\nclass PublishingVehicleTracker {\n    private final Map<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n    \n    public PublishingVehicleTracker(Map<String, SafePoint> locations) {\n        this.locations = new ConcurrentHashMap<>(locations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n    \n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n    \n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n    \n    public void setLocation(String id, int x, int y) {\n        SafePoint loc = locations.get(id);\n        if (loc == null) {\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        }\n        loc.set(x, y);\n    }\n}\n\npublic class VehicleTrackerApp {\n    public static void main(String[] args) {\n        Map<String, SafePoint> initialLocations = new ConcurrentHashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle3\", new SafePoint(30, 40));\n        \n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                System.out.println(\"Thread 1 updated vehicle1 to: \" + tracker.getLocation(\"vehicle1\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 5, i * 7);\n                System.out.println(\"Thread 2 updated vehicle2 to: \" + tracker.getLocation(\"vehicle2\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(200);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Main thread - All vehicles: \");\n        Map<String, SafePoint> allLocations = tracker.getLocations();\n        for (Map.Entry<String, SafePoint> entry : allLocations.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n        \n        try {\n            tracker.setLocation(\"nonexistent\", 0, 0);\n        } catch (IllegalArgumentException e) {\n            System.out.println(\"Exception caught: \" + e.getMessage());\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Publishing an object. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named Prophecies that contains a static Set of objects of type Prophecy. This set should be awakened with a new instance of HashSet in a method called awaken(). Also, define an empty class named Prophecy. The goal is for the whispered Prophecies set to be accessible universally through the Prophecies class and be able to harbor multiple instances of the Prophecy class. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Prophecies {\n    private static volatile Set<Prophecy> prophecies;\n    \n    public static synchronized void awaken() {\n        prophecies = new HashSet<>();\n    }\n    \n    public static synchronized Set<Prophecy> getProphecies() {\n        return prophecies;\n    }\n    \n    public static synchronized void addProphecy(Prophecy prophecy) {\n        if (prophecies != null) {\n            prophecies.add(prophecy);\n        }\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> awakenTask = executor.submit(() -> {\n            Prophecies.awaken();\n            return null;\n        });\n        \n        awakenTask.get();\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Prophecies.addProphecy(new Prophecy());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Prophecies.addProphecy(new Prophecy());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Prophecies count: \" + Prophecies.getProphecies().size());\n        \n        executor.shutdown();\n    }\n}\n\nclass Prophecy {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Prophecies {\n    private static volatile Set<Prophecy> prophecies;\n    \n    public static synchronized void awaken() {\n        prophecies = new HashSet<>();\n    }\n    \n    public static synchronized void addProphecy(Prophecy p) {\n        if (prophecies != null) {\n            prophecies.add(p);\n        }\n    }\n    \n    public static synchronized Set<Prophecy> getProphecies() {\n        return prophecies != null ? new HashSet<>(prophecies) : null;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> awakenTask = executor.submit(() -> {\n            Prophecies.awaken();\n            return null;\n        });\n        \n        awakenTask.get();\n        \n        Future<Void> addTask1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Prophecies.addProphecy(new Prophecy());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> addTask2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Prophecies.addProphecy(new Prophecy());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        addTask1.get();\n        addTask2.get();\n        \n        System.out.println(\"Prophecies count: \" + Prophecies.getProphecies().size());\n        \n        executor.shutdown();\n    }\n}\n\nclass Prophecy {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Prophecies {\n    private static volatile Set<Prophecy> prophecies;\n    \n    public static void awaken() {\n        prophecies = new HashSet<>();\n    }\n    \n    public static Set<Prophecy> getProphecies() {\n        return prophecies;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> awakenTask = executor.submit(() -> {\n            awaken();\n            System.out.println(\"Prophecies awakened by thread: \" + Thread.currentThread().getName());\n        });\n        \n        awakenTask.get();\n        \n        Future<?> addTask = executor.submit(() -> {\n            Set<Prophecy> set = getProphecies();\n            synchronized(set) {\n                set.add(new Prophecy());\n                set.add(new Prophecy());\n                set.add(new Prophecy());\n            }\n            System.out.println(\"Added prophecies by thread: \" + Thread.currentThread().getName());\n        });\n        \n        Future<?> readTask = executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            Set<Prophecy> set = getProphecies();\n            synchronized(set) {\n                System.out.println(\"Prophecies count: \" + set.size() + \" by thread: \" + Thread.currentThread().getName());\n            }\n        });\n        \n        addTask.get();\n        readTask.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass Prophecy {\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ConcurrentHashMap;\n\nclass Secrets {\nprivate static final Set<Secret> knownSecrets = ConcurrentHashMap.newKeySet();\n\npublic static Set<Secret> getKnownSecrets() {\nreturn knownSecrets;\n}\n}\n\nclass Secret {\nprivate final String content;\n\npublic Secret(String content) {\nthis.content = content;\n}\n\n@Override\npublic String toString() {\nreturn \"Secret{\" +\n\"content='\" + content + '\\'' +\n'}';\n}\n}\n\npublic class SecretsMain {\n\npublic static void main(String[] args) throws InterruptedException {\nThread t1 = new Thread(() -> {\nSecret secret = new Secret(\"secret-1\");\nSecrets.getKnownSecrets().add(secret);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + secret);\n});\n\nThread t2 = new Thread(() -> {\nSecret secret = new Secret(\"secret-2\");\nSecrets.getKnownSecrets().add(secret);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + secret);\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All secrets:\");\nfor (Secret secret : Secrets.getKnownSecrets()) {\nSystem.out.println(secret);\n}\n\nSystem.out.println(\"Program finished.\");\n}\n}",
        "max_depth": "55",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 58.59%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 60.72%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 59.49%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=142415,visited=237624,backtracked=379962,end=500\nsearch:             maxDepth=210,constraints=0\nchoice generators:  thread=142402 (signal=0,lock=7871,sharedRef=107897,threadApi=5309,reschedule=3757), data=0\nheap:               new=132867,released=112617,maxLive=753,gcCycles=345932\ninstructions:       18439787\nmax memory:         1021MB\nloaded code:        classes=141,methods=2447\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 58.70%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 59.38%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 58.31%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=133060,visited=214994,backtracked=347902,end=428\nsearch:             maxDepth=244,constraints=0\nchoice generators:  thread=133047 (signal=0,lock=10694,sharedRef=89390,threadApi=2090,reschedule=6448), data=0\nheap:               new=179952,released=196094,maxLive=765,gcCycles=333750\ninstructions:       28557223\nmax memory:         1019MB\nloaded code:        classes=141,methods=2447\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 30.07%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 24.25%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 27.26%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=122916,visited=69946,backtracked=192328,end=46937\nsearch:             maxDepth=550,constraints=10900\nchoice generators:  thread=115033 (signal=0,lock=7,sharedRef=5188,threadApi=3,reschedule=62920), data=0\nheap:               new=537506,released=2522479,maxLive=753,gcCycles=192860\ninstructions:       93380074\nmax memory:         1015MB\nloaded code:        classes=142,methods=2448\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            50.0,
            48.97,
            48.29
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Prophecies {\n    private static volatile Set<Prophecy> prophecies;\n    \n    public static synchronized void awaken() {\n        prophecies = new HashSet<>();\n    }\n    \n    public static synchronized Set<Prophecy> getProphecies() {\n        return prophecies;\n    }\n    \n    public static synchronized void addProphecy(Prophecy prophecy) {\n        if (prophecies != null) {\n            prophecies.add(prophecy);\n        }\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> awakenTask = executor.submit(() -> {\n            Prophecies.awaken();\n            return null;\n        });\n        \n        awakenTask.get();\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Prophecies.addProphecy(new Prophecy());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Prophecies.addProphecy(new Prophecy());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Prophecies count: \" + Prophecies.getProphecies().size());\n        \n        executor.shutdown();\n    }\n}\n\nclass Prophecy {\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Prophecies {\n    private static volatile Set<Prophecy> prophecies;\n    \n    public static synchronized void awaken() {\n        prophecies = new HashSet<>();\n    }\n    \n    public static synchronized void addProphecy(Prophecy p) {\n        if (prophecies != null) {\n            prophecies.add(p);\n        }\n    }\n    \n    public static synchronized Set<Prophecy> getProphecies() {\n        return prophecies != null ? new HashSet<>(prophecies) : null;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> awakenTask = executor.submit(() -> {\n            Prophecies.awaken();\n            return null;\n        });\n        \n        awakenTask.get();\n        \n        Future<Void> addTask1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Prophecies.addProphecy(new Prophecy());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> addTask2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Prophecies.addProphecy(new Prophecy());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        addTask1.get();\n        addTask2.get();\n        \n        System.out.println(\"Prophecies count: \" + Prophecies.getProphecies().size());\n        \n        executor.shutdown();\n    }\n}\n\nclass Prophecy {\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Prophecies {\n    private static volatile Set<Prophecy> prophecies;\n    \n    public static void awaken() {\n        prophecies = new HashSet<>();\n    }\n    \n    public static Set<Prophecy> getProphecies() {\n        return prophecies;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> awakenTask = executor.submit(() -> {\n            awaken();\n            System.out.println(\"Prophecies awakened by thread: \" + Thread.currentThread().getName());\n        });\n        \n        awakenTask.get();\n        \n        Future<?> addTask = executor.submit(() -> {\n            Set<Prophecy> set = getProphecies();\n            synchronized(set) {\n                set.add(new Prophecy());\n                set.add(new Prophecy());\n                set.add(new Prophecy());\n            }\n            System.out.println(\"Added prophecies by thread: \" + Thread.currentThread().getName());\n        });\n        \n        Future<?> readTask = executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            Set<Prophecy> set = getProphecies();\n            synchronized(set) {\n                System.out.println(\"Prophecies count: \" + set.size() + \" by thread: \" + Thread.currentThread().getName());\n            }\n        });\n        \n        addTask.get();\n        readTask.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass Prophecy {\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Publishing an object. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named Galaxies that contains a static Set of objects of type Nebula. This set should be illuminated with a new instance of HashSet in a method called awaken(). Also, define an empty class named Nebula. The goal is for the whisperingNebulas set to be summoned universally through the Galaxies class and be able to crystallize multiple instances of the Nebula class. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Galaxies {\n    private static volatile Set<Nebula> whisperingNebulas;\n    \n    public static synchronized void awaken() {\n        whisperingNebulas = new HashSet<>();\n    }\n    \n    public static synchronized void crystallize(Nebula nebula) {\n        if (whisperingNebulas != null) {\n            whisperingNebulas.add(nebula);\n        }\n    }\n    \n    public static synchronized Set<Nebula> getWhisperingNebulas() {\n        return whisperingNebulas != null ? new HashSet<>(whisperingNebulas) : null;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            Galaxies.awaken();\n            for (int i = 0; i < 5; i++) {\n                Galaxies.crystallize(new Nebula());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 5; i++) {\n                Galaxies.crystallize(new Nebula());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Total Nebulas: \" + Galaxies.getWhisperingNebulas().size());\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass Nebula {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Galaxies {\n    private static volatile Set<Nebula> whisperingNebulas;\n    \n    public static synchronized void awaken() {\n        whisperingNebulas = new HashSet<>();\n    }\n    \n    public static synchronized void crystallize(Nebula nebula) {\n        if (whisperingNebulas != null) {\n            whisperingNebulas.add(nebula);\n        }\n    }\n    \n    public static synchronized Set<Nebula> getWhisperingNebulas() {\n        return whisperingNebulas != null ? new HashSet<>(whisperingNebulas) : null;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> awakening = executor.submit(() -> {\n            Galaxies.awaken();\n            return null;\n        });\n        \n        awakening.get();\n        \n        Future<Void> crystallization1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Galaxies.crystallize(new Nebula());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> crystallization2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Galaxies.crystallize(new Nebula());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        crystallization1.get();\n        crystallization2.get();\n        \n        Set<Nebula> nebulas = Galaxies.getWhisperingNebulas();\n        System.out.println(\"Total nebulas crystallized: \" + (nebulas != null ? nebulas.size() : 0));\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass Nebula {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Galaxies {\n    private static volatile Set<Nebula> whisperingNebulas;\n    \n    public static synchronized void awaken() {\n        whisperingNebulas = new HashSet<>();\n    }\n    \n    public static synchronized void crystallize(Nebula nebula) {\n        if (whisperingNebulas != null) {\n            whisperingNebulas.add(nebula);\n        }\n    }\n    \n    public static synchronized Set<Nebula> getWhisperingNebulas() {\n        return whisperingNebulas != null ? new HashSet<>(whisperingNebulas) : null;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> awakenTask = executor.submit(() -> {\n            Galaxies.awaken();\n            System.out.println(\"Galaxies awakened by thread: \" + Thread.currentThread().getName());\n        });\n        \n        awakenTask.get();\n        \n        Future<?> crystallizeTask1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Nebula nebula = new Nebula();\n                Galaxies.crystallize(nebula);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \" crystallized nebula \" + i);\n            }\n        });\n        \n        Future<?> crystallizeTask2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Nebula nebula = new Nebula();\n                Galaxies.crystallize(nebula);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \" crystallized nebula \" + i);\n            }\n        });\n        \n        crystallizeTask1.get();\n        crystallizeTask2.get();\n        \n        Set<Nebula> nebulas = Galaxies.getWhisperingNebulas();\n        System.out.println(\"Total nebulas crystallized: \" + (nebulas != null ? nebulas.size() : 0));\n        \n        executor.shutdown();\n    }\n}\n\nclass Nebula {\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ConcurrentHashMap;\n\nclass Secrets {\nprivate static final Set<Secret> knownSecrets = ConcurrentHashMap.newKeySet();\n\npublic static Set<Secret> getKnownSecrets() {\nreturn knownSecrets;\n}\n}\n\nclass Secret {\nprivate final String content;\n\npublic Secret(String content) {\nthis.content = content;\n}\n\n@Override\npublic String toString() {\nreturn \"Secret{\" +\n\"content='\" + content + '\\'' +\n'}';\n}\n}\n\npublic class SecretsMain {\n\npublic static void main(String[] args) throws InterruptedException {\nThread t1 = new Thread(() -> {\nSecret secret = new Secret(\"secret-1\");\nSecrets.getKnownSecrets().add(secret);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + secret);\n});\n\nThread t2 = new Thread(() -> {\nSecret secret = new Secret(\"secret-2\");\nSecrets.getKnownSecrets().add(secret);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + secret);\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All secrets:\");\nfor (Secret secret : Secrets.getKnownSecrets()) {\nSystem.out.println(secret);\n}\n\nSystem.out.println(\"Program finished.\");\n}\n}",
        "max_depth": "55",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 37.59%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 21.61%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 26.28%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=131160,visited=78897,backtracked=209588,end=54802\nsearch:             maxDepth=550,constraints=4308\nchoice generators:  thread=128167 (signal=0,lock=11,sharedRef=51816,threadApi=7,reschedule=67154), data=0\nheap:               new=483190,released=2644550,maxLive=759,gcCycles=210049\ninstructions:       89101106\nmax memory:         1016MB\nloaded code:        classes=141,methods=2445\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 30.20%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 23.27%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 25.65%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=124300,visited=67815,backtracked=191624,end=49229\nsearch:             maxDepth=550,constraints=10743\nchoice generators:  thread=116527 (signal=0,lock=10,sharedRef=3039,threadApi=7,reschedule=63097), data=0\nheap:               new=498816,released=3371540,maxLive=771,gcCycles=192108\ninstructions:       92219522\nmax memory:         1015MB\nloaded code:        classes=141,methods=2447\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 60.62%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 59.21%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 59.96%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=129760,visited=217748,backtracked=347371,end=191\nsearch:             maxDepth=238,constraints=0\nchoice generators:  thread=129756 (signal=0,lock=8409,sharedRef=99286,threadApi=1082,reschedule=5857), data=0\nheap:               new=254408,released=261637,maxLive=772,gcCycles=323730\ninstructions:       21355173\nmax memory:         1020MB\nloaded code:        classes=142,methods=2449\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            49.63,
            48.66,
            55.24
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Galaxies {\n    private static volatile Set<Nebula> whisperingNebulas;\n    \n    public static synchronized void awaken() {\n        whisperingNebulas = new HashSet<>();\n    }\n    \n    public static synchronized void crystallize(Nebula nebula) {\n        if (whisperingNebulas != null) {\n            whisperingNebulas.add(nebula);\n        }\n    }\n    \n    public static synchronized Set<Nebula> getWhisperingNebulas() {\n        return whisperingNebulas != null ? new HashSet<>(whisperingNebulas) : null;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            Galaxies.awaken();\n            for (int i = 0; i < 5; i++) {\n                Galaxies.crystallize(new Nebula());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 5; i++) {\n                Galaxies.crystallize(new Nebula());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Total Nebulas: \" + Galaxies.getWhisperingNebulas().size());\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass Nebula {\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Galaxies {\n    private static volatile Set<Nebula> whisperingNebulas;\n    \n    public static synchronized void awaken() {\n        whisperingNebulas = new HashSet<>();\n    }\n    \n    public static synchronized void crystallize(Nebula nebula) {\n        if (whisperingNebulas != null) {\n            whisperingNebulas.add(nebula);\n        }\n    }\n    \n    public static synchronized Set<Nebula> getWhisperingNebulas() {\n        return whisperingNebulas != null ? new HashSet<>(whisperingNebulas) : null;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> awakening = executor.submit(() -> {\n            Galaxies.awaken();\n            return null;\n        });\n        \n        awakening.get();\n        \n        Future<Void> crystallization1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Galaxies.crystallize(new Nebula());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> crystallization2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Galaxies.crystallize(new Nebula());\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        crystallization1.get();\n        crystallization2.get();\n        \n        Set<Nebula> nebulas = Galaxies.getWhisperingNebulas();\n        System.out.println(\"Total nebulas crystallized: \" + (nebulas != null ? nebulas.size() : 0));\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n\nclass Nebula {\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Galaxies {\n    private static volatile Set<Nebula> whisperingNebulas;\n    \n    public static synchronized void awaken() {\n        whisperingNebulas = new HashSet<>();\n    }\n    \n    public static synchronized void crystallize(Nebula nebula) {\n        if (whisperingNebulas != null) {\n            whisperingNebulas.add(nebula);\n        }\n    }\n    \n    public static synchronized Set<Nebula> getWhisperingNebulas() {\n        return whisperingNebulas != null ? new HashSet<>(whisperingNebulas) : null;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> awakenTask = executor.submit(() -> {\n            Galaxies.awaken();\n            System.out.println(\"Galaxies awakened by thread: \" + Thread.currentThread().getName());\n        });\n        \n        awakenTask.get();\n        \n        Future<?> crystallizeTask1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Nebula nebula = new Nebula();\n                Galaxies.crystallize(nebula);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \" crystallized nebula \" + i);\n            }\n        });\n        \n        Future<?> crystallizeTask2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Nebula nebula = new Nebula();\n                Galaxies.crystallize(nebula);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \" crystallized nebula \" + i);\n            }\n        });\n        \n        crystallizeTask1.get();\n        crystallizeTask2.get();\n        \n        Set<Nebula> nebulas = Galaxies.getWhisperingNebulas();\n        System.out.println(\"Total nebulas crystallized: \" + (nebulas != null ? nebulas.size() : 0));\n        \n        executor.shutdown();\n    }\n}\n\nclass Nebula {\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Publishing an object. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named Cathedrals that contains a static Set of objects of type Phantom. This set should be conjured with a new instance of HashSet in a method called materialize(). Also, define an empty class named Phantom. The goal is for the driftingPhantoms set to be harvested eternally through the Cathedrals class and be able to capture multiple instances of the Phantom class. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Cathedrals {\n    private static Set<Phantom> driftingPhantoms;\n    \n    public static void materialize() {\n        driftingPhantoms = new HashSet<>();\n    }\n    \n    public static synchronized void addPhantom(Phantom phantom) {\n        if (driftingPhantoms != null) {\n            driftingPhantoms.add(phantom);\n        }\n    }\n    \n    public static synchronized Set<Phantom> getPhantoms() {\n        return driftingPhantoms != null ? new HashSet<>(driftingPhantoms) : new HashSet<>();\n    }\n    \n    public static void main(String[] args) {\n        materialize();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                addPhantom(new Phantom());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                Set<Phantom> phantoms = getPhantoms();\n                System.out.println(\"Harvested \" + phantoms.size() + \" phantoms\");\n                try {\n                    Thread.sleep(500);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(5000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdownNow();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass Phantom {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Cathedrals {\n    private static Set<Phantom> driftingPhantoms;\n    \n    public static synchronized void materialize() {\n        driftingPhantoms = new HashSet<>();\n    }\n    \n    public static synchronized void addPhantom(Phantom phantom) {\n        if (driftingPhantoms != null) {\n            driftingPhantoms.add(phantom);\n        }\n    }\n    \n    public static synchronized Set<Phantom> getPhantoms() {\n        return driftingPhantoms != null ? new HashSet<>(driftingPhantoms) : new HashSet<>();\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        materialize();\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                try {\n                    Phantom phantom = new Phantom();\n                    addPhantom(phantom);\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                try {\n                    Set<Phantom> currentPhantoms = getPhantoms();\n                    System.out.println(\"Harvested phantoms: \" + currentPhantoms.size());\n                    Thread.sleep(500);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(5000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdownNow();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass Phantom {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Cathedrals {\n    private static Set<Phantom> driftingPhantoms;\n    \n    public static void materialize() {\n        driftingPhantoms = new HashSet<>();\n    }\n    \n    public static synchronized void addPhantom(Phantom phantom) {\n        if (driftingPhantoms != null) {\n            driftingPhantoms.add(phantom);\n        }\n    }\n    \n    public static synchronized Set<Phantom> getPhantoms() {\n        return driftingPhantoms != null ? new HashSet<>(driftingPhantoms) : new HashSet<>();\n    }\n    \n    public static void main(String[] args) {\n        materialize();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                addPhantom(new Phantom());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                Set<Phantom> phantoms = getPhantoms();\n                System.out.println(\"Harvested \" + phantoms.size() + \" phantoms\");\n                try {\n                    Thread.sleep(500);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(5000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdownNow();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass Phantom {\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ConcurrentHashMap;\n\nclass Secrets {\nprivate static final Set<Secret> knownSecrets = ConcurrentHashMap.newKeySet();\n\npublic static Set<Secret> getKnownSecrets() {\nreturn knownSecrets;\n}\n}\n\nclass Secret {\nprivate final String content;\n\npublic Secret(String content) {\nthis.content = content;\n}\n\n@Override\npublic String toString() {\nreturn \"Secret{\" +\n\"content='\" + content + '\\'' +\n'}';\n}\n}\n\npublic class SecretsMain {\n\npublic static void main(String[] args) throws InterruptedException {\nThread t1 = new Thread(() -> {\nSecret secret = new Secret(\"secret-1\");\nSecrets.getKnownSecrets().add(secret);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + secret);\n});\n\nThread t2 = new Thread(() -> {\nSecret secret = new Secret(\"secret-2\");\nSecrets.getKnownSecrets().add(secret);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + secret);\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All secrets:\");\nfor (Secret secret : Secrets.getKnownSecrets()) {\nSystem.out.println(secret);\n}\n\nSystem.out.println(\"Program finished.\");\n}\n}",
        "max_depth": "55",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.82%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.22%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.23%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=111247,visited=186682,backtracked=297761,end=388\nsearch:             maxDepth=550,constraints=9078\nchoice generators:  thread=103477 (signal=0,lock=5,sharedRef=89429,threadApi=3,reschedule=11775), data=0\nheap:               new=121509,released=817118,maxLive=728,gcCycles=297929\ninstructions:       53710733\nmax memory:         1019MB\nloaded code:        classes=137,methods=2462\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.81%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.23%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.24%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=110783,visited=184673,backtracked=295287,end=383\nsearch:             maxDepth=550,constraints=9552\nchoice generators:  thread=102608 (signal=0,lock=5,sharedRef=88598,threadApi=3,reschedule=11640), data=0\nheap:               new=120122,released=807714,maxLive=728,gcCycles=295456\ninstructions:       53124935\nmax memory:         1019MB\nloaded code:        classes=137,methods=2462\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.81%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.23%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.23%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=111045,visited=185622,backtracked=296501,end=385\nsearch:             maxDepth=550,constraints=9373\nchoice generators:  thread=103031 (signal=0,lock=5,sharedRef=88995,threadApi=3,reschedule=11704), data=0\nheap:               new=120769,released=812089,maxLive=728,gcCycles=296667\ninstructions:       53399242\nmax memory:         1019MB\nloaded code:        classes=137,methods=2462\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            44.37,
            45.03,
            44.37
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Cathedrals {\n    private static Set<Phantom> driftingPhantoms;\n    \n    public static void materialize() {\n        driftingPhantoms = new HashSet<>();\n    }\n    \n    public static synchronized void addPhantom(Phantom phantom) {\n        if (driftingPhantoms != null) {\n            driftingPhantoms.add(phantom);\n        }\n    }\n    \n    public static synchronized Set<Phantom> getPhantoms() {\n        return driftingPhantoms != null ? new HashSet<>(driftingPhantoms) : new HashSet<>();\n    }\n    \n    public static void main(String[] args) {\n        materialize();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                addPhantom(new Phantom());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                Set<Phantom> phantoms = getPhantoms();\n                System.out.println(\"Harvested \" + phantoms.size() + \" phantoms\");\n                try {\n                    Thread.sleep(500);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(5000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdownNow();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass Phantom {\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Cathedrals {\n    private static Set<Phantom> driftingPhantoms;\n    \n    public static synchronized void materialize() {\n        driftingPhantoms = new HashSet<>();\n    }\n    \n    public static synchronized void addPhantom(Phantom phantom) {\n        if (driftingPhantoms != null) {\n            driftingPhantoms.add(phantom);\n        }\n    }\n    \n    public static synchronized Set<Phantom> getPhantoms() {\n        return driftingPhantoms != null ? new HashSet<>(driftingPhantoms) : new HashSet<>();\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        materialize();\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                try {\n                    Phantom phantom = new Phantom();\n                    addPhantom(phantom);\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                try {\n                    Set<Phantom> currentPhantoms = getPhantoms();\n                    System.out.println(\"Harvested phantoms: \" + currentPhantoms.size());\n                    Thread.sleep(500);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(5000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdownNow();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass Phantom {\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class Cathedrals {\n    private static Set<Phantom> driftingPhantoms;\n    \n    public static void materialize() {\n        driftingPhantoms = new HashSet<>();\n    }\n    \n    public static synchronized void addPhantom(Phantom phantom) {\n        if (driftingPhantoms != null) {\n            driftingPhantoms.add(phantom);\n        }\n    }\n    \n    public static synchronized Set<Phantom> getPhantoms() {\n        return driftingPhantoms != null ? new HashSet<>(driftingPhantoms) : new HashSet<>();\n    }\n    \n    public static void main(String[] args) {\n        materialize();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                addPhantom(new Phantom());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            while (!Thread.currentThread().isInterrupted()) {\n                Set<Phantom> phantoms = getPhantoms();\n                System.out.println(\"Harvested \" + phantoms.size() + \" phantoms\");\n                try {\n                    Thread.sleep(500);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(5000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdownNow();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass Phantom {\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Thread confinement of local primitive and reference variables. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java program that models the process of inscribing runes onto a grimoire in harmonies. The program should define classes and enums representing runes, their constellation and resonance, and a mechanism for harmonizing runes based on constellation and resonance compatibility. Each rune has a constellation and resonance, and only runes of the same constellation and opposite resonances can form a harmony.\nThe main logic is implemented in a method called channelTheGrimoire, which takes a collection of candidate runes as input and returns the number of valid harmonies formed. Inside this method, runes are transmuted using a custom comparator that sequences them first by constellation and then by resonance. This ensures that runes of the same constellation and opposite resonances are woven together for harmonizing.\nAdditionally, implement a class to represent the grimoire that can crystallize these rune harmonies, and a helper class to represent each harmony of runes. Ensure proper encapsulation and thread confinement of variables within the method, preventing any unintended side effects or data sharing between threads. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.SOLAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        RuneChanneler channeler = new RuneChanneler();\n        int harmonies = channeler.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK;\n    \n    public boolean isOpposite(Resonance other) {\n        return this != other;\n    }\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n    \n    public boolean canHarmonizeWith(Rune other) {\n        return this.constellation == other.constellation && \n               this.resonance.isOpposite(other.resonance);\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> harmonies;\n    \n    public Grimoire() {\n        this.harmonies = new CopyOnWriteArrayList<>();\n    }\n    \n    public void crystallize(RuneHarmony harmony) {\n        harmonies.add(harmony);\n    }\n    \n    public List<RuneHarmony> getHarmonies() {\n        return new ArrayList<>(harmonies);\n    }\n    \n    public int getHarmonyCount() {\n        return harmonies.size();\n    }\n}\n\nclass RuneChanneler {\n    private final ExecutorService executor = Executors.newFixedThreadPool(2);\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        List<Rune> localRunes = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        localRunes.sort(runeComparator);\n        \n        Grimoire grimoire = new Grimoire();\n        \n        int midPoint = localRunes.size() / 2;\n        List<Rune> firstHalf = localRunes.subList(0, midPoint);\n        List<Rune> secondHalf = localRunes.subList(midPoint, localRunes.size());\n        \n        Future<Integer> task1 = executor.submit(() -> {\n            int count = 0;\n            for (int i = 0; i < firstHalf.size(); i++) {\n                for (int j = i + 1; j < localRunes.size(); j++) {\n                    Rune rune1 = firstHalf.get(i);\n                    Rune rune2 = localRunes.get(j);\n                    if (rune1.canHarmonizeWith(rune2)) {\n                        grimoire.crystallize(new RuneHarmony(rune1, rune2));\n                        count++;\n                    }\n                }\n            }\n            return count;\n        });\n        \n        Future<Integer> task2 = executor.submit(() -> {\n            int count = 0;\n            for (int i = 0; i < secondHalf.size(); i++) {\n                for (int j = i + 1; j < secondHalf.size(); j++) {\n                    Rune rune1 = secondHalf.get(i);\n                    Rune rune2 = secondHalf.get(j);\n                    if (rune1.canHarmonizeWith(rune2)) {\n                        grimoire.crystallize(new RuneHarmony(rune1, rune2));\n                        count++;\n                    }\n                }\n            }\n            return count;\n        });\n        \n        int result = task1.get() + task2.get();\n        executor.shutdown();\n        return result;\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK),\n            new Rune(Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(Constellation.LUNAR, Resonance.DARK),\n            new Rune(Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(Constellation.STELLAR, Resonance.DARK),\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n        \n        grimoire.crystallizeHarmonies();\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK;\n    \n    public boolean isOpposite(Resonance other) {\n        return this != other;\n    }\n}\n\nclass Rune {\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(Constellation constellation, Resonance resonance) {\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n    \n    public boolean canHarmonizeWith(Rune other) {\n        return this.constellation == other.constellation && \n               this.resonance.isOpposite(other.resonance);\n    }\n    \n    @Override\n    public String toString() {\n        return constellation + \"-\" + resonance;\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Harmony[\" + firstRune + \" + \" + secondRune + \"]\";\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> harmonies = Collections.synchronizedList(new ArrayList<>());\n    private final ExecutorService executor = Executors.newFixedThreadPool(2);\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        Collections.sort(transmutedRunes, runeComparator);\n        \n        Map<Constellation, List<Rune>> constellationGroups = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        List<Future<Integer>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : constellationGroups.entrySet()) {\n            futures.add(executor.submit(() -> {\n                int localHarmonies = 0;\n                List<Rune> runeGroup = new ArrayList<>(entry.getValue());\n                List<Rune> lightRunes = runeGroup.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                List<Rune> darkRunes = runeGroup.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int pairs = Math.min(lightRunes.size(), darkRunes.size());\n                \n                for (int i = 0; i < pairs; i++) {\n                    RuneHarmony harmony = new RuneHarmony(lightRunes.get(i), darkRunes.get(i));\n                    harmonies.add(harmony);\n                    localHarmonies++;\n                }\n                \n                return localHarmonies;\n            }));\n        }\n        \n        int totalHarmonies = 0;\n        for (Future<Integer> future : futures) {\n            totalHarmonies += future.get();\n        }\n        \n        return totalHarmonies;\n    }\n    \n    public void crystallizeHarmonies() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        synchronized (harmonies) {\n            System.out.println(\"Crystallized Harmonies:\");\n            for (RuneHarmony harmony : harmonies) {\n                System.out.println(harmony);\n            }\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.Collectors;\n\npublic class GrimoireInscription {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    STELLAR, LUNAR, SOLAR\n}\n\nenum Resonance {\n    LIGHT, DARK\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies = Collections.synchronizedList(new ArrayList<>());\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        transmutedRunes.sort(runeComparator);\n        \n        Map<Constellation, List<Rune>> runesByConstellation = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        List<Future<Integer>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            Future<Integer> future = executor.submit(() -> {\n                List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                List<Rune> lightRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                List<Rune> darkRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int localHarmonies = 0;\n                int minSize = Math.min(lightRunes.size(), darkRunes.size());\n                \n                for (int i = 0; i < minSize; i++) {\n                    RuneHarmony harmony = new RuneHarmony(lightRunes.get(i), darkRunes.get(i));\n                    crystallizeHarmony(harmony);\n                    localHarmonies++;\n                }\n                \n                return localHarmonies;\n            });\n            futures.add(future);\n        }\n        \n        int totalHarmonies = 0;\n        for (Future<Integer> future : futures) {\n            totalHarmonies += future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        return totalHarmonies;\n    }\n    \n    private void crystallizeHarmony(RuneHarmony harmony) {\n        crystallizedHarmonies.add(harmony);\n    }\n    \n    public List<RuneHarmony> getCrystallizedHarmonies() {\n        return new ArrayList<>(crystallizedHarmonies);\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class Animals {\nprivate final Ark ark;\n\npublic Animals() {\nthis.ark = new Ark();\n}\n\npublic int loadTheArk(Collection<Animal> candidates) {\nSortedSet<Animal> animals;\nint numPairs = 0;\nAnimal candidate = null;\n\nanimals = new TreeSet<>(new SpeciesGenderComparator());\nanimals.addAll(candidates);\nfor (Animal a : animals) {\nif (candidate == null || !candidate.isPotentialMate(a)) {\ncandidate = a;\n} else {\nark.load(new AnimalPair(candidate, a));\n++numPairs;\ncandidate = null;\n}\n}\nreturn numPairs;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nAnimals animalsApp = new Animals();\n\nCollection<Animal> group1 = createSampleAnimals(4);\nCollection<Animal> group2 = createSampleAnimals(4);\n\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nexecutor.submit(() -> {\nint pairs = animalsApp.loadTheArk(group1);\nSystem.out.println(Thread.currentThread().getName() + \" loaded \" + pairs + \" pairs.\");\n});\n\nexecutor.submit(() -> {\nint pairs = animalsApp.loadTheArk(group2);\nSystem.out.println(Thread.currentThread().getName() + \" loaded \" + pairs + \" pairs.\");\n});\n\nexecutor.shutdown();\n}\n\nprivate static Collection<Animal> createSampleAnimals(int count) {\nList<Animal> list = new ArrayList<>();\nRandom rand = new Random();\nSpecies[] speciesArray = Species.values();\nGender[] genders = Gender.values();\n\nfor (int i = 0; i < count; i++) {\nAnimal animal = new Animal();\nanimal.species = speciesArray[rand.nextInt(speciesArray.length)];\nanimal.gender = genders[rand.nextInt(genders.length)];\nlist.add(animal);\n}\n\nreturn list;\n}\n\nstatic class Animal {\nSpecies species;\nGender gender;\n\npublic boolean isPotentialMate(Animal other) {\nreturn species == other.species && gender != other.gender;\n}\n}\n\nenum Species {\nAARDVARK, BENGAL_TIGER, CARIBOU, DINGO\n}\n\nenum Gender {\nMALE, FEMALE\n}\n\nstatic class AnimalPair {\nprivate final Animal one, two;\n\npublic AnimalPair(Animal one, Animal two) {\nthis.one = one;\nthis.two = two;\n}\n}\n\nstatic class SpeciesGenderComparator implements Comparator<Animal> {\npublic int compare(Animal one, Animal two) {\nint speciesCompare = one.species.compareTo(two.species);\nreturn (speciesCompare != 0)\n? speciesCompare\n: one.gender.compareTo(two.gender);\n}\n}\n\nstatic class Ark {\nprivate final Set<AnimalPair> loadedAnimals = Collections.synchronizedSet(new HashSet<>());\n\npublic void load(AnimalPair pair) {\nloadedAnimals.add(pair);\nSystem.out.println(Thread.currentThread().getName() + \" loaded a pair: \" + pair.hashCode());\n}\n}\n}",
        "max_depth": "133",
        "jpf_details": [
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=762,released=0,maxLive=0,gcCycles=0\ninstructions:       7635\nmax memory:         981MB\nloaded code:        classes=135,methods=2616\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=754,released=0,maxLive=0,gcCycles=0\ninstructions:       7661\nmax memory:         981MB\nloaded code:        classes=137,methods=2639\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=770,released=0,maxLive=0,gcCycles=0\ninstructions:       7692\nmax memory:         981MB\nloaded code:        classes=137,methods=2638\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\""
        ],
        "codebleu_score": [
            55.48,
            56.18,
            54.04
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.SOLAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        RuneChanneler channeler = new RuneChanneler();\n        int harmonies = channeler.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK;\n    \n    public boolean isOpposite(Resonance other) {\n        return this != other;\n    }\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n    \n    public boolean canHarmonizeWith(Rune other) {\n        return this.constellation == other.constellation && \n               this.resonance.isOpposite(other.resonance);\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> harmonies;\n    \n    public Grimoire() {\n        this.harmonies = new CopyOnWriteArrayList<>();\n    }\n    \n    public void crystallize(RuneHarmony harmony) {\n        harmonies.add(harmony);\n    }\n    \n    public List<RuneHarmony> getHarmonies() {\n        return new ArrayList<>(harmonies);\n    }\n    \n    public int getHarmonyCount() {\n        return harmonies.size();\n    }\n}\n\nclass RuneChanneler {\n    private final ExecutorService executor = Executors.newFixedThreadPool(2);\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        List<Rune> localRunes = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        localRunes.sort(runeComparator);\n        \n        Grimoire grimoire = new Grimoire();\n        \n        int midPoint = localRunes.size() / 2;\n        List<Rune> firstHalf = localRunes.subList(0, midPoint);\n        List<Rune> secondHalf = localRunes.subList(midPoint, localRunes.size());\n        \n        Future<Integer> task1 = executor.submit(() -> {\n            int count = 0;\n            for (int i = 0; i < firstHalf.size(); i++) {\n                for (int j = i + 1; j < localRunes.size(); j++) {\n                    Rune rune1 = firstHalf.get(i);\n                    Rune rune2 = localRunes.get(j);\n                    if (rune1.canHarmonizeWith(rune2)) {\n                        grimoire.crystallize(new RuneHarmony(rune1, rune2));\n                        count++;\n                    }\n                }\n            }\n            return count;\n        });\n        \n        Future<Integer> task2 = executor.submit(() -> {\n            int count = 0;\n            for (int i = 0; i < secondHalf.size(); i++) {\n                for (int j = i + 1; j < secondHalf.size(); j++) {\n                    Rune rune1 = secondHalf.get(i);\n                    Rune rune2 = secondHalf.get(j);\n                    if (rune1.canHarmonizeWith(rune2)) {\n                        grimoire.crystallize(new RuneHarmony(rune1, rune2));\n                        count++;\n                    }\n                }\n            }\n            return count;\n        });\n        \n        int result = task1.get() + task2.get();\n        executor.shutdown();\n        return result;\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK),\n            new Rune(Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(Constellation.LUNAR, Resonance.DARK),\n            new Rune(Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(Constellation.STELLAR, Resonance.DARK),\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n        \n        grimoire.crystallizeHarmonies();\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK;\n    \n    public boolean isOpposite(Resonance other) {\n        return this != other;\n    }\n}\n\nclass Rune {\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(Constellation constellation, Resonance resonance) {\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n    \n    public boolean canHarmonizeWith(Rune other) {\n        return this.constellation == other.constellation && \n               this.resonance.isOpposite(other.resonance);\n    }\n    \n    @Override\n    public String toString() {\n        return constellation + \"-\" + resonance;\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Harmony[\" + firstRune + \" + \" + secondRune + \"]\";\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> harmonies = Collections.synchronizedList(new ArrayList<>());\n    private final ExecutorService executor = Executors.newFixedThreadPool(2);\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        Collections.sort(transmutedRunes, runeComparator);\n        \n        Map<Constellation, List<Rune>> constellationGroups = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        List<Future<Integer>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : constellationGroups.entrySet()) {\n            futures.add(executor.submit(() -> {\n                int localHarmonies = 0;\n                List<Rune> runeGroup = new ArrayList<>(entry.getValue());\n                List<Rune> lightRunes = runeGroup.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                List<Rune> darkRunes = runeGroup.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int pairs = Math.min(lightRunes.size(), darkRunes.size());\n                \n                for (int i = 0; i < pairs; i++) {\n                    RuneHarmony harmony = new RuneHarmony(lightRunes.get(i), darkRunes.get(i));\n                    harmonies.add(harmony);\n                    localHarmonies++;\n                }\n                \n                return localHarmonies;\n            }));\n        }\n        \n        int totalHarmonies = 0;\n        for (Future<Integer> future : futures) {\n            totalHarmonies += future.get();\n        }\n        \n        return totalHarmonies;\n    }\n    \n    public void crystallizeHarmonies() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        synchronized (harmonies) {\n            System.out.println(\"Crystallized Harmonies:\");\n            for (RuneHarmony harmony : harmonies) {\n                System.out.println(harmony);\n            }\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.Collectors;\n\npublic class GrimoireInscription {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    STELLAR, LUNAR, SOLAR\n}\n\nenum Resonance {\n    LIGHT, DARK\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies = Collections.synchronizedList(new ArrayList<>());\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        transmutedRunes.sort(runeComparator);\n        \n        Map<Constellation, List<Rune>> runesByConstellation = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        List<Future<Integer>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            Future<Integer> future = executor.submit(() -> {\n                List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                List<Rune> lightRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                List<Rune> darkRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int localHarmonies = 0;\n                int minSize = Math.min(lightRunes.size(), darkRunes.size());\n                \n                for (int i = 0; i < minSize; i++) {\n                    RuneHarmony harmony = new RuneHarmony(lightRunes.get(i), darkRunes.get(i));\n                    crystallizeHarmony(harmony);\n                    localHarmonies++;\n                }\n                \n                return localHarmonies;\n            });\n            futures.add(future);\n        }\n        \n        int totalHarmonies = 0;\n        for (Future<Integer> future : futures) {\n            totalHarmonies += future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        return totalHarmonies;\n    }\n    \n    private void crystallizeHarmony(RuneHarmony harmony) {\n        crystallizedHarmonies.add(harmony);\n    }\n    \n    public List<RuneHarmony> getCrystallizedHarmonies() {\n        return new ArrayList<>(crystallizedHarmonies);\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Thread confinement of local primitive and reference variables. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java program that models the process of inscribing runes onto a grimoire in harmonies. The program should define classes and enums representing runes, their constellation and resonance, and a mechanism for harmonizing runes based on constellation and resonance compatibility. Each rune has a constellation and resonance, and only runes of the same constellation and opposite resonances can form a harmony.\nThe main logic is implemented in a method called channelTheGrimoire, which takes a collection of candidate runes as input and returns the number of valid harmonies formed. Inside this method, runes are transmuted using a custom comparator that sequences them first by constellation and then by resonance. This ensures that runes of the same constellation and opposite resonances are woven together for harmonizing.\nAdditionally, implement a class to represent the grimoire that can crystallize these rune harmonies, and a helper class to represent each harmony of runes. Ensure proper encapsulation and thread confinement of variables within the method, preventing any unintended side effects or data sharing between threads. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.SOLAR, Resonance.SHADOW),\n            new Rune(\"Gamma\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.LUNAR, Resonance.SHADOW),\n            new Rune(\"Epsilon\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.SOLAR, Resonance.SHADOW),\n            new Rune(\"Eta\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.STELLAR, Resonance.SHADOW)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, SHADOW\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies;\n    private final ExecutorService executor;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new CopyOnWriteArrayList<>();\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) {\n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        transmutedRunes.sort(runeComparator);\n        \n        Map<Constellation, List<Rune>> runesByConstellation = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        CountDownLatch latch = new CountDownLatch(runesByConstellation.size());\n        List<Future<Integer>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            Future<Integer> future = executor.submit(() -> {\n                try {\n                    List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                    List<Rune> lightRunes = constellationRunes.stream()\n                        .filter(r -> r.getResonance() == Resonance.LIGHT)\n                        .collect(Collectors.toList());\n                    List<Rune> shadowRunes = constellationRunes.stream()\n                        .filter(r -> r.getResonance() == Resonance.SHADOW)\n                        .collect(Collectors.toList());\n                    \n                    int harmoniesFormed = 0;\n                    int minSize = Math.min(lightRunes.size(), shadowRunes.size());\n                    \n                    for (int i = 0; i < minSize; i++) {\n                        RuneHarmony harmony = new RuneHarmony(lightRunes.get(i), shadowRunes.get(i));\n                        crystallizeHarmony(harmony);\n                        harmoniesFormed++;\n                    }\n                    \n                    return harmoniesFormed;\n                } finally {\n                    latch.countDown();\n                }\n            });\n            futures.add(future);\n        }\n        \n        try {\n            latch.await();\n            int totalHarmonies = 0;\n            for (Future<Integer> future : futures) {\n                totalHarmonies += future.get();\n            }\n            return totalHarmonies;\n        } catch (InterruptedException | ExecutionException e) {\n            Thread.currentThread().interrupt();\n            return 0;\n        } finally {\n            executor.shutdown();\n            try {\n                if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                    executor.shutdownNow();\n                }\n            } catch (InterruptedException e) {\n                executor.shutdownNow();\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    private void crystallizeHarmony(RuneHarmony harmony) {\n        crystallizedHarmonies.add(harmony);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class GrimoireInscriber {\n    \n    public static void main(String[] args) {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK),\n            new Rune(Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(Constellation.LUNAR, Resonance.DARK),\n            new Rune(Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(Constellation.STELLAR, Resonance.DARK),\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        GrimoireInscriber inscriber = new GrimoireInscriber();\n        int harmonies = inscriber.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        \n        transmutedRunes.sort(new RuneComparator());\n        \n        Map<Constellation, List<Rune>> runesByConstellation = new ConcurrentHashMap<>();\n        for (Rune rune : transmutedRunes) {\n            runesByConstellation.computeIfAbsent(rune.getConstellation(), k -> new CopyOnWriteArrayList<>()).add(rune);\n        }\n        \n        List<Future<List<Harmony>>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            Future<List<Harmony>> future = executor.submit(() -> {\n                List<Harmony> localHarmonies = new ArrayList<>();\n                List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                List<Rune> lightRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                List<Rune> darkRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int pairs = Math.min(lightRunes.size(), darkRunes.size());\n                for (int i = 0; i < pairs; i++) {\n                    localHarmonies.add(new Harmony(lightRunes.get(i), darkRunes.get(i)));\n                }\n                return localHarmonies;\n            });\n            futures.add(future);\n        }\n        \n        List<Harmony> allHarmonies = new ArrayList<>();\n        for (Future<List<Harmony>> future : futures) {\n            try {\n                allHarmonies.addAll(future.get());\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        Grimoire grimoire = new Grimoire();\n        grimoire.crystallize(allHarmonies);\n        \n        return allHarmonies.size();\n    }\n    \n    class RuneComparator implements Comparator<Rune> {\n        @Override\n        public int compare(Rune r1, Rune r2) {\n            int constellationCompare = r1.getConstellation().compareTo(r2.getConstellation());\n            if (constellationCompare != 0) {\n                return constellationCompare;\n            }\n            return r1.getResonance().compareTo(r2.getResonance());\n        }\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK\n}\n\nclass Rune {\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(Constellation constellation, Resonance resonance) {\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nclass Harmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public Harmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<Harmony> crystallizedHarmonies;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new ArrayList<>();\n    }\n    \n    public synchronized void crystallize(List<Harmony> harmonies) {\n        crystallizedHarmonies.addAll(harmonies);\n    }\n    \n    public synchronized List<Harmony> getCrystallizedHarmonies() {\n        return new ArrayList<>(crystallizedHarmonies);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.SOLAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.LUNAR, Resonance.DARK)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    LUNAR, SOLAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK;\n    \n    public boolean isOpposite(Resonance other) {\n        return this != other;\n    }\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n    \n    public boolean canHarmonizeWith(Rune other) {\n        return this.constellation == other.constellation && \n               this.resonance.isOpposite(other.resonance);\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies;\n    private final ExecutorService executor;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = Collections.synchronizedList(new ArrayList<>());\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) {\n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        Collections.sort(transmutedRunes, runeComparator);\n        \n        Map<Constellation, List<Rune>> runesByConstellation = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        CountDownLatch latch = new CountDownLatch(runesByConstellation.size());\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            executor.submit(() -> {\n                try {\n                    List<Rune> constellationRunes = entry.getValue();\n                    List<Rune> lightRunes = constellationRunes.stream()\n                        .filter(r -> r.getResonance() == Resonance.LIGHT)\n                        .collect(Collectors.toList());\n                    List<Rune> darkRunes = constellationRunes.stream()\n                        .filter(r -> r.getResonance() == Resonance.DARK)\n                        .collect(Collectors.toList());\n                    \n                    for (Rune lightRune : lightRunes) {\n                        for (Rune darkRune : darkRunes) {\n                            if (lightRune.canHarmonizeWith(darkRune)) {\n                                crystallizeHarmony(new RuneHarmony(lightRune, darkRune));\n                            }\n                        }\n                    }\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.MINUTES);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        return crystallizedHarmonies.size();\n    }\n    \n    private void crystallizeHarmony(RuneHarmony harmony) {\n        crystallizedHarmonies.add(harmony);\n    }\n}"
        ],
        "graded_list": [
            false,
            true,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class Animals {\nprivate final Ark ark;\n\npublic Animals() {\nthis.ark = new Ark();\n}\n\npublic int loadTheArk(Collection<Animal> candidates) {\nSortedSet<Animal> animals;\nint numPairs = 0;\nAnimal candidate = null;\n\nanimals = new TreeSet<>(new SpeciesGenderComparator());\nanimals.addAll(candidates);\nfor (Animal a : animals) {\nif (candidate == null || !candidate.isPotentialMate(a)) {\ncandidate = a;\n} else {\nark.load(new AnimalPair(candidate, a));\n++numPairs;\ncandidate = null;\n}\n}\nreturn numPairs;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nAnimals animalsApp = new Animals();\n\nCollection<Animal> group1 = createSampleAnimals(4);\nCollection<Animal> group2 = createSampleAnimals(4);\n\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nexecutor.submit(() -> {\nint pairs = animalsApp.loadTheArk(group1);\nSystem.out.println(Thread.currentThread().getName() + \" loaded \" + pairs + \" pairs.\");\n});\n\nexecutor.submit(() -> {\nint pairs = animalsApp.loadTheArk(group2);\nSystem.out.println(Thread.currentThread().getName() + \" loaded \" + pairs + \" pairs.\");\n});\n\nexecutor.shutdown();\n}\n\nprivate static Collection<Animal> createSampleAnimals(int count) {\nList<Animal> list = new ArrayList<>();\nRandom rand = new Random();\nSpecies[] speciesArray = Species.values();\nGender[] genders = Gender.values();\n\nfor (int i = 0; i < count; i++) {\nAnimal animal = new Animal();\nanimal.species = speciesArray[rand.nextInt(speciesArray.length)];\nanimal.gender = genders[rand.nextInt(genders.length)];\nlist.add(animal);\n}\n\nreturn list;\n}\n\nstatic class Animal {\nSpecies species;\nGender gender;\n\npublic boolean isPotentialMate(Animal other) {\nreturn species == other.species && gender != other.gender;\n}\n}\n\nenum Species {\nAARDVARK, BENGAL_TIGER, CARIBOU, DINGO\n}\n\nenum Gender {\nMALE, FEMALE\n}\n\nstatic class AnimalPair {\nprivate final Animal one, two;\n\npublic AnimalPair(Animal one, Animal two) {\nthis.one = one;\nthis.two = two;\n}\n}\n\nstatic class SpeciesGenderComparator implements Comparator<Animal> {\npublic int compare(Animal one, Animal two) {\nint speciesCompare = one.species.compareTo(two.species);\nreturn (speciesCompare != 0)\n? speciesCompare\n: one.gender.compareTo(two.gender);\n}\n}\n\nstatic class Ark {\nprivate final Set<AnimalPair> loadedAnimals = Collections.synchronizedSet(new HashSet<>());\n\npublic void load(AnimalPair pair) {\nloadedAnimals.add(pair);\nSystem.out.println(Thread.currentThread().getName() + \" loaded a pair: \" + pair.hashCode());\n}\n}\n}",
        "max_depth": "133",
        "jpf_details": [
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=772,released=0,maxLive=0,gcCycles=0\ninstructions:       7700\nmax memory:         981MB\nloaded code:        classes=136,methods=2668\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 58.55%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 62.51%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.05%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=61102,visited=107631,backtracked=168638,end=490\nsearch:             maxDepth=162,constraints=0\nchoice generators:  thread=61101 (signal=0,lock=1818,sharedRef=55952,threadApi=2,reschedule=2076), data=0\nheap:               new=348768,released=387871,maxLive=1485,gcCycles=162969\ninstructions:       20746024\nmax memory:         1018MB\nloaded code:        classes=224,methods=3583\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=770,released=0,maxLive=0,gcCycles=0\ninstructions:       7693\nmax memory:         981MB\nloaded code:        classes=137,methods=2639\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"",
            "no errors detected",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\""
        ],
        "codebleu_score": [
            53.24,
            52.65,
            53.79
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.SOLAR, Resonance.SHADOW),\n            new Rune(\"Gamma\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.LUNAR, Resonance.SHADOW),\n            new Rune(\"Epsilon\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.SOLAR, Resonance.SHADOW),\n            new Rune(\"Eta\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.STELLAR, Resonance.SHADOW)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, SHADOW\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies;\n    private final ExecutorService executor;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new CopyOnWriteArrayList<>();\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) {\n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        transmutedRunes.sort(runeComparator);\n        \n        Map<Constellation, List<Rune>> runesByConstellation = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        CountDownLatch latch = new CountDownLatch(runesByConstellation.size());\n        List<Future<Integer>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            Future<Integer> future = executor.submit(() -> {\n                try {\n                    List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                    List<Rune> lightRunes = constellationRunes.stream()\n                        .filter(r -> r.getResonance() == Resonance.LIGHT)\n                        .collect(Collectors.toList());\n                    List<Rune> shadowRunes = constellationRunes.stream()\n                        .filter(r -> r.getResonance() == Resonance.SHADOW)\n                        .collect(Collectors.toList());\n                    \n                    int harmoniesFormed = 0;\n                    int minSize = Math.min(lightRunes.size(), shadowRunes.size());\n                    \n                    for (int i = 0; i < minSize; i++) {\n                        RuneHarmony harmony = new RuneHarmony(lightRunes.get(i), shadowRunes.get(i));\n                        crystallizeHarmony(harmony);\n                        harmoniesFormed++;\n                    }\n                    \n                    return harmoniesFormed;\n                } finally {\n                    latch.countDown();\n                }\n            });\n            futures.add(future);\n        }\n        \n        try {\n            latch.await();\n            int totalHarmonies = 0;\n            for (Future<Integer> future : futures) {\n                totalHarmonies += future.get();\n            }\n            return totalHarmonies;\n        } catch (InterruptedException | ExecutionException e) {\n            Thread.currentThread().interrupt();\n            return 0;\n        } finally {\n            executor.shutdown();\n            try {\n                if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                    executor.shutdownNow();\n                }\n            } catch (InterruptedException e) {\n                executor.shutdownNow();\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    private void crystallizeHarmony(RuneHarmony harmony) {\n        crystallizedHarmonies.add(harmony);\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class GrimoireInscriber {\n    \n    public static void main(String[] args) {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK),\n            new Rune(Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(Constellation.LUNAR, Resonance.DARK),\n            new Rune(Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(Constellation.STELLAR, Resonance.DARK),\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        GrimoireInscriber inscriber = new GrimoireInscriber();\n        int harmonies = inscriber.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        \n        transmutedRunes.sort(new RuneComparator());\n        \n        Map<Constellation, List<Rune>> runesByConstellation = new ConcurrentHashMap<>();\n        for (Rune rune : transmutedRunes) {\n            runesByConstellation.computeIfAbsent(rune.getConstellation(), k -> new CopyOnWriteArrayList<>()).add(rune);\n        }\n        \n        List<Future<List<Harmony>>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            Future<List<Harmony>> future = executor.submit(() -> {\n                List<Harmony> localHarmonies = new ArrayList<>();\n                List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                List<Rune> lightRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                List<Rune> darkRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int pairs = Math.min(lightRunes.size(), darkRunes.size());\n                for (int i = 0; i < pairs; i++) {\n                    localHarmonies.add(new Harmony(lightRunes.get(i), darkRunes.get(i)));\n                }\n                return localHarmonies;\n            });\n            futures.add(future);\n        }\n        \n        List<Harmony> allHarmonies = new ArrayList<>();\n        for (Future<List<Harmony>> future : futures) {\n            try {\n                allHarmonies.addAll(future.get());\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        Grimoire grimoire = new Grimoire();\n        grimoire.crystallize(allHarmonies);\n        \n        return allHarmonies.size();\n    }\n    \n    class RuneComparator implements Comparator<Rune> {\n        @Override\n        public int compare(Rune r1, Rune r2) {\n            int constellationCompare = r1.getConstellation().compareTo(r2.getConstellation());\n            if (constellationCompare != 0) {\n                return constellationCompare;\n            }\n            return r1.getResonance().compareTo(r2.getResonance());\n        }\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK\n}\n\nclass Rune {\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(Constellation constellation, Resonance resonance) {\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nclass Harmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public Harmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<Harmony> crystallizedHarmonies;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new ArrayList<>();\n    }\n    \n    public synchronized void crystallize(List<Harmony> harmonies) {\n        crystallizedHarmonies.addAll(harmonies);\n    }\n    \n    public synchronized List<Harmony> getCrystallizedHarmonies() {\n        return new ArrayList<>(crystallizedHarmonies);\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.SOLAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.LUNAR, Resonance.DARK)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    LUNAR, SOLAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK;\n    \n    public boolean isOpposite(Resonance other) {\n        return this != other;\n    }\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n    \n    public boolean canHarmonizeWith(Rune other) {\n        return this.constellation == other.constellation && \n               this.resonance.isOpposite(other.resonance);\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies;\n    private final ExecutorService executor;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = Collections.synchronizedList(new ArrayList<>());\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) {\n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        Collections.sort(transmutedRunes, runeComparator);\n        \n        Map<Constellation, List<Rune>> runesByConstellation = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        CountDownLatch latch = new CountDownLatch(runesByConstellation.size());\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            executor.submit(() -> {\n                try {\n                    List<Rune> constellationRunes = entry.getValue();\n                    List<Rune> lightRunes = constellationRunes.stream()\n                        .filter(r -> r.getResonance() == Resonance.LIGHT)\n                        .collect(Collectors.toList());\n                    List<Rune> darkRunes = constellationRunes.stream()\n                        .filter(r -> r.getResonance() == Resonance.DARK)\n                        .collect(Collectors.toList());\n                    \n                    for (Rune lightRune : lightRunes) {\n                        for (Rune darkRune : darkRunes) {\n                            if (lightRune.canHarmonizeWith(darkRune)) {\n                                crystallizeHarmony(new RuneHarmony(lightRune, darkRune));\n                            }\n                        }\n                    }\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.MINUTES);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        return crystallizedHarmonies.size();\n    }\n    \n    private void crystallizeHarmony(RuneHarmony harmony) {\n        crystallizedHarmonies.add(harmony);\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Thread confinement of local primitive and reference variables. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java program that models the process of inscribing runes onto a grimoire in harmonies. The program should define classes and enums representing runes, their constellation and resonance, and a mechanism for harmonizing runes based on constellation and resonance compatibility. Each rune has a constellation and resonance, and only runes of the same constellation and opposite resonances can form a harmony.\nThe main logic is implemented in a method called channelTheGrimoire, which takes a collection of candidate runes as input and returns the number of valid harmonies formed. Inside this method, runes are transmuted using a custom comparator that sequences them first by constellation and then by resonance. This ensures that runes of the same constellation and opposite resonances are woven together for harmonizing.\nAdditionally, implement a class to represent the grimoire that can crystallize these rune harmonies, and a helper class to represent each harmony of runes. Ensure proper encapsulation and thread confinement of variables within the method, preventing any unintended side effects or data sharing between threads. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        int harmonies = channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n    \n    public static int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        transmutedRunes.sort(new RuneComparator());\n        \n        Map<Constellation, List<Rune>> runesByConstellation = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        List<Future<List<RuneHarmony>>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            futures.add(executor.submit(() -> {\n                List<RuneHarmony> harmonies = new ArrayList<>();\n                List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                \n                List<Rune> lightRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                    \n                List<Rune> darkRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int minSize = Math.min(lightRunes.size(), darkRunes.size());\n                for (int i = 0; i < minSize; i++) {\n                    harmonies.add(new RuneHarmony(lightRunes.get(i), darkRunes.get(i)));\n                }\n                \n                return harmonies;\n            }));\n        }\n        \n        List<RuneHarmony> allHarmonies = new ArrayList<>();\n        for (Future<List<RuneHarmony>> future : futures) {\n            allHarmonies.addAll(future.get());\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        Grimoire grimoire = new Grimoire();\n        grimoire.crystallize(allHarmonies);\n        \n        return allHarmonies.size();\n    }\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nenum Constellation {\n    STELLAR, LUNAR, SOLAR\n}\n\nenum Resonance {\n    LIGHT, DARK\n}\n\nclass RuneComparator implements Comparator<Rune> {\n    public int compare(Rune r1, Rune r2) {\n        int constellationCompare = r1.getConstellation().compareTo(r2.getConstellation());\n        if (constellationCompare != 0) {\n            return constellationCompare;\n        }\n        return r1.getResonance().compareTo(r2.getResonance());\n    }\n}\n\nclass RuneHarmony {\n    private final Rune lightRune;\n    private final Rune darkRune;\n    \n    public RuneHarmony(Rune lightRune, Rune darkRune) {\n        this.lightRune = lightRune;\n        this.darkRune = darkRune;\n    }\n    \n    public Rune getLightRune() {\n        return lightRune;\n    }\n    \n    public Rune getDarkRune() {\n        return darkRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new ArrayList<>();\n    }\n    \n    public synchronized void crystallize(List<RuneHarmony> harmonies) {\n        crystallizedHarmonies.addAll(harmonies);\n    }\n    \n    public synchronized List<RuneHarmony> getCrystallizedHarmonies() {\n        return new ArrayList<>(crystallizedHarmonies);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.SOLAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.LUNAR, Resonance.DARK)\n        );\n        \n        RuneGrimoire grimoire = new RuneGrimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Number of harmonies formed: \" + harmonies);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        Collections.sort(transmutedRunes, new RuneComparator());\n        \n        Map<Constellation, List<Rune>> runesByConstellation = new ConcurrentHashMap<>();\n        for (Rune rune : transmutedRunes) {\n            runesByConstellation.computeIfAbsent(rune.getConstellation(), k -> new CopyOnWriteArrayList<>()).add(rune);\n        }\n        \n        Future<Integer> task1 = executor.submit(() -> {\n            int count = 0;\n            for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n                if (entry.getKey() == Constellation.LUNAR || entry.getKey() == Constellation.SOLAR) {\n                    count += processConstellation(entry.getValue());\n                }\n            }\n            return count;\n        });\n        \n        Future<Integer> task2 = executor.submit(() -> {\n            int count = 0;\n            for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n                if (entry.getKey() == Constellation.STELLAR || entry.getKey() == Constellation.VOID) {\n                    count += processConstellation(entry.getValue());\n                }\n            }\n            return count;\n        });\n        \n        int totalHarmonies = task1.get() + task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        return totalHarmonies;\n    }\n    \n    private int processConstellation(List<Rune> runes) {\n        List<Rune> lightRunes = new ArrayList<>();\n        List<Rune> darkRunes = new ArrayList<>();\n        \n        for (Rune rune : runes) {\n            if (rune.getResonance() == Resonance.LIGHT) {\n                lightRunes.add(rune);\n            } else {\n                darkRunes.add(rune);\n            }\n        }\n        \n        int harmonies = 0;\n        int minSize = Math.min(lightRunes.size(), darkRunes.size());\n        \n        for (int i = 0; i < minSize; i++) {\n            Harmony harmony = new Harmony(lightRunes.get(i), darkRunes.get(i));\n            if (harmony.isValid()) {\n                harmonies++;\n            }\n        }\n        \n        return harmonies;\n    }\n}\n\nenum Constellation {\n    LUNAR, SOLAR, STELLAR, VOID\n}\n\nenum Resonance {\n    LIGHT, DARK\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nclass RuneComparator implements Comparator<Rune> {\n    public int compare(Rune r1, Rune r2) {\n        int constellationCompare = r1.getConstellation().compareTo(r2.getConstellation());\n        if (constellationCompare != 0) {\n            return constellationCompare;\n        }\n        return r1.getResonance().compareTo(r2.getResonance());\n    }\n}\n\nclass Harmony {\n    private final Rune rune1;\n    private final Rune rune2;\n    \n    public Harmony(Rune rune1, Rune rune2) {\n        this.rune1 = rune1;\n        this.rune2 = rune2;\n    }\n    \n    public boolean isValid() {\n        return rune1.getConstellation() == rune2.getConstellation() &&\n               rune1.getResonance() != rune2.getResonance();\n    }\n    \n    public Rune getRune1() {\n        return rune1;\n    }\n    \n    public Rune getRune2() {\n        return rune2;\n    }\n}\n\nclass Grimoire {\n    private final List<Harmony> crystallizedHarmonies;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new CopyOnWriteArrayList<>();\n    }\n    \n    public void crystallize(Harmony harmony) {\n        if (harmony.isValid()) {\n            crystallizedHarmonies.add(harmony);\n        }\n    }\n    \n    public List<Harmony> getCrystallizedHarmonies() {\n        return new ArrayList<>(crystallizedHarmonies);\n    }\n    \n    public int getHarmonyCount() {\n        return crystallizedHarmonies.size();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class GrimoireInscription {\n    \n    public static void main(String[] args) throws Exception {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK),\n            new Rune(Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(Constellation.LUNAR, Resonance.DARK),\n            new Rune(Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(Constellation.STELLAR, Resonance.DARK),\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK;\n    \n    public Resonance opposite() {\n        return this == LIGHT ? DARK : LIGHT;\n    }\n}\n\nclass Rune {\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(Constellation constellation, Resonance resonance) {\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n    \n    public boolean canHarmonizeWith(Rune other) {\n        return this.constellation == other.constellation && \n               this.resonance == other.resonance.opposite();\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies;\n    private final ExecutorService executor;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new CopyOnWriteArrayList<>();\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws Exception {\n        List<Rune> runeList = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        Collections.sort(runeList, runeComparator);\n        \n        Map<Constellation, List<Rune>> runesByConstellation = runeList.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        List<Future<Integer>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            futures.add(executor.submit(() -> {\n                List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                int localHarmonies = 0;\n                \n                List<Rune> lightRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                List<Rune> darkRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int minSize = Math.min(lightRunes.size(), darkRunes.size());\n                \n                for (int i = 0; i < minSize; i++) {\n                    RuneHarmony harmony = new RuneHarmony(lightRunes.get(i), darkRunes.get(i));\n                    crystallizeHarmony(harmony);\n                    localHarmonies++;\n                }\n                \n                return localHarmonies;\n            }));\n        }\n        \n        int totalHarmonies = 0;\n        for (Future<Integer> future : futures) {\n            totalHarmonies += future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        return totalHarmonies;\n    }\n    \n    private void crystallizeHarmony(RuneHarmony harmony) {\n        crystallizedHarmonies.add(harmony);\n    }\n}"
        ],
        "graded_list": [
            false,
            true,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class Animals {\nprivate final Ark ark;\n\npublic Animals() {\nthis.ark = new Ark();\n}\n\npublic int loadTheArk(Collection<Animal> candidates) {\nSortedSet<Animal> animals;\nint numPairs = 0;\nAnimal candidate = null;\n\nanimals = new TreeSet<>(new SpeciesGenderComparator());\nanimals.addAll(candidates);\nfor (Animal a : animals) {\nif (candidate == null || !candidate.isPotentialMate(a)) {\ncandidate = a;\n} else {\nark.load(new AnimalPair(candidate, a));\n++numPairs;\ncandidate = null;\n}\n}\nreturn numPairs;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nAnimals animalsApp = new Animals();\n\nCollection<Animal> group1 = createSampleAnimals(4);\nCollection<Animal> group2 = createSampleAnimals(4);\n\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nexecutor.submit(() -> {\nint pairs = animalsApp.loadTheArk(group1);\nSystem.out.println(Thread.currentThread().getName() + \" loaded \" + pairs + \" pairs.\");\n});\n\nexecutor.submit(() -> {\nint pairs = animalsApp.loadTheArk(group2);\nSystem.out.println(Thread.currentThread().getName() + \" loaded \" + pairs + \" pairs.\");\n});\n\nexecutor.shutdown();\n}\n\nprivate static Collection<Animal> createSampleAnimals(int count) {\nList<Animal> list = new ArrayList<>();\nRandom rand = new Random();\nSpecies[] speciesArray = Species.values();\nGender[] genders = Gender.values();\n\nfor (int i = 0; i < count; i++) {\nAnimal animal = new Animal();\nanimal.species = speciesArray[rand.nextInt(speciesArray.length)];\nanimal.gender = genders[rand.nextInt(genders.length)];\nlist.add(animal);\n}\n\nreturn list;\n}\n\nstatic class Animal {\nSpecies species;\nGender gender;\n\npublic boolean isPotentialMate(Animal other) {\nreturn species == other.species && gender != other.gender;\n}\n}\n\nenum Species {\nAARDVARK, BENGAL_TIGER, CARIBOU, DINGO\n}\n\nenum Gender {\nMALE, FEMALE\n}\n\nstatic class AnimalPair {\nprivate final Animal one, two;\n\npublic AnimalPair(Animal one, Animal two) {\nthis.one = one;\nthis.two = two;\n}\n}\n\nstatic class SpeciesGenderComparator implements Comparator<Animal> {\npublic int compare(Animal one, Animal two) {\nint speciesCompare = one.species.compareTo(two.species);\nreturn (speciesCompare != 0)\n? speciesCompare\n: one.gender.compareTo(two.gender);\n}\n}\n\nstatic class Ark {\nprivate final Set<AnimalPair> loadedAnimals = Collections.synchronizedSet(new HashSet<>());\n\npublic void load(AnimalPair pair) {\nloadedAnimals.add(pair);\nSystem.out.println(Thread.currentThread().getName() + \" loaded a pair: \" + pair.hashCode());\n}\n}\n}",
        "max_depth": "133",
        "jpf_details": [
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.NoSuchMethodError: java.util.stream.Coll...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=1311,released=0,maxLive=0,gcCycles=0\ninstructions:       16634\nmax memory:         981MB\nloaded code:        classes=188,methods=3312\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 41.60%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 19.12%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 38.50%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=92083,visited=61743,backtracked=152507,end=27749\nsearch:             maxDepth=1330,constraints=8393\nchoice generators:  thread=86665 (signal=0,lock=4,sharedRef=42263,threadApi=2,reschedule=37323), data=0\nheap:               new=605237,released=2464886,maxLive=1202,gcCycles=153808\ninstructions:       54600597\nmax memory:         1012MB\nloaded code:        classes=171,methods=3013\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=756,released=0,maxLive=0,gcCycles=0\ninstructions:       7668\nmax memory:         981MB\nloaded code:        classes=136,methods=2669\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.NoSuchMethodError: java.util.stream.Coll...\"",
            "no errors detected",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\""
        ],
        "codebleu_score": [
            54.84,
            53.61,
            52.52
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        int harmonies = channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n    \n    public static int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        transmutedRunes.sort(new RuneComparator());\n        \n        Map<Constellation, List<Rune>> runesByConstellation = transmutedRunes.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        List<Future<List<RuneHarmony>>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            futures.add(executor.submit(() -> {\n                List<RuneHarmony> harmonies = new ArrayList<>();\n                List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                \n                List<Rune> lightRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                    \n                List<Rune> darkRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int minSize = Math.min(lightRunes.size(), darkRunes.size());\n                for (int i = 0; i < minSize; i++) {\n                    harmonies.add(new RuneHarmony(lightRunes.get(i), darkRunes.get(i)));\n                }\n                \n                return harmonies;\n            }));\n        }\n        \n        List<RuneHarmony> allHarmonies = new ArrayList<>();\n        for (Future<List<RuneHarmony>> future : futures) {\n            allHarmonies.addAll(future.get());\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        Grimoire grimoire = new Grimoire();\n        grimoire.crystallize(allHarmonies);\n        \n        return allHarmonies.size();\n    }\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nenum Constellation {\n    STELLAR, LUNAR, SOLAR\n}\n\nenum Resonance {\n    LIGHT, DARK\n}\n\nclass RuneComparator implements Comparator<Rune> {\n    public int compare(Rune r1, Rune r2) {\n        int constellationCompare = r1.getConstellation().compareTo(r2.getConstellation());\n        if (constellationCompare != 0) {\n            return constellationCompare;\n        }\n        return r1.getResonance().compareTo(r2.getResonance());\n    }\n}\n\nclass RuneHarmony {\n    private final Rune lightRune;\n    private final Rune darkRune;\n    \n    public RuneHarmony(Rune lightRune, Rune darkRune) {\n        this.lightRune = lightRune;\n        this.darkRune = darkRune;\n    }\n    \n    public Rune getLightRune() {\n        return lightRune;\n    }\n    \n    public Rune getDarkRune() {\n        return darkRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new ArrayList<>();\n    }\n    \n    public synchronized void crystallize(List<RuneHarmony> harmonies) {\n        crystallizedHarmonies.addAll(harmonies);\n    }\n    \n    public synchronized List<RuneHarmony> getCrystallizedHarmonies() {\n        return new ArrayList<>(crystallizedHarmonies);\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class RuneGrimoire {\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(\"Alpha\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Beta\", Constellation.LUNAR, Resonance.DARK),\n            new Rune(\"Gamma\", Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(\"Delta\", Constellation.SOLAR, Resonance.DARK),\n            new Rune(\"Epsilon\", Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(\"Zeta\", Constellation.STELLAR, Resonance.DARK),\n            new Rune(\"Eta\", Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(\"Theta\", Constellation.LUNAR, Resonance.DARK)\n        );\n        \n        RuneGrimoire grimoire = new RuneGrimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Number of harmonies formed: \" + harmonies);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        List<Rune> transmutedRunes = new ArrayList<>(candidateRunes);\n        Collections.sort(transmutedRunes, new RuneComparator());\n        \n        Map<Constellation, List<Rune>> runesByConstellation = new ConcurrentHashMap<>();\n        for (Rune rune : transmutedRunes) {\n            runesByConstellation.computeIfAbsent(rune.getConstellation(), k -> new CopyOnWriteArrayList<>()).add(rune);\n        }\n        \n        Future<Integer> task1 = executor.submit(() -> {\n            int count = 0;\n            for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n                if (entry.getKey() == Constellation.LUNAR || entry.getKey() == Constellation.SOLAR) {\n                    count += processConstellation(entry.getValue());\n                }\n            }\n            return count;\n        });\n        \n        Future<Integer> task2 = executor.submit(() -> {\n            int count = 0;\n            for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n                if (entry.getKey() == Constellation.STELLAR || entry.getKey() == Constellation.VOID) {\n                    count += processConstellation(entry.getValue());\n                }\n            }\n            return count;\n        });\n        \n        int totalHarmonies = task1.get() + task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        return totalHarmonies;\n    }\n    \n    private int processConstellation(List<Rune> runes) {\n        List<Rune> lightRunes = new ArrayList<>();\n        List<Rune> darkRunes = new ArrayList<>();\n        \n        for (Rune rune : runes) {\n            if (rune.getResonance() == Resonance.LIGHT) {\n                lightRunes.add(rune);\n            } else {\n                darkRunes.add(rune);\n            }\n        }\n        \n        int harmonies = 0;\n        int minSize = Math.min(lightRunes.size(), darkRunes.size());\n        \n        for (int i = 0; i < minSize; i++) {\n            Harmony harmony = new Harmony(lightRunes.get(i), darkRunes.get(i));\n            if (harmony.isValid()) {\n                harmonies++;\n            }\n        }\n        \n        return harmonies;\n    }\n}\n\nenum Constellation {\n    LUNAR, SOLAR, STELLAR, VOID\n}\n\nenum Resonance {\n    LIGHT, DARK\n}\n\nclass Rune {\n    private final String name;\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(String name, Constellation constellation, Resonance resonance) {\n        this.name = name;\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n}\n\nclass RuneComparator implements Comparator<Rune> {\n    public int compare(Rune r1, Rune r2) {\n        int constellationCompare = r1.getConstellation().compareTo(r2.getConstellation());\n        if (constellationCompare != 0) {\n            return constellationCompare;\n        }\n        return r1.getResonance().compareTo(r2.getResonance());\n    }\n}\n\nclass Harmony {\n    private final Rune rune1;\n    private final Rune rune2;\n    \n    public Harmony(Rune rune1, Rune rune2) {\n        this.rune1 = rune1;\n        this.rune2 = rune2;\n    }\n    \n    public boolean isValid() {\n        return rune1.getConstellation() == rune2.getConstellation() &&\n               rune1.getResonance() != rune2.getResonance();\n    }\n    \n    public Rune getRune1() {\n        return rune1;\n    }\n    \n    public Rune getRune2() {\n        return rune2;\n    }\n}\n\nclass Grimoire {\n    private final List<Harmony> crystallizedHarmonies;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new CopyOnWriteArrayList<>();\n    }\n    \n    public void crystallize(Harmony harmony) {\n        if (harmony.isValid()) {\n            crystallizedHarmonies.add(harmony);\n        }\n    }\n    \n    public List<Harmony> getCrystallizedHarmonies() {\n        return new ArrayList<>(crystallizedHarmonies);\n    }\n    \n    public int getHarmonyCount() {\n        return crystallizedHarmonies.size();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class GrimoireInscription {\n    \n    public static void main(String[] args) throws Exception {\n        List<Rune> candidateRunes = Arrays.asList(\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK),\n            new Rune(Constellation.LUNAR, Resonance.LIGHT),\n            new Rune(Constellation.LUNAR, Resonance.DARK),\n            new Rune(Constellation.STELLAR, Resonance.LIGHT),\n            new Rune(Constellation.STELLAR, Resonance.DARK),\n            new Rune(Constellation.SOLAR, Resonance.LIGHT),\n            new Rune(Constellation.SOLAR, Resonance.DARK)\n        );\n        \n        Grimoire grimoire = new Grimoire();\n        int harmonies = grimoire.channelTheGrimoire(candidateRunes);\n        System.out.println(\"Total harmonies formed: \" + harmonies);\n    }\n}\n\nenum Constellation {\n    SOLAR, LUNAR, STELLAR\n}\n\nenum Resonance {\n    LIGHT, DARK;\n    \n    public Resonance opposite() {\n        return this == LIGHT ? DARK : LIGHT;\n    }\n}\n\nclass Rune {\n    private final Constellation constellation;\n    private final Resonance resonance;\n    \n    public Rune(Constellation constellation, Resonance resonance) {\n        this.constellation = constellation;\n        this.resonance = resonance;\n    }\n    \n    public Constellation getConstellation() {\n        return constellation;\n    }\n    \n    public Resonance getResonance() {\n        return resonance;\n    }\n    \n    public boolean canHarmonizeWith(Rune other) {\n        return this.constellation == other.constellation && \n               this.resonance == other.resonance.opposite();\n    }\n}\n\nclass RuneHarmony {\n    private final Rune firstRune;\n    private final Rune secondRune;\n    \n    public RuneHarmony(Rune firstRune, Rune secondRune) {\n        this.firstRune = firstRune;\n        this.secondRune = secondRune;\n    }\n    \n    public Rune getFirstRune() {\n        return firstRune;\n    }\n    \n    public Rune getSecondRune() {\n        return secondRune;\n    }\n}\n\nclass Grimoire {\n    private final List<RuneHarmony> crystallizedHarmonies;\n    private final ExecutorService executor;\n    \n    public Grimoire() {\n        this.crystallizedHarmonies = new CopyOnWriteArrayList<>();\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public int channelTheGrimoire(Collection<Rune> candidateRunes) throws Exception {\n        List<Rune> runeList = new ArrayList<>(candidateRunes);\n        \n        Comparator<Rune> runeComparator = Comparator\n            .comparing(Rune::getConstellation)\n            .thenComparing(Rune::getResonance);\n        \n        Collections.sort(runeList, runeComparator);\n        \n        Map<Constellation, List<Rune>> runesByConstellation = runeList.stream()\n            .collect(Collectors.groupingBy(Rune::getConstellation));\n        \n        List<Future<Integer>> futures = new ArrayList<>();\n        \n        for (Map.Entry<Constellation, List<Rune>> entry : runesByConstellation.entrySet()) {\n            futures.add(executor.submit(() -> {\n                List<Rune> constellationRunes = new ArrayList<>(entry.getValue());\n                int localHarmonies = 0;\n                \n                List<Rune> lightRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.LIGHT)\n                    .collect(Collectors.toList());\n                List<Rune> darkRunes = constellationRunes.stream()\n                    .filter(r -> r.getResonance() == Resonance.DARK)\n                    .collect(Collectors.toList());\n                \n                int minSize = Math.min(lightRunes.size(), darkRunes.size());\n                \n                for (int i = 0; i < minSize; i++) {\n                    RuneHarmony harmony = new RuneHarmony(lightRunes.get(i), darkRunes.get(i));\n                    crystallizeHarmony(harmony);\n                    localHarmonies++;\n                }\n                \n                return localHarmonies;\n            }));\n        }\n        \n        int totalHarmonies = 0;\n        for (Future<Integer> future : futures) {\n            totalHarmonies += future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        return totalHarmonies;\n    }\n    \n    private void crystallizeHarmony(RuneHarmony harmony) {\n        crystallizedHarmonies.add(harmony);\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Immutable Point class used by DelegatingVehicleTracker. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create an immutable class named Whisker that represents a lattice in a floating sky-garden. The class should have two public final fields, spark and glimmer, both of type int, to store the lattice positions. The class should include a constructor that summons two integer parameters to imbue the spark and glimmer values. Ensure that no methods are added that could twist the essence of the object after manifestation. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class Whisker {\n    public final int spark;\n    public final int glimmer;\n    \n    public Whisker(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            Whisker w1 = new Whisker(10, 20);\n            System.out.println(\"Thread 1: spark=\" + w1.spark + \", glimmer=\" + w1.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w2 = new Whisker(30, 40);\n            System.out.println(\"Thread 2: spark=\" + w2.spark + \", glimmer=\" + w2.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w3 = new Whisker(50, 60);\n            System.out.println(\"Thread 3: spark=\" + w3.spark + \", glimmer=\" + w3.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w4 = new Whisker(70, 80);\n            System.out.println(\"Thread 4: spark=\" + w4.spark + \", glimmer=\" + w4.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w5 = new Whisker(90, 100);\n            System.out.println(\"Thread 5: spark=\" + w5.spark + \", glimmer=\" + w5.glimmer);\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class Whisker {\n    public final int spark;\n    public final int glimmer;\n    \n    public Whisker(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            Whisker w1 = new Whisker(10, 20);\n            System.out.println(\"Thread 1: spark=\" + w1.spark + \", glimmer=\" + w1.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w2 = new Whisker(30, 40);\n            System.out.println(\"Thread 2: spark=\" + w2.spark + \", glimmer=\" + w2.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w3 = new Whisker(50, 60);\n            System.out.println(\"Thread 3: spark=\" + w3.spark + \", glimmer=\" + w3.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w4 = new Whisker(70, 80);\n            System.out.println(\"Thread 4: spark=\" + w4.spark + \", glimmer=\" + w4.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w5 = new Whisker(90, 100);\n            System.out.println(\"Thread 5: spark=\" + w5.spark + \", glimmer=\" + w5.glimmer);\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class Whisker {\n    public final int spark;\n    public final int glimmer;\n    \n    public Whisker(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        AtomicInteger counter = new AtomicInteger(0);\n        \n        for (int i = 0; i < 5; i++) {\n            final int index = i;\n            executor.submit(() -> {\n                Whisker whisker = new Whisker(index * 10, index * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Whisker with spark: \" + whisker.spark + \n                    \", glimmer: \" + whisker.glimmer);\n                counter.incrementAndGet();\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            if (executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                System.out.println(\"All tasks completed. Total Whiskers created: \" + counter.get());\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "/**\n* Demonstrates creating Points in parallel threads without using ExecutorService.\n*/\nclass Point {\npublic final int x, y;\n\npublic Point(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\n@Override\npublic String toString() {\nreturn \"Point{\" +\n\"x=\" + x +\n\", y=\" + y +\n'}';\n}\n}\n\npublic class Main {\npublic static void main(String[] args) throws InterruptedException {\nThread[] threads = new Thread[5];\n\nfor (int i = 1; i <= 5; i++) {\nfinal int taskId = i;\nthreads[i - 1] = new Thread(() -> {\nPoint point = new Point(taskId * 10, taskId * 20);\nSystem.out.println(\"Task ID: \" + taskId + \", Generated Point: \" + point);\n});\n}\n\n// Start all threads\nfor (Thread t : threads) {\nt.start();\n}\n\n// Wait for all threads to finish\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"All tasks completed.\");\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.97%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 83.00%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=83197,visited=192394,backtracked=275391,end=4\nsearch:             maxDepth=200,constraints=89301\nchoice generators:  thread=46429 (signal=0,lock=7,sharedRef=45496,threadApi=5,reschedule=266), data=0\nheap:               new=178837,released=350680,maxLive=760,gcCycles=275591\ninstructions:       24389337\nmax memory:         1020MB\nloaded code:        classes=136,methods=2415\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.97%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.99%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=82771,visited=191342,backtracked=273913,end=4\nsearch:             maxDepth=200,constraints=88871\nchoice generators:  thread=46183 (signal=0,lock=7,sharedRef=45249,threadApi=5,reschedule=268), data=0\nheap:               new=176832,released=348056,maxLive=760,gcCycles=274113\ninstructions:       24268016\nmax memory:         1020MB\nloaded code:        classes=136,methods=2415\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.53%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.55%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.55%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.56%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.56%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=105491,visited=152813,backtracked=258104,end=5\nsearch:             maxDepth=200,constraints=116309\nchoice generators:  thread=44024 (signal=0,lock=7,sharedRef=40357,threadApi=5,reschedule=415), data=0\nheap:               new=79960,released=207188,maxLive=749,gcCycles=258304\ninstructions:       20821202\nmax memory:         1019MB\nloaded code:        classes=136,methods=2407\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            53.84,
            53.84,
            56.16
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class Whisker {\n    public final int spark;\n    public final int glimmer;\n    \n    public Whisker(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            Whisker w1 = new Whisker(10, 20);\n            System.out.println(\"Thread 1: spark=\" + w1.spark + \", glimmer=\" + w1.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w2 = new Whisker(30, 40);\n            System.out.println(\"Thread 2: spark=\" + w2.spark + \", glimmer=\" + w2.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w3 = new Whisker(50, 60);\n            System.out.println(\"Thread 3: spark=\" + w3.spark + \", glimmer=\" + w3.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w4 = new Whisker(70, 80);\n            System.out.println(\"Thread 4: spark=\" + w4.spark + \", glimmer=\" + w4.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w5 = new Whisker(90, 100);\n            System.out.println(\"Thread 5: spark=\" + w5.spark + \", glimmer=\" + w5.glimmer);\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class Whisker {\n    public final int spark;\n    public final int glimmer;\n    \n    public Whisker(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            Whisker w1 = new Whisker(10, 20);\n            System.out.println(\"Thread 1: spark=\" + w1.spark + \", glimmer=\" + w1.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w2 = new Whisker(30, 40);\n            System.out.println(\"Thread 2: spark=\" + w2.spark + \", glimmer=\" + w2.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w3 = new Whisker(50, 60);\n            System.out.println(\"Thread 3: spark=\" + w3.spark + \", glimmer=\" + w3.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w4 = new Whisker(70, 80);\n            System.out.println(\"Thread 4: spark=\" + w4.spark + \", glimmer=\" + w4.glimmer);\n        });\n        \n        executor.submit(() -> {\n            Whisker w5 = new Whisker(90, 100);\n            System.out.println(\"Thread 5: spark=\" + w5.spark + \", glimmer=\" + w5.glimmer);\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class Whisker {\n    public final int spark;\n    public final int glimmer;\n    \n    public Whisker(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        AtomicInteger counter = new AtomicInteger(0);\n        \n        for (int i = 0; i < 5; i++) {\n            final int index = i;\n            executor.submit(() -> {\n                Whisker whisker = new Whisker(index * 10, index * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Whisker with spark: \" + whisker.spark + \n                    \", glimmer: \" + whisker.glimmer);\n                counter.incrementAndGet();\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            if (executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                System.out.println(\"All tasks completed. Total Whiskers created: \" + counter.get());\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Immutable Point class used by DelegatingVehicleTracker. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create an immutable class named Fungloon that represents a constellation in a drifting bubble-realm. The class should have two public final fields, flint and drizzle, both of type int, to store the constellation coordinates. The class should include a constructor that chants two integer parameters to weave the flint and drizzle values. Ensure that no methods are added that could shimmer the essence of the object after emergence. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FungloonProgram {\n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadId = i;\n            executor.submit(() -> {\n                Fungloon fungloon = new Fungloon(threadId * 10, threadId * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Fungloon: flint=\" + fungloon.flint + \n                    \", drizzle=\" + fungloon.drizzle);\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nfinal class Fungloon {\n    public final int flint;\n    public final int drizzle;\n    \n    public Fungloon(int flint, int drizzle) {\n        this.flint = flint;\n        this.drizzle = drizzle;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FungloonProgram {\n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadNum = i;\n            executor.submit(() -> {\n                Fungloon fungloon = new Fungloon(threadNum * 10, threadNum * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Fungloon: flint=\" + fungloon.flint + \n                    \", drizzle=\" + fungloon.drizzle);\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nfinal class Fungloon {\n    public final int flint;\n    public final int drizzle;\n    \n    public Fungloon(int flint, int drizzle) {\n        this.flint = flint;\n        this.drizzle = drizzle;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FungloonProgram {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                Fungloon constellation = new Fungloon(taskId * 10, taskId * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Fungloon: flint=\" + constellation.flint + \n                    \", drizzle=\" + constellation.drizzle);\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nfinal class Fungloon {\n    public final int flint;\n    public final int drizzle;\n    \n    public Fungloon(int flint, int drizzle) {\n        this.flint = flint;\n        this.drizzle = drizzle;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "/**\n* Demonstrates creating Points in parallel threads without using ExecutorService.\n*/\nclass Point {\npublic final int x, y;\n\npublic Point(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\n@Override\npublic String toString() {\nreturn \"Point{\" +\n\"x=\" + x +\n\", y=\" + y +\n'}';\n}\n}\n\npublic class Main {\npublic static void main(String[] args) throws InterruptedException {\nThread[] threads = new Thread[5];\n\nfor (int i = 1; i <= 5; i++) {\nfinal int taskId = i;\nthreads[i - 1] = new Thread(() -> {\nPoint point = new Point(taskId * 10, taskId * 20);\nSystem.out.println(\"Task ID: \" + taskId + \", Generated Point: \" + point);\n});\n}\n\n// Start all threads\nfor (Thread t : threads) {\nt.start();\n}\n\n// Wait for all threads to finish\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"All tasks completed.\");\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.50%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.53%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.53%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.53%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.53%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=103143,visited=148460,backtracked=251403,end=5\nsearch:             maxDepth=200,constraints=114049\nchoice generators:  thread=42914 (signal=0,lock=7,sharedRef=39252,threadApi=5,reschedule=434), data=0\nheap:               new=118860,released=215491,maxLive=751,gcCycles=251603\ninstructions:       20410041\nmax memory:         1018MB\nloaded code:        classes=137,methods=2408\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.54%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.57%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.57%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.57%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.57%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=106890,visited=156481,backtracked=263173,end=5\nsearch:             maxDepth=200,constraints=118009\nchoice generators:  thread=44871 (signal=0,lock=7,sharedRef=41172,threadApi=5,reschedule=428), data=0\nheap:               new=124894,released=228289,maxLive=751,gcCycles=263371\ninstructions:       21368811\nmax memory:         1019MB\nloaded code:        classes=137,methods=2408\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.01%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.01%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 81.83%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 81.93%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 81.93%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=135665,visited=107709,backtracked=243174,end=5\nsearch:             maxDepth=200,constraints=152048\nchoice generators:  thread=42103 (signal=0,lock=7,sharedRef=35055,threadApi=5,reschedule=436), data=0\nheap:               new=61596,released=101575,maxLive=751,gcCycles=243374\ninstructions:       16544431\nmax memory:         1017MB\nloaded code:        classes=137,methods=2408\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            53.16,
            53.16,
            53.64
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FungloonProgram {\n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadId = i;\n            executor.submit(() -> {\n                Fungloon fungloon = new Fungloon(threadId * 10, threadId * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Fungloon: flint=\" + fungloon.flint + \n                    \", drizzle=\" + fungloon.drizzle);\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nfinal class Fungloon {\n    public final int flint;\n    public final int drizzle;\n    \n    public Fungloon(int flint, int drizzle) {\n        this.flint = flint;\n        this.drizzle = drizzle;\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FungloonProgram {\n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadNum = i;\n            executor.submit(() -> {\n                Fungloon fungloon = new Fungloon(threadNum * 10, threadNum * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Fungloon: flint=\" + fungloon.flint + \n                    \", drizzle=\" + fungloon.drizzle);\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nfinal class Fungloon {\n    public final int flint;\n    public final int drizzle;\n    \n    public Fungloon(int flint, int drizzle) {\n        this.flint = flint;\n        this.drizzle = drizzle;\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FungloonProgram {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                Fungloon constellation = new Fungloon(taskId * 10, taskId * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Fungloon: flint=\" + constellation.flint + \n                    \", drizzle=\" + constellation.drizzle);\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nfinal class Fungloon {\n    public final int flint;\n    public final int drizzle;\n    \n    public Fungloon(int flint, int drizzle) {\n        this.flint = flint;\n        this.drizzle = drizzle;\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Immutable Point class used by DelegatingVehicleTracker. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create an immutable class named Crimble that represents a glyph in a swirling cloud-forest. The class should have two public final fields, twine and glint, both of type int, to store the glyph positions. The class should include a constructor that conjures two integer parameters to anchor the twine and glint values. Ensure that no methods are added that could tangle the essence of the object after crystallization. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic final class Crimble {\n    public final int twine;\n    public final int glint;\n    \n    public Crimble(int twine, int glint) {\n        this.twine = twine;\n        this.glint = glint;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            Crimble c1 = new Crimble(10, 20);\n            System.out.println(\"Thread 1: twine=\" + c1.twine + \", glint=\" + c1.glint);\n        });\n        \n        executor.submit(() -> {\n            Crimble c2 = new Crimble(30, 40);\n            System.out.println(\"Thread 2: twine=\" + c2.twine + \", glint=\" + c2.glint);\n        });\n        \n        executor.submit(() -> {\n            Crimble c3 = new Crimble(50, 60);\n            System.out.println(\"Thread 3: twine=\" + c3.twine + \", glint=\" + c3.glint);\n        });\n        \n        executor.submit(() -> {\n            Crimble c4 = new Crimble(70, 80);\n            System.out.println(\"Thread 4: twine=\" + c4.twine + \", glint=\" + c4.glint);\n        });\n        \n        executor.submit(() -> {\n            Crimble c5 = new Crimble(90, 100);\n            System.out.println(\"Thread 5: twine=\" + c5.twine + \", glint=\" + c5.glint);\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic final class Crimble {\n    public final int twine;\n    public final int glint;\n    \n    public Crimble(int twine, int glint) {\n        this.twine = twine;\n        this.glint = glint;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int index = i;\n            executor.submit(() -> {\n                Crimble crimble = new Crimble(index * 10, index * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Crimble with twine=\" + crimble.twine + \n                    \", glint=\" + crimble.glint);\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic final class Crimble {\n    public final int twine;\n    public final int glint;\n    \n    public Crimble(int twine, int glint) {\n        this.twine = twine;\n        this.glint = glint;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadNum = i;\n            executor.submit(() -> {\n                Crimble crimble = new Crimble(threadNum * 10, threadNum * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                                 \" created Crimble with twine=\" + crimble.twine + \n                                 \", glint=\" + crimble.glint);\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "/**\n* Demonstrates creating Points in parallel threads without using ExecutorService.\n*/\nclass Point {\npublic final int x, y;\n\npublic Point(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\n@Override\npublic String toString() {\nreturn \"Point{\" +\n\"x=\" + x +\n\", y=\" + y +\n'}';\n}\n}\n\npublic class Main {\npublic static void main(String[] args) throws InterruptedException {\nThread[] threads = new Thread[5];\n\nfor (int i = 1; i <= 5; i++) {\nfinal int taskId = i;\nthreads[i - 1] = new Thread(() -> {\nPoint point = new Point(taskId * 10, taskId * 20);\nSystem.out.println(\"Task ID: \" + taskId + \", Generated Point: \" + point);\n});\n}\n\n// Start all threads\nfor (Thread t : threads) {\nt.start();\n}\n\n// Wait for all threads to finish\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"All tasks completed.\");\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 83.01%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 83.01%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.97%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 83.00%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=83651,visited=193715,backtracked=277166,end=4\nsearch:             maxDepth=200,constraints=89778\nchoice generators:  thread=46725 (signal=0,lock=7,sharedRef=45791,threadApi=5,reschedule=268), data=0\nheap:               new=179693,released=352799,maxLive=760,gcCycles=277366\ninstructions:       24524631\nmax memory:         1020MB\nloaded code:        classes=136,methods=2415\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.52%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.55%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.55%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.55%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.55%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=104041,visited=151705,backtracked=255551,end=5\nsearch:             maxDepth=200,constraints=114941\nchoice generators:  thread=43594 (signal=0,lock=7,sharedRef=40000,threadApi=5,reschedule=404), data=0\nheap:               new=106246,released=221525,maxLive=748,gcCycles=255746\ninstructions:       20786265\nmax memory:         1019MB\nloaded code:        classes=136,methods=2407\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.98%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.98%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.97%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.96%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.96%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=84206,visited=194564,backtracked=278572,end=4\nsearch:             maxDepth=200,constraints=90393\nchoice generators:  thread=46998 (signal=0,lock=7,sharedRef=46004,threadApi=5,reschedule=313), data=0\nheap:               new=159057,released=332267,maxLive=748,gcCycles=278770\ninstructions:       24457576\nmax memory:         1020MB\nloaded code:        classes=136,methods=2407\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            53.84,
            56.16,
            56.16
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic final class Crimble {\n    public final int twine;\n    public final int glint;\n    \n    public Crimble(int twine, int glint) {\n        this.twine = twine;\n        this.glint = glint;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            Crimble c1 = new Crimble(10, 20);\n            System.out.println(\"Thread 1: twine=\" + c1.twine + \", glint=\" + c1.glint);\n        });\n        \n        executor.submit(() -> {\n            Crimble c2 = new Crimble(30, 40);\n            System.out.println(\"Thread 2: twine=\" + c2.twine + \", glint=\" + c2.glint);\n        });\n        \n        executor.submit(() -> {\n            Crimble c3 = new Crimble(50, 60);\n            System.out.println(\"Thread 3: twine=\" + c3.twine + \", glint=\" + c3.glint);\n        });\n        \n        executor.submit(() -> {\n            Crimble c4 = new Crimble(70, 80);\n            System.out.println(\"Thread 4: twine=\" + c4.twine + \", glint=\" + c4.glint);\n        });\n        \n        executor.submit(() -> {\n            Crimble c5 = new Crimble(90, 100);\n            System.out.println(\"Thread 5: twine=\" + c5.twine + \", glint=\" + c5.glint);\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic final class Crimble {\n    public final int twine;\n    public final int glint;\n    \n    public Crimble(int twine, int glint) {\n        this.twine = twine;\n        this.glint = glint;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int index = i;\n            executor.submit(() -> {\n                Crimble crimble = new Crimble(index * 10, index * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                    \" created Crimble with twine=\" + crimble.twine + \n                    \", glint=\" + crimble.glint);\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic final class Crimble {\n    public final int twine;\n    public final int glint;\n    \n    public Crimble(int twine, int glint) {\n        this.twine = twine;\n        this.glint = glint;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadNum = i;\n            executor.submit(() -> {\n                Crimble crimble = new Crimble(threadNum * 10, threadNum * 20);\n                System.out.println(\"Thread \" + Thread.currentThread().getName() + \n                                 \" created Crimble with twine=\" + crimble.twine + \n                                 \", glint=\" + crimble.glint);\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Delegating thread safety to a ConcurrentHashMap. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called MysticBeastTracker that orchestrates the perches of sky-beasts in a thread-safe dreamscape. The class should use a ConcurrentHashMap to store beast perches, where each beast is marked by a unique String sigil and its current perch is represented by a Glyph object. Provide the following functionality: \nA constructor that welcomes an initial Map of beast sigils to Glyphs and imbues the internal concurrent map with these values. \nA method getPerches() that reveals an unmodifiable view of the current beast perches to prevent external tinkering. \nA method getPerch(String sigil) that displays the current perch of the specified beast or null if the beast does not exist. \nA method setPerch(String sigil, int spark, int glimmer) that transmutes the perch of an existing beast with the given sigil to the new coordinates (spark, glimmer). If the beast does not exist, this method should evoke an appropriate exception such as IllegalArgumentException. \nAn alternative method getPerchesAsStatic() that captures a snapshot of the current perches as an unmodifiable Map to provide a consistent view of all perches at the moment of invocation. \nEnsure that all operations are thread-safe without requiring additional synchronization in the class. Use standard Java libraries for concurrency and collections. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Glyph {\n    private final int spark;\n    private final int glimmer;\n    \n    public Glyph(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public int getSpark() {\n        return spark;\n    }\n    \n    public int getGlimmer() {\n        return glimmer;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Glyph(\" + spark + \", \" + glimmer + \")\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Glyph glyph = (Glyph) obj;\n        return spark == glyph.spark && glimmer == glyph.glimmer;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(spark, glimmer);\n    }\n}\n\npublic class MysticBeastTracker {\n    private final ConcurrentHashMap<String, Glyph> beastPerches;\n    \n    public MysticBeastTracker(Map<String, Glyph> initialPerches) {\n        this.beastPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Glyph> getPerches() {\n        return Collections.unmodifiableMap(beastPerches);\n    }\n    \n    public Glyph getPerch(String sigil) {\n        return beastPerches.get(sigil);\n    }\n    \n    public void setPerch(String sigil, int spark, int glimmer) {\n        Glyph newGlyph = new Glyph(spark, glimmer);\n        Glyph oldGlyph = beastPerches.replace(sigil, newGlyph);\n        if (oldGlyph == null) {\n            throw new IllegalArgumentException(\"Beast with sigil '\" + sigil + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Glyph> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastPerches));\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Glyph> initialPerches = new HashMap<>();\n        initialPerches.put(\"Phoenix\", new Glyph(100, 200));\n        initialPerches.put(\"Dragon\", new Glyph(150, 250));\n        initialPerches.put(\"Griffin\", new Glyph(75, 125));\n        initialPerches.put(\"Pegasus\", new Glyph(90, 180));\n        initialPerches.put(\"Thunderbird\", new Glyph(110, 220));\n        \n        MysticBeastTracker tracker = new MysticBeastTracker(initialPerches);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        CountDownLatch latch = new CountDownLatch(5);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    tracker.setPerch(\"Phoenix\", 100 + i * 10, 200 + i * 10);\n                    Thread.sleep(50);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    tracker.setPerch(\"Dragon\", 150 - i * 5, 250 - i * 5);\n                    Thread.sleep(60);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 8; i++) {\n                    Glyph perch = tracker.getPerch(\"Griffin\");\n                    if (perch != null) {\n                        System.out.println(\"Griffin at: \" + perch);\n                    }\n                    Thread.sleep(70);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    Map<String, Glyph> snapshot = tracker.getPerchesAsStatic();\n                    System.out.println(\"Snapshot \" + i + \": \" + snapshot.size() + \" beasts\");\n                    Thread.sleep(100);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    tracker.setPerch(\"Pegasus\", 90 + i * 15, 180 + i * 15);\n                    tracker.setPerch(\"Thunderbird\", 110 - i * 8, 220 - i * 8);\n                    Thread.sleep(45);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"\\nFinal perches:\");\n        Map<String, Glyph> finalPerches = tracker.getPerches();\n        for (Map.Entry<String, Glyph> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Glyph {\n    private final int spark;\n    private final int glimmer;\n    \n    public Glyph(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public int getSpark() {\n        return spark;\n    }\n    \n    public int getGlimmer() {\n        return glimmer;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Glyph[spark=\" + spark + \", glimmer=\" + glimmer + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Glyph glyph = (Glyph) o;\n        return spark == glyph.spark && glimmer == glyph.glimmer;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(spark, glimmer);\n    }\n}\n\nclass MysticBeastTracker {\n    private final ConcurrentHashMap<String, Glyph> beastPerches;\n    \n    public MysticBeastTracker(Map<String, Glyph> initialPerches) {\n        this.beastPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Glyph> getPerches() {\n        return Collections.unmodifiableMap(beastPerches);\n    }\n    \n    public Glyph getPerch(String sigil) {\n        return beastPerches.get(sigil);\n    }\n    \n    public void setPerch(String sigil, int spark, int glimmer) {\n        Glyph newGlyph = new Glyph(spark, glimmer);\n        Glyph oldGlyph = beastPerches.replace(sigil, newGlyph);\n        if (oldGlyph == null) {\n            throw new IllegalArgumentException(\"Beast with sigil '\" + sigil + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Glyph> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastPerches));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Glyph> initialPerches = new HashMap<>();\n        initialPerches.put(\"Phoenix\", new Glyph(100, 200));\n        initialPerches.put(\"Dragon\", new Glyph(150, 250));\n        initialPerches.put(\"Griffin\", new Glyph(75, 125));\n        initialPerches.put(\"Pegasus\", new Glyph(90, 180));\n        initialPerches.put(\"Wyvern\", new Glyph(110, 220));\n        \n        MysticBeastTracker tracker = new MysticBeastTracker(initialPerches);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Phoenix\", 100 + i * 10, 200 + i * 10);\n                    Thread.sleep(50);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Dragon\", 150 + i * 5, 250 + i * 5);\n                    Thread.sleep(60);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                Glyph perch = tracker.getPerch(\"Phoenix\");\n                System.out.println(\"Phoenix perch: \" + perch);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Glyph> snapshot = tracker.getPerchesAsStatic();\n                System.out.println(\"Snapshot \" + i + \": \" + snapshot.size() + \" beasts\");\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Griffin\", 75 + i * 3, 125 + i * 3);\n                    tracker.setPerch(\"Pegasus\", 90 + i * 2, 180 + i * 2);\n                    Thread.sleep(70);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Final perches:\");\n        Map<String, Glyph> finalPerches = tracker.getPerches();\n        for (Map.Entry<String, Glyph> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Glyph {\n    private final int spark;\n    private final int glimmer;\n    \n    public Glyph(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public int getSpark() {\n        return spark;\n    }\n    \n    public int getGlimmer() {\n        return glimmer;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Glyph[spark=\" + spark + \", glimmer=\" + glimmer + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Glyph glyph = (Glyph) o;\n        return spark == glyph.spark && glimmer == glyph.glimmer;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(spark, glimmer);\n    }\n}\n\nclass MysticBeastTracker {\n    private final ConcurrentHashMap<String, Glyph> beastPerches;\n    \n    public MysticBeastTracker(Map<String, Glyph> initialPerches) {\n        this.beastPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Glyph> getPerches() {\n        return Collections.unmodifiableMap(beastPerches);\n    }\n    \n    public Glyph getPerch(String sigil) {\n        return beastPerches.get(sigil);\n    }\n    \n    public void setPerch(String sigil, int spark, int glimmer) {\n        Glyph newGlyph = new Glyph(spark, glimmer);\n        Glyph oldGlyph = beastPerches.replace(sigil, newGlyph);\n        if (oldGlyph == null) {\n            throw new IllegalArgumentException(\"Beast with sigil '\" + sigil + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Glyph> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastPerches));\n    }\n}\n\npublic class BeastTrackerApp {\n    public static void main(String[] args) {\n        Map<String, Glyph> initialPerches = new HashMap<>();\n        initialPerches.put(\"Phoenix\", new Glyph(100, 200));\n        initialPerches.put(\"Dragon\", new Glyph(300, 400));\n        initialPerches.put(\"Griffin\", new Glyph(500, 600));\n        initialPerches.put(\"Pegasus\", new Glyph(700, 800));\n        initialPerches.put(\"Roc\", new Glyph(900, 1000));\n        \n        MysticBeastTracker tracker = new MysticBeastTracker(initialPerches);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Phoenix\", 100 + i * 10, 200 + i * 10);\n                    System.out.println(\"Thread 1 updated Phoenix: \" + tracker.getPerch(\"Phoenix\"));\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Dragon\", 300 + i * 5, 400 + i * 5);\n                    System.out.println(\"Thread 2 updated Dragon: \" + tracker.getPerch(\"Dragon\"));\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    Map<String, Glyph> snapshot = tracker.getPerchesAsStatic();\n                    System.out.println(\"Thread 3 snapshot \" + i + \": \" + snapshot.size() + \" beasts\");\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                try {\n                    Glyph griffinPerch = tracker.getPerch(\"Griffin\");\n                    if (griffinPerch != null) {\n                        tracker.setPerch(\"Griffin\", griffinPerch.getSpark() + 1, griffinPerch.getGlimmer() + 1);\n                        System.out.println(\"Thread 4 updated Griffin: \" + tracker.getPerch(\"Griffin\"));\n                    }\n                    Thread.sleep(70);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 6; i++) {\n                try {\n                    Map<String, Glyph> perches = tracker.getPerches();\n                    System.out.println(\"Thread 5 viewing perches, count: \" + perches.size());\n                    Thread.sleep(80);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(2, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"\\nFinal beast perches:\");\n        tracker.getPerches().forEach((sigil, glyph) -> \n            System.out.println(sigil + \": \" + glyph));\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.awt.Point;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.concurrent.ConcurrentMap;\nimport java.util.Collections;\n\n/**\n* DelegatingVehicleTracker\n* Tracks vehicle locations using a thread-safe ConcurrentHashMap.\n* Modified to use explicit Threads for JPF compatibility.\n*/\npublic class DelegatingVehicleTracker {\nprivate final ConcurrentMap<String, Point> locations;\nprivate final Map<String, Point> unmodifiableMap;\n\npublic DelegatingVehicleTracker(Map<String, Point> points) {\nlocations = new ConcurrentHashMap<>(points);\nunmodifiableMap = Collections.unmodifiableMap(locations);\n}\n\npublic Map<String, Point> getLocations() {\nreturn unmodifiableMap;\n}\n\npublic Point getLocation(String id) {\nreturn locations.get(id);\n}\n\npublic void setLocation(String id, int x, int y) {\nif (locations.replace(id, new Point(x, y)) == null)\nthrow new IllegalArgumentException(\"Invalid vehicle ID: \" + id);\n}\n\npublic Map<String, Point> getLocationsAsStatic() {\nreturn Collections.unmodifiableMap(new HashMap<>(locations));\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, Point> initialLocations = new HashMap<>();\ninitialLocations.put(\"V1\", new Point(0, 0));\ninitialLocations.put(\"V2\", new Point(10, 10));\ninitialLocations.put(\"V3\", new Point(20, 20));\n\nDelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n\n// Reduce thread count and iterations to shorten JPF testing time\nThread[] threads = new Thread[2]; // fewer threads\n\nfor (int i = 0; i < 2; i++) {\nfinal int threadId = i;\nthreads[i] = new Thread(() -> {\nRandom rand = new Random();\nfor (int j = 0; j < 3; j++) { // fewer iterations\nString vehicleId = \"V\" + ((threadId % 3) + 1);\nint newX = rand.nextInt(21); // 0 to 20\nint newY = rand.nextInt(21); // 0 to 20\nSystem.out.println(\"Thread-\" + threadId + \": Setting \" + vehicleId + \" to (\" + newX + \", \" + newY + \")\");\ntracker.setLocation(vehicleId, newX, newY);\ntry {\nThread.sleep(20); // shorter sleep to speed up execution\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\nfor (Map.Entry<String, Point> entry : tracker.getLocations().entrySet()) {\nSystem.out.println(entry.getKey() + \" => \" + entry.getValue());\n}\n}\n}",
        "max_depth": "81",
        "jpf_details": [
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.20%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 40.49%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 41.03%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 41.36%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 32.94%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 68.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=45572,visited=89670,backtracked=134467,end=320\nsearch:             maxDepth=810,constraints=11275\nchoice generators:  thread=37058 (signal=0,lock=27,sharedRef=25394,threadApi=38,reschedule=10124), data=0\nheap:               new=763728,released=774599,maxLive=915,gcCycles=135074\ninstructions:       96555000\nmax memory:         1014MB\nloaded code:        classes=163,methods=2741\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.72%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.72%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.72%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.72%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.72%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=76782,visited=89161,backtracked=165134,end=0\nsearch:             maxDepth=810,constraints=86557\nchoice generators:  thread=28665 (signal=0,lock=170,sharedRef=24424,threadApi=259,reschedule=235), data=0\nheap:               new=1579606,released=1085459,maxLive=899,gcCycles=165804\ninstructions:       41157559\nmax memory:         1017MB\nloaded code:        classes=158,methods=2699\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.06%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.99%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 83.00%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 83.00%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=69497,visited=135040,backtracked=203730,end=0\nsearch:             maxDepth=810,constraints=75396\nchoice generators:  thread=34768 (signal=0,lock=39,sharedRef=32762,threadApi=151,reschedule=20), data=0\nheap:               new=167824,released=66086,maxLive=896,gcCycles=203961\ninstructions:       43643653\nmax memory:         1018MB\nloaded code:        classes=155,methods=2706\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            63.51,
            60.03,
            61.86
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Glyph {\n    private final int spark;\n    private final int glimmer;\n    \n    public Glyph(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public int getSpark() {\n        return spark;\n    }\n    \n    public int getGlimmer() {\n        return glimmer;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Glyph(\" + spark + \", \" + glimmer + \")\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Glyph glyph = (Glyph) obj;\n        return spark == glyph.spark && glimmer == glyph.glimmer;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(spark, glimmer);\n    }\n}\n\npublic class MysticBeastTracker {\n    private final ConcurrentHashMap<String, Glyph> beastPerches;\n    \n    public MysticBeastTracker(Map<String, Glyph> initialPerches) {\n        this.beastPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Glyph> getPerches() {\n        return Collections.unmodifiableMap(beastPerches);\n    }\n    \n    public Glyph getPerch(String sigil) {\n        return beastPerches.get(sigil);\n    }\n    \n    public void setPerch(String sigil, int spark, int glimmer) {\n        Glyph newGlyph = new Glyph(spark, glimmer);\n        Glyph oldGlyph = beastPerches.replace(sigil, newGlyph);\n        if (oldGlyph == null) {\n            throw new IllegalArgumentException(\"Beast with sigil '\" + sigil + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Glyph> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastPerches));\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Glyph> initialPerches = new HashMap<>();\n        initialPerches.put(\"Phoenix\", new Glyph(100, 200));\n        initialPerches.put(\"Dragon\", new Glyph(150, 250));\n        initialPerches.put(\"Griffin\", new Glyph(75, 125));\n        initialPerches.put(\"Pegasus\", new Glyph(90, 180));\n        initialPerches.put(\"Thunderbird\", new Glyph(110, 220));\n        \n        MysticBeastTracker tracker = new MysticBeastTracker(initialPerches);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        CountDownLatch latch = new CountDownLatch(5);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    tracker.setPerch(\"Phoenix\", 100 + i * 10, 200 + i * 10);\n                    Thread.sleep(50);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    tracker.setPerch(\"Dragon\", 150 - i * 5, 250 - i * 5);\n                    Thread.sleep(60);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 8; i++) {\n                    Glyph perch = tracker.getPerch(\"Griffin\");\n                    if (perch != null) {\n                        System.out.println(\"Griffin at: \" + perch);\n                    }\n                    Thread.sleep(70);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    Map<String, Glyph> snapshot = tracker.getPerchesAsStatic();\n                    System.out.println(\"Snapshot \" + i + \": \" + snapshot.size() + \" beasts\");\n                    Thread.sleep(100);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    tracker.setPerch(\"Pegasus\", 90 + i * 15, 180 + i * 15);\n                    tracker.setPerch(\"Thunderbird\", 110 - i * 8, 220 - i * 8);\n                    Thread.sleep(45);\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"\\nFinal perches:\");\n        Map<String, Glyph> finalPerches = tracker.getPerches();\n        for (Map.Entry<String, Glyph> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Glyph {\n    private final int spark;\n    private final int glimmer;\n    \n    public Glyph(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public int getSpark() {\n        return spark;\n    }\n    \n    public int getGlimmer() {\n        return glimmer;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Glyph[spark=\" + spark + \", glimmer=\" + glimmer + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Glyph glyph = (Glyph) o;\n        return spark == glyph.spark && glimmer == glyph.glimmer;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(spark, glimmer);\n    }\n}\n\nclass MysticBeastTracker {\n    private final ConcurrentHashMap<String, Glyph> beastPerches;\n    \n    public MysticBeastTracker(Map<String, Glyph> initialPerches) {\n        this.beastPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Glyph> getPerches() {\n        return Collections.unmodifiableMap(beastPerches);\n    }\n    \n    public Glyph getPerch(String sigil) {\n        return beastPerches.get(sigil);\n    }\n    \n    public void setPerch(String sigil, int spark, int glimmer) {\n        Glyph newGlyph = new Glyph(spark, glimmer);\n        Glyph oldGlyph = beastPerches.replace(sigil, newGlyph);\n        if (oldGlyph == null) {\n            throw new IllegalArgumentException(\"Beast with sigil '\" + sigil + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Glyph> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastPerches));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Glyph> initialPerches = new HashMap<>();\n        initialPerches.put(\"Phoenix\", new Glyph(100, 200));\n        initialPerches.put(\"Dragon\", new Glyph(150, 250));\n        initialPerches.put(\"Griffin\", new Glyph(75, 125));\n        initialPerches.put(\"Pegasus\", new Glyph(90, 180));\n        initialPerches.put(\"Wyvern\", new Glyph(110, 220));\n        \n        MysticBeastTracker tracker = new MysticBeastTracker(initialPerches);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Phoenix\", 100 + i * 10, 200 + i * 10);\n                    Thread.sleep(50);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Dragon\", 150 + i * 5, 250 + i * 5);\n                    Thread.sleep(60);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                Glyph perch = tracker.getPerch(\"Phoenix\");\n                System.out.println(\"Phoenix perch: \" + perch);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Glyph> snapshot = tracker.getPerchesAsStatic();\n                System.out.println(\"Snapshot \" + i + \": \" + snapshot.size() + \" beasts\");\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Griffin\", 75 + i * 3, 125 + i * 3);\n                    tracker.setPerch(\"Pegasus\", 90 + i * 2, 180 + i * 2);\n                    Thread.sleep(70);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Final perches:\");\n        Map<String, Glyph> finalPerches = tracker.getPerches();\n        for (Map.Entry<String, Glyph> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Glyph {\n    private final int spark;\n    private final int glimmer;\n    \n    public Glyph(int spark, int glimmer) {\n        this.spark = spark;\n        this.glimmer = glimmer;\n    }\n    \n    public int getSpark() {\n        return spark;\n    }\n    \n    public int getGlimmer() {\n        return glimmer;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Glyph[spark=\" + spark + \", glimmer=\" + glimmer + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Glyph glyph = (Glyph) o;\n        return spark == glyph.spark && glimmer == glyph.glimmer;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(spark, glimmer);\n    }\n}\n\nclass MysticBeastTracker {\n    private final ConcurrentHashMap<String, Glyph> beastPerches;\n    \n    public MysticBeastTracker(Map<String, Glyph> initialPerches) {\n        this.beastPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Glyph> getPerches() {\n        return Collections.unmodifiableMap(beastPerches);\n    }\n    \n    public Glyph getPerch(String sigil) {\n        return beastPerches.get(sigil);\n    }\n    \n    public void setPerch(String sigil, int spark, int glimmer) {\n        Glyph newGlyph = new Glyph(spark, glimmer);\n        Glyph oldGlyph = beastPerches.replace(sigil, newGlyph);\n        if (oldGlyph == null) {\n            throw new IllegalArgumentException(\"Beast with sigil '\" + sigil + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Glyph> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastPerches));\n    }\n}\n\npublic class BeastTrackerApp {\n    public static void main(String[] args) {\n        Map<String, Glyph> initialPerches = new HashMap<>();\n        initialPerches.put(\"Phoenix\", new Glyph(100, 200));\n        initialPerches.put(\"Dragon\", new Glyph(300, 400));\n        initialPerches.put(\"Griffin\", new Glyph(500, 600));\n        initialPerches.put(\"Pegasus\", new Glyph(700, 800));\n        initialPerches.put(\"Roc\", new Glyph(900, 1000));\n        \n        MysticBeastTracker tracker = new MysticBeastTracker(initialPerches);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Phoenix\", 100 + i * 10, 200 + i * 10);\n                    System.out.println(\"Thread 1 updated Phoenix: \" + tracker.getPerch(\"Phoenix\"));\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"Dragon\", 300 + i * 5, 400 + i * 5);\n                    System.out.println(\"Thread 2 updated Dragon: \" + tracker.getPerch(\"Dragon\"));\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    Map<String, Glyph> snapshot = tracker.getPerchesAsStatic();\n                    System.out.println(\"Thread 3 snapshot \" + i + \": \" + snapshot.size() + \" beasts\");\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                try {\n                    Glyph griffinPerch = tracker.getPerch(\"Griffin\");\n                    if (griffinPerch != null) {\n                        tracker.setPerch(\"Griffin\", griffinPerch.getSpark() + 1, griffinPerch.getGlimmer() + 1);\n                        System.out.println(\"Thread 4 updated Griffin: \" + tracker.getPerch(\"Griffin\"));\n                    }\n                    Thread.sleep(70);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 6; i++) {\n                try {\n                    Map<String, Glyph> perches = tracker.getPerches();\n                    System.out.println(\"Thread 5 viewing perches, count: \" + perches.size());\n                    Thread.sleep(80);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(2, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"\\nFinal beast perches:\");\n        tracker.getPerches().forEach((sigil, glyph) -> \n            System.out.println(sigil + \": \" + glyph));\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Delegating thread safety to a ConcurrentHashMap. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called CelestialCaravanTracker that orchestrates the havens of drift-beasts in a thread-safe nebula. The class should use a ConcurrentHashMap to catalog beast havens, where each beast is tagged by a unique String glyph and its current haven is represented by a Starlight object. Provide the following functionality: \nA constructor that embraces an initial Map of beast glyphs to Starlight objects and infuses the internal concurrent map with these values. \nA method getHavens() that unveils an unmodifiable view of the current beast havens to prevent external weaving. \nA method getHaven(String glyph) that summons the current haven of the specified beast or null if the beast does not exist. \nA method setHaven(String glyph, int shimmer, int pulse) that transforms the haven of an existing beast with the given glyph to the new coordinates (shimmer, pulse). If the beast does not exist, this method should conjure an appropriate exception such as IllegalArgumentException. \nAn alternative method getHavensAsStatic() that captures a snapshot of the current havens as an unmodifiable Map to provide a consistent view of all havens at the moment of invocation. \nEnsure that all operations are thread-safe without requiring additional synchronization in the class. Use standard Java libraries for concurrency and collections. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Starlight {\n    private final int shimmer;\n    private final int pulse;\n    \n    public Starlight(int shimmer, int pulse) {\n        this.shimmer = shimmer;\n        this.pulse = pulse;\n    }\n    \n    public int getShimmer() {\n        return shimmer;\n    }\n    \n    public int getPulse() {\n        return pulse;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Starlight{shimmer=\" + shimmer + \", pulse=\" + pulse + \"}\";\n    }\n}\n\nclass CelestialCaravanTracker {\n    private final ConcurrentHashMap<String, Starlight> beastHavens;\n    \n    public CelestialCaravanTracker(Map<String, Starlight> initialHavens) {\n        this.beastHavens = new ConcurrentHashMap<>(initialHavens);\n    }\n    \n    public Map<String, Starlight> getHavens() {\n        return Collections.unmodifiableMap(beastHavens);\n    }\n    \n    public Starlight getHaven(String glyph) {\n        return beastHavens.get(glyph);\n    }\n    \n    public void setHaven(String glyph, int shimmer, int pulse) {\n        Starlight newHaven = new Starlight(shimmer, pulse);\n        Starlight oldHaven = beastHavens.replace(glyph, newHaven);\n        if (oldHaven == null) {\n            throw new IllegalArgumentException(\"Beast with glyph '\" + glyph + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Starlight> getHavensAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastHavens));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, Starlight> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new Starlight(10, 20));\n        initialMap.put(\"beta\", new Starlight(30, 40));\n        initialMap.put(\"gamma\", new Starlight(50, 60));\n        initialMap.put(\"delta\", new Starlight(70, 80));\n        initialMap.put(\"epsilon\", new Starlight(90, 100));\n        \n        CelestialCaravanTracker tracker = new CelestialCaravanTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setHaven(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(10);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setHaven(\"beta\", i * 4, i * 5);\n                    Thread.sleep(10);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Starlight haven = tracker.getHaven(\"gamma\");\n                if (haven != null) {\n                    System.out.println(\"Gamma haven: \" + haven);\n                }\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Starlight> snapshot = tracker.getHavensAsStatic();\n                System.out.println(\"Snapshot size: \" + snapshot.size());\n                try {\n                    Thread.sleep(25);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                try {\n                    tracker.setHaven(\"delta\", i * 10, i * 11);\n                    tracker.setHaven(\"epsilon\", i * 12, i * 13);\n                    Thread.sleep(12);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final havens:\");\n        Map<String, Starlight> finalHavens = tracker.getHavens();\n        for (Map.Entry<String, Starlight> entry : finalHavens.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Starlight {\n    private final int shimmer;\n    private final int pulse;\n    \n    public Starlight(int shimmer, int pulse) {\n        this.shimmer = shimmer;\n        this.pulse = pulse;\n    }\n    \n    public int getShimmer() {\n        return shimmer;\n    }\n    \n    public int getPulse() {\n        return pulse;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Starlight{shimmer=\" + shimmer + \", pulse=\" + pulse + \"}\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Starlight starlight = (Starlight) o;\n        return shimmer == starlight.shimmer && pulse == starlight.pulse;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(shimmer, pulse);\n    }\n}\n\nclass CelestialCaravanTracker {\n    private final ConcurrentHashMap<String, Starlight> beastHavens;\n    \n    public CelestialCaravanTracker(Map<String, Starlight> initialHavens) {\n        this.beastHavens = new ConcurrentHashMap<>(initialHavens);\n    }\n    \n    public Map<String, Starlight> getHavens() {\n        return Collections.unmodifiableMap(beastHavens);\n    }\n    \n    public Starlight getHaven(String glyph) {\n        return beastHavens.get(glyph);\n    }\n    \n    public void setHaven(String glyph, int shimmer, int pulse) {\n        Starlight newStarlight = new Starlight(shimmer, pulse);\n        Starlight previous = beastHavens.replace(glyph, newStarlight);\n        if (previous == null) {\n            throw new IllegalArgumentException(\"Beast with glyph '\" + glyph + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Starlight> getHavensAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastHavens));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Starlight> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new Starlight(10, 20));\n        initialMap.put(\"beta\", new Starlight(30, 40));\n        initialMap.put(\"gamma\", new Starlight(50, 60));\n        initialMap.put(\"delta\", new Starlight(70, 80));\n        initialMap.put(\"epsilon\", new Starlight(90, 100));\n        \n        CelestialCaravanTracker tracker = new CelestialCaravanTracker(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            try {\n                tracker.setHaven(\"alpha\", 15, 25);\n                System.out.println(\"Thread 1: Updated alpha to \" + tracker.getHaven(\"alpha\"));\n            } catch (Exception e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                tracker.setHaven(\"beta\", 35, 45);\n                System.out.println(\"Thread 2: Updated beta to \" + tracker.getHaven(\"beta\"));\n            } catch (Exception e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            Map<String, Starlight> snapshot = tracker.getHavensAsStatic();\n            System.out.println(\"Thread 3: Snapshot size = \" + snapshot.size());\n        });\n        \n        executor.submit(() -> {\n            try {\n                tracker.setHaven(\"nonexistent\", 100, 200);\n            } catch (IllegalArgumentException e) {\n                System.out.println(\"Thread 4: Caught exception - \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            Map<String, Starlight> havens = tracker.getHavens();\n            System.out.println(\"Thread 5: Total havens = \" + havens.size());\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final havens:\");\n        tracker.getHavens().forEach((k, v) -> System.out.println(k + \" -> \" + v));\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Starlight {\n    private final int shimmer;\n    private final int pulse;\n    \n    public Starlight(int shimmer, int pulse) {\n        this.shimmer = shimmer;\n        this.pulse = pulse;\n    }\n    \n    public int getShimmer() {\n        return shimmer;\n    }\n    \n    public int getPulse() {\n        return pulse;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Starlight{shimmer=\" + shimmer + \", pulse=\" + pulse + \"}\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Starlight starlight = (Starlight) o;\n        return shimmer == starlight.shimmer && pulse == starlight.pulse;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(shimmer, pulse);\n    }\n}\n\nclass CelestialCaravanTracker {\n    private final ConcurrentHashMap<String, Starlight> beastHavens;\n    \n    public CelestialCaravanTracker(Map<String, Starlight> initialHavens) {\n        this.beastHavens = new ConcurrentHashMap<>(initialHavens);\n    }\n    \n    public Map<String, Starlight> getHavens() {\n        return Collections.unmodifiableMap(beastHavens);\n    }\n    \n    public Starlight getHaven(String glyph) {\n        return beastHavens.get(glyph);\n    }\n    \n    public void setHaven(String glyph, int shimmer, int pulse) {\n        Starlight newStarlight = new Starlight(shimmer, pulse);\n        Starlight oldValue = beastHavens.replace(glyph, newStarlight);\n        if (oldValue == null) {\n            throw new IllegalArgumentException(\"Beast with glyph \" + glyph + \" does not exist\");\n        }\n    }\n    \n    public Map<String, Starlight> getHavensAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastHavens));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Starlight> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new Starlight(10, 20));\n        initialMap.put(\"beta\", new Starlight(30, 40));\n        initialMap.put(\"gamma\", new Starlight(50, 60));\n        initialMap.put(\"delta\", new Starlight(70, 80));\n        initialMap.put(\"epsilon\", new Starlight(90, 100));\n        \n        CelestialCaravanTracker tracker = new CelestialCaravanTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        CountDownLatch latch = new CountDownLatch(5);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    tracker.setHaven(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(10);\n                }\n                System.out.println(\"Thread 1: Updated alpha\");\n            } catch (Exception e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Starlight haven = tracker.getHaven(\"beta\");\n                    System.out.println(\"Thread 2: beta = \" + haven);\n                    Thread.sleep(15);\n                }\n            } catch (Exception e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    Map<String, Starlight> snapshot = tracker.getHavensAsStatic();\n                    System.out.println(\"Thread 3: Snapshot size = \" + snapshot.size());\n                    Thread.sleep(20);\n                }\n            } catch (Exception e) {\n                System.out.println(\"Thread 3 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 8; i++) {\n                    tracker.setHaven(\"gamma\", 100 + i, 200 + i);\n                    tracker.setHaven(\"delta\", 300 + i, 400 + i);\n                    Thread.sleep(12);\n                }\n                System.out.println(\"Thread 4: Updated gamma and delta\");\n            } catch (Exception e) {\n                System.out.println(\"Thread 4 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(30);\n                tracker.setHaven(\"nonexistent\", 1, 2);\n            } catch (IllegalArgumentException e) {\n                System.out.println(\"Thread 5: Expected exception - \" + e.getMessage());\n            } catch (Exception e) {\n                System.out.println(\"Thread 5 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        try {\n            latch.await();\n            executor.shutdown();\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n            \n            System.out.println(\"\\nFinal state:\");\n            Map<String, Starlight> finalHavens = tracker.getHavens();\n            for (Map.Entry<String, Starlight> entry : finalHavens.entrySet()) {\n                System.out.println(entry.getKey() + \" -> \" + entry.getValue());\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            System.out.println(\"Main thread interrupted\");\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            false,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.awt.Point;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.concurrent.ConcurrentMap;\nimport java.util.Collections;\n\n/**\n* DelegatingVehicleTracker\n* Tracks vehicle locations using a thread-safe ConcurrentHashMap.\n* Modified to use explicit Threads for JPF compatibility.\n*/\npublic class DelegatingVehicleTracker {\nprivate final ConcurrentMap<String, Point> locations;\nprivate final Map<String, Point> unmodifiableMap;\n\npublic DelegatingVehicleTracker(Map<String, Point> points) {\nlocations = new ConcurrentHashMap<>(points);\nunmodifiableMap = Collections.unmodifiableMap(locations);\n}\n\npublic Map<String, Point> getLocations() {\nreturn unmodifiableMap;\n}\n\npublic Point getLocation(String id) {\nreturn locations.get(id);\n}\n\npublic void setLocation(String id, int x, int y) {\nif (locations.replace(id, new Point(x, y)) == null)\nthrow new IllegalArgumentException(\"Invalid vehicle ID: \" + id);\n}\n\npublic Map<String, Point> getLocationsAsStatic() {\nreturn Collections.unmodifiableMap(new HashMap<>(locations));\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, Point> initialLocations = new HashMap<>();\ninitialLocations.put(\"V1\", new Point(0, 0));\ninitialLocations.put(\"V2\", new Point(10, 10));\ninitialLocations.put(\"V3\", new Point(20, 20));\n\nDelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n\n// Reduce thread count and iterations to shorten JPF testing time\nThread[] threads = new Thread[2]; // fewer threads\n\nfor (int i = 0; i < 2; i++) {\nfinal int threadId = i;\nthreads[i] = new Thread(() -> {\nRandom rand = new Random();\nfor (int j = 0; j < 3; j++) { // fewer iterations\nString vehicleId = \"V\" + ((threadId % 3) + 1);\nint newX = rand.nextInt(21); // 0 to 20\nint newY = rand.nextInt(21); // 0 to 20\nSystem.out.println(\"Thread-\" + threadId + \": Setting \" + vehicleId + \" to (\" + newX + \", \" + newY + \")\");\ntracker.setLocation(vehicleId, newX, newY);\ntry {\nThread.sleep(20); // shorter sleep to speed up execution\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\nfor (Map.Entry<String, Point> entry : tracker.getLocations().entrySet()) {\nSystem.out.println(entry.getKey() + \" => \" + entry.getValue());\n}\n}\n}",
        "max_depth": "81",
        "jpf_details": [
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 57.95%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 30.05%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 33.63%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 34.05%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 31.62%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 39.23%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=55934,visited=75127,backtracked=130291,end=3615\nsearch:             maxDepth=810,constraints=22850\nchoice generators:  thread=45055 (signal=0,lock=40,sharedRef=12140,threadApi=44,reschedule=32176), data=0\nheap:               new=609602,released=1270523,maxLive=933,gcCycles=130615\ninstructions:       96176215\nmax memory:         1013MB\nloaded code:        classes=166,methods=2967\n\n====================================================== search finished",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 39.04%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 39.72%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 41.55%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 34.21%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 69.03%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=61300,visited=74975,backtracked=135470,end=368\nsearch:             maxDepth=810,constraints=30837\nchoice generators:  thread=37343 (signal=0,lock=33,sharedRef=21742,threadApi=38,reschedule=11614), data=0\nheap:               new=597200,released=773631,maxLive=938,gcCycles=136087\ninstructions:       90593709\nmax memory:         1015MB\nloaded code:        classes=166,methods=2751\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/16/25 4:43 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "no errors detected"
        ],
        "codebleu_score": [
            56.65,
            58.08,
            63.56
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Starlight {\n    private final int shimmer;\n    private final int pulse;\n    \n    public Starlight(int shimmer, int pulse) {\n        this.shimmer = shimmer;\n        this.pulse = pulse;\n    }\n    \n    public int getShimmer() {\n        return shimmer;\n    }\n    \n    public int getPulse() {\n        return pulse;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Starlight{shimmer=\" + shimmer + \", pulse=\" + pulse + \"}\";\n    }\n}\n\nclass CelestialCaravanTracker {\n    private final ConcurrentHashMap<String, Starlight> beastHavens;\n    \n    public CelestialCaravanTracker(Map<String, Starlight> initialHavens) {\n        this.beastHavens = new ConcurrentHashMap<>(initialHavens);\n    }\n    \n    public Map<String, Starlight> getHavens() {\n        return Collections.unmodifiableMap(beastHavens);\n    }\n    \n    public Starlight getHaven(String glyph) {\n        return beastHavens.get(glyph);\n    }\n    \n    public void setHaven(String glyph, int shimmer, int pulse) {\n        Starlight newHaven = new Starlight(shimmer, pulse);\n        Starlight oldHaven = beastHavens.replace(glyph, newHaven);\n        if (oldHaven == null) {\n            throw new IllegalArgumentException(\"Beast with glyph '\" + glyph + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Starlight> getHavensAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastHavens));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, Starlight> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new Starlight(10, 20));\n        initialMap.put(\"beta\", new Starlight(30, 40));\n        initialMap.put(\"gamma\", new Starlight(50, 60));\n        initialMap.put(\"delta\", new Starlight(70, 80));\n        initialMap.put(\"epsilon\", new Starlight(90, 100));\n        \n        CelestialCaravanTracker tracker = new CelestialCaravanTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setHaven(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(10);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setHaven(\"beta\", i * 4, i * 5);\n                    Thread.sleep(10);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Starlight haven = tracker.getHaven(\"gamma\");\n                if (haven != null) {\n                    System.out.println(\"Gamma haven: \" + haven);\n                }\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Starlight> snapshot = tracker.getHavensAsStatic();\n                System.out.println(\"Snapshot size: \" + snapshot.size());\n                try {\n                    Thread.sleep(25);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                try {\n                    tracker.setHaven(\"delta\", i * 10, i * 11);\n                    tracker.setHaven(\"epsilon\", i * 12, i * 13);\n                    Thread.sleep(12);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final havens:\");\n        Map<String, Starlight> finalHavens = tracker.getHavens();\n        for (Map.Entry<String, Starlight> entry : finalHavens.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Starlight {\n    private final int shimmer;\n    private final int pulse;\n    \n    public Starlight(int shimmer, int pulse) {\n        this.shimmer = shimmer;\n        this.pulse = pulse;\n    }\n    \n    public int getShimmer() {\n        return shimmer;\n    }\n    \n    public int getPulse() {\n        return pulse;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Starlight{shimmer=\" + shimmer + \", pulse=\" + pulse + \"}\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Starlight starlight = (Starlight) o;\n        return shimmer == starlight.shimmer && pulse == starlight.pulse;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(shimmer, pulse);\n    }\n}\n\nclass CelestialCaravanTracker {\n    private final ConcurrentHashMap<String, Starlight> beastHavens;\n    \n    public CelestialCaravanTracker(Map<String, Starlight> initialHavens) {\n        this.beastHavens = new ConcurrentHashMap<>(initialHavens);\n    }\n    \n    public Map<String, Starlight> getHavens() {\n        return Collections.unmodifiableMap(beastHavens);\n    }\n    \n    public Starlight getHaven(String glyph) {\n        return beastHavens.get(glyph);\n    }\n    \n    public void setHaven(String glyph, int shimmer, int pulse) {\n        Starlight newStarlight = new Starlight(shimmer, pulse);\n        Starlight previous = beastHavens.replace(glyph, newStarlight);\n        if (previous == null) {\n            throw new IllegalArgumentException(\"Beast with glyph '\" + glyph + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Starlight> getHavensAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastHavens));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Starlight> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new Starlight(10, 20));\n        initialMap.put(\"beta\", new Starlight(30, 40));\n        initialMap.put(\"gamma\", new Starlight(50, 60));\n        initialMap.put(\"delta\", new Starlight(70, 80));\n        initialMap.put(\"epsilon\", new Starlight(90, 100));\n        \n        CelestialCaravanTracker tracker = new CelestialCaravanTracker(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            try {\n                tracker.setHaven(\"alpha\", 15, 25);\n                System.out.println(\"Thread 1: Updated alpha to \" + tracker.getHaven(\"alpha\"));\n            } catch (Exception e) {\n                System.out.println(\"Thread 1: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                tracker.setHaven(\"beta\", 35, 45);\n                System.out.println(\"Thread 2: Updated beta to \" + tracker.getHaven(\"beta\"));\n            } catch (Exception e) {\n                System.out.println(\"Thread 2: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            Map<String, Starlight> snapshot = tracker.getHavensAsStatic();\n            System.out.println(\"Thread 3: Snapshot size = \" + snapshot.size());\n        });\n        \n        executor.submit(() -> {\n            try {\n                tracker.setHaven(\"nonexistent\", 100, 200);\n            } catch (IllegalArgumentException e) {\n                System.out.println(\"Thread 4: Caught exception - \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            Map<String, Starlight> havens = tracker.getHavens();\n            System.out.println(\"Thread 5: Total havens = \" + havens.size());\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final havens:\");\n        tracker.getHavens().forEach((k, v) -> System.out.println(k + \" -> \" + v));\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Starlight {\n    private final int shimmer;\n    private final int pulse;\n    \n    public Starlight(int shimmer, int pulse) {\n        this.shimmer = shimmer;\n        this.pulse = pulse;\n    }\n    \n    public int getShimmer() {\n        return shimmer;\n    }\n    \n    public int getPulse() {\n        return pulse;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Starlight{shimmer=\" + shimmer + \", pulse=\" + pulse + \"}\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Starlight starlight = (Starlight) o;\n        return shimmer == starlight.shimmer && pulse == starlight.pulse;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(shimmer, pulse);\n    }\n}\n\nclass CelestialCaravanTracker {\n    private final ConcurrentHashMap<String, Starlight> beastHavens;\n    \n    public CelestialCaravanTracker(Map<String, Starlight> initialHavens) {\n        this.beastHavens = new ConcurrentHashMap<>(initialHavens);\n    }\n    \n    public Map<String, Starlight> getHavens() {\n        return Collections.unmodifiableMap(beastHavens);\n    }\n    \n    public Starlight getHaven(String glyph) {\n        return beastHavens.get(glyph);\n    }\n    \n    public void setHaven(String glyph, int shimmer, int pulse) {\n        Starlight newStarlight = new Starlight(shimmer, pulse);\n        Starlight oldValue = beastHavens.replace(glyph, newStarlight);\n        if (oldValue == null) {\n            throw new IllegalArgumentException(\"Beast with glyph \" + glyph + \" does not exist\");\n        }\n    }\n    \n    public Map<String, Starlight> getHavensAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(beastHavens));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Starlight> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new Starlight(10, 20));\n        initialMap.put(\"beta\", new Starlight(30, 40));\n        initialMap.put(\"gamma\", new Starlight(50, 60));\n        initialMap.put(\"delta\", new Starlight(70, 80));\n        initialMap.put(\"epsilon\", new Starlight(90, 100));\n        \n        CelestialCaravanTracker tracker = new CelestialCaravanTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        CountDownLatch latch = new CountDownLatch(5);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    tracker.setHaven(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(10);\n                }\n                System.out.println(\"Thread 1: Updated alpha\");\n            } catch (Exception e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Starlight haven = tracker.getHaven(\"beta\");\n                    System.out.println(\"Thread 2: beta = \" + haven);\n                    Thread.sleep(15);\n                }\n            } catch (Exception e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    Map<String, Starlight> snapshot = tracker.getHavensAsStatic();\n                    System.out.println(\"Thread 3: Snapshot size = \" + snapshot.size());\n                    Thread.sleep(20);\n                }\n            } catch (Exception e) {\n                System.out.println(\"Thread 3 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 8; i++) {\n                    tracker.setHaven(\"gamma\", 100 + i, 200 + i);\n                    tracker.setHaven(\"delta\", 300 + i, 400 + i);\n                    Thread.sleep(12);\n                }\n                System.out.println(\"Thread 4: Updated gamma and delta\");\n            } catch (Exception e) {\n                System.out.println(\"Thread 4 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(30);\n                tracker.setHaven(\"nonexistent\", 1, 2);\n            } catch (IllegalArgumentException e) {\n                System.out.println(\"Thread 5: Expected exception - \" + e.getMessage());\n            } catch (Exception e) {\n                System.out.println(\"Thread 5 error: \" + e.getMessage());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        try {\n            latch.await();\n            executor.shutdown();\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n            \n            System.out.println(\"\\nFinal state:\");\n            Map<String, Starlight> finalHavens = tracker.getHavens();\n            for (Map.Entry<String, Starlight> entry : finalHavens.entrySet()) {\n                System.out.println(entry.getKey() + \" -> \" + entry.getValue());\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            System.out.println(\"Main thread interrupted\");\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Delegating thread safety to a ConcurrentHashMap. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called PhantomGliderTracker that monitors the perches of whispering gliders in a thread-safe dream-realm. The class should use a ConcurrentHashMap to archive glider perches, where each glider is identified by a unique String rune and its current perch is represented by a Nimbus object. Provide the following functionality: \n\nA constructor that accepts an initial Map of glider runes to Nimbus objects and populates the internal concurrent map with these values. \nA method getPerches() that returns an unmodifiable view of the current glider perches to prevent external interference. \nA method getPerch(String rune) that retrieves the current perch of the specified glider or null if the glider does not exist. \nA method setPerch(String rune, int glow, int drift) that relocates the perch of an existing glider with the given rune to the new coordinates (glow, drift). If the glider does not exist, this method should raise an appropriate exception such as IllegalArgumentException. \nAn alternative method getPerchesAsStatic() that captures a snapshot of the current perches as an unmodifiable Map to provide a consistent view of all perches at the moment of invocation. \nEnsure that all operations are thread-safe without requiring additional synchronization in the class. Use standard Java libraries for concurrency and collections. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Nimbus {\n    private final int glow;\n    private final int drift;\n    \n    public Nimbus(int glow, int drift) {\n        this.glow = glow;\n        this.drift = drift;\n    }\n    \n    public int getGlow() {\n        return glow;\n    }\n    \n    public int getDrift() {\n        return drift;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Nimbus{glow=\" + glow + \", drift=\" + drift + \"}\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Nimbus nimbus = (Nimbus) obj;\n        return glow == nimbus.glow && drift == nimbus.drift;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(glow, drift);\n    }\n}\n\nclass PhantomGliderTracker {\n    private final ConcurrentHashMap<String, Nimbus> gliderPerches;\n    \n    public PhantomGliderTracker(Map<String, Nimbus> initialPerches) {\n        this.gliderPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Nimbus> getPerches() {\n        return Collections.unmodifiableMap(gliderPerches);\n    }\n    \n    public Nimbus getPerch(String rune) {\n        return gliderPerches.get(rune);\n    }\n    \n    public void setPerch(String rune, int glow, int drift) {\n        Nimbus newNimbus = new Nimbus(glow, drift);\n        Nimbus oldNimbus = gliderPerches.replace(rune, newNimbus);\n        if (oldNimbus == null) {\n            throw new IllegalArgumentException(\"Glider with rune '\" + rune + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Nimbus> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(gliderPerches));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, Nimbus> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new Nimbus(10, 20));\n        initialMap.put(\"beta\", new Nimbus(30, 40));\n        initialMap.put(\"gamma\", new Nimbus(50, 60));\n        initialMap.put(\"delta\", new Nimbus(70, 80));\n        initialMap.put(\"epsilon\", new Nimbus(90, 100));\n        \n        PhantomGliderTracker tracker = new PhantomGliderTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"beta\", i * 4, i * 5);\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Nimbus perch = tracker.getPerch(\"gamma\");\n                if (perch != null) {\n                    System.out.println(\"Gamma perch: \" + perch);\n                }\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Nimbus> snapshot = tracker.getPerchesAsStatic();\n                System.out.println(\"Snapshot size: \" + snapshot.size());\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"delta\", i * 6, i * 7);\n                    tracker.setPerch(\"epsilon\", i * 8, i * 9);\n                    Thread.sleep(12);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final perches:\");\n        Map<String, Nimbus> finalPerches = tracker.getPerches();\n        for (Map.Entry<String, Nimbus> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Nimbus {\n    private final int glow;\n    private final int drift;\n    \n    public Nimbus(int glow, int drift) {\n        this.glow = glow;\n        this.drift = drift;\n    }\n    \n    public int getGlow() {\n        return glow;\n    }\n    \n    public int getDrift() {\n        return drift;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Nimbus{glow=\" + glow + \", drift=\" + drift + \"}\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Nimbus nimbus = (Nimbus) o;\n        return glow == nimbus.glow && drift == nimbus.drift;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(glow, drift);\n    }\n}\n\nclass PhantomGliderTracker {\n    private final ConcurrentHashMap<String, Nimbus> gliderPerches;\n    \n    public PhantomGliderTracker(Map<String, Nimbus> initialPerches) {\n        this.gliderPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Nimbus> getPerches() {\n        return Collections.unmodifiableMap(gliderPerches);\n    }\n    \n    public Nimbus getPerch(String rune) {\n        return gliderPerches.get(rune);\n    }\n    \n    public void setPerch(String rune, int glow, int drift) {\n        if (!gliderPerches.containsKey(rune)) {\n            throw new IllegalArgumentException(\"Glider with rune \" + rune + \" does not exist\");\n        }\n        gliderPerches.put(rune, new Nimbus(glow, drift));\n    }\n    \n    public Map<String, Nimbus> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(gliderPerches));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, Nimbus> initialPerches = new HashMap<>();\n        initialPerches.put(\"alpha\", new Nimbus(10, 20));\n        initialPerches.put(\"beta\", new Nimbus(30, 40));\n        initialPerches.put(\"gamma\", new Nimbus(50, 60));\n        initialPerches.put(\"delta\", new Nimbus(70, 80));\n        initialPerches.put(\"epsilon\", new Nimbus(90, 100));\n        \n        PhantomGliderTracker tracker = new PhantomGliderTracker(initialPerches);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"beta\", i * 4, i * 5);\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Nimbus perch = tracker.getPerch(\"gamma\");\n                if (perch != null) {\n                    tracker.setPerch(\"gamma\", perch.getGlow() + 1, perch.getDrift() + 1);\n                }\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Nimbus> snapshot = tracker.getPerchesAsStatic();\n                System.out.println(\"Snapshot \" + i + \": \" + snapshot.size() + \" gliders\");\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Nimbus> perches = tracker.getPerches();\n                for (Map.Entry<String, Nimbus> entry : perches.entrySet()) {\n                    System.out.println(\"Glider \" + entry.getKey() + \" at \" + entry.getValue());\n                }\n                try {\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final perches:\");\n        Map<String, Nimbus> finalPerches = tracker.getPerchesAsStatic();\n        for (Map.Entry<String, Nimbus> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PhantomGliderTracker {\n    private final ConcurrentHashMap<String, Nimbus> gliderPerches;\n    \n    public PhantomGliderTracker(Map<String, Nimbus> initialPerches) {\n        this.gliderPerches = new ConcurrentHashMap<>();\n        if (initialPerches != null) {\n            this.gliderPerches.putAll(initialPerches);\n        }\n    }\n    \n    public Map<String, Nimbus> getPerches() {\n        return Collections.unmodifiableMap(gliderPerches);\n    }\n    \n    public Nimbus getPerch(String rune) {\n        return gliderPerches.get(rune);\n    }\n    \n    public void setPerch(String rune, int glow, int drift) {\n        Nimbus currentPerch = gliderPerches.get(rune);\n        if (currentPerch == null) {\n            throw new IllegalArgumentException(\"Glider with rune \" + rune + \" does not exist\");\n        }\n        gliderPerches.put(rune, new Nimbus(glow, drift));\n    }\n    \n    public Map<String, Nimbus> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(gliderPerches));\n    }\n    \n    public static void main(String[] args) {\n        Map<String, Nimbus> initialData = new HashMap<>();\n        initialData.put(\"alpha\", new Nimbus(10, 20));\n        initialData.put(\"beta\", new Nimbus(30, 40));\n        initialData.put(\"gamma\", new Nimbus(50, 60));\n        initialData.put(\"delta\", new Nimbus(70, 80));\n        initialData.put(\"epsilon\", new Nimbus(90, 100));\n        \n        PhantomGliderTracker tracker = new PhantomGliderTracker(initialData);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(50);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"beta\", i * 4, i * 5);\n                    Thread.sleep(60);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Nimbus perch = tracker.getPerch(\"gamma\");\n                if (perch != null) {\n                    System.out.println(\"Gamma perch: \" + perch);\n                }\n                try {\n                    Thread.sleep(70);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Nimbus> snapshot = tracker.getPerchesAsStatic();\n                System.out.println(\"Snapshot size: \" + snapshot.size());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                try {\n                    tracker.setPerch(\"delta\", i * 6, i * 7);\n                    tracker.setPerch(\"epsilon\", i * 8, i * 9);\n                    Thread.sleep(80);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"Final perches:\");\n        Map<String, Nimbus> finalPerches = tracker.getPerches();\n        for (Map.Entry<String, Nimbus> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass Nimbus {\n    private final int glow;\n    private final int drift;\n    \n    public Nimbus(int glow, int drift) {\n        this.glow = glow;\n        this.drift = drift;\n    }\n    \n    public int getGlow() {\n        return glow;\n    }\n    \n    public int getDrift() {\n        return drift;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Nimbus[glow=\" + glow + \", drift=\" + drift + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Nimbus nimbus = (Nimbus) obj;\n        return glow == nimbus.glow && drift == nimbus.drift;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(glow, drift);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.awt.Point;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.concurrent.ConcurrentMap;\nimport java.util.Collections;\n\n/**\n* DelegatingVehicleTracker\n* Tracks vehicle locations using a thread-safe ConcurrentHashMap.\n* Modified to use explicit Threads for JPF compatibility.\n*/\npublic class DelegatingVehicleTracker {\nprivate final ConcurrentMap<String, Point> locations;\nprivate final Map<String, Point> unmodifiableMap;\n\npublic DelegatingVehicleTracker(Map<String, Point> points) {\nlocations = new ConcurrentHashMap<>(points);\nunmodifiableMap = Collections.unmodifiableMap(locations);\n}\n\npublic Map<String, Point> getLocations() {\nreturn unmodifiableMap;\n}\n\npublic Point getLocation(String id) {\nreturn locations.get(id);\n}\n\npublic void setLocation(String id, int x, int y) {\nif (locations.replace(id, new Point(x, y)) == null)\nthrow new IllegalArgumentException(\"Invalid vehicle ID: \" + id);\n}\n\npublic Map<String, Point> getLocationsAsStatic() {\nreturn Collections.unmodifiableMap(new HashMap<>(locations));\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, Point> initialLocations = new HashMap<>();\ninitialLocations.put(\"V1\", new Point(0, 0));\ninitialLocations.put(\"V2\", new Point(10, 10));\ninitialLocations.put(\"V3\", new Point(20, 20));\n\nDelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n\n// Reduce thread count and iterations to shorten JPF testing time\nThread[] threads = new Thread[2]; // fewer threads\n\nfor (int i = 0; i < 2; i++) {\nfinal int threadId = i;\nthreads[i] = new Thread(() -> {\nRandom rand = new Random();\nfor (int j = 0; j < 3; j++) { // fewer iterations\nString vehicleId = \"V\" + ((threadId % 3) + 1);\nint newX = rand.nextInt(21); // 0 to 20\nint newY = rand.nextInt(21); // 0 to 20\nSystem.out.println(\"Thread-\" + threadId + \": Setting \" + vehicleId + \" to (\" + newX + \", \" + newY + \")\");\ntracker.setLocation(vehicleId, newX, newY);\ntry {\nThread.sleep(20); // shorter sleep to speed up execution\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\nfor (Map.Entry<String, Point> entry : tracker.getLocations().entrySet()) {\nSystem.out.println(entry.getKey() + \" => \" + entry.getValue());\n}\n}\n}",
        "max_depth": "81",
        "jpf_details": [
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 58.03%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 29.66%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 32.85%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 33.65%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 31.98%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 39.77%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=57163,visited=76900,backtracked=133283,end=3668\nsearch:             maxDepth=810,constraints=23253\nchoice generators:  thread=46119 (signal=0,lock=83,sharedRef=12927,threadApi=58,reschedule=32386), data=0\nheap:               new=615966,released=1284009,maxLive=933,gcCycles=133461\ninstructions:       97015180\nmax memory:         1013MB\nloaded code:        classes=166,methods=2969\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 48.68%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 58.42%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 70.10%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 70.08%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=86442,visited=197572,backtracked=283250,end=0\nsearch:             maxDepth=810,constraints=5115\nchoice generators:  thread=84912 (signal=0,lock=38,sharedRef=84230,threadApi=635,reschedule=0), data=0\nheap:               new=153339,released=123181,maxLive=937,gcCycles=245355\ninstructions:       12866350\nmax memory:         1020MB\nloaded code:        classes=160,methods=2926\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.52%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.98%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.98%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.98%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.98%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.98%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=86473,visited=118108,backtracked=203771,end=0\nsearch:             maxDepth=810,constraints=95307\nchoice generators:  thread=34806 (signal=0,lock=55,sharedRef=31199,threadApi=44,reschedule=38), data=0\nheap:               new=127556,released=53740,maxLive=903,gcCycles=204196\ninstructions:       36284956\nmax memory:         1018MB\nloaded code:        classes=159,methods=2750\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            63.89,
            63.41,
            58.39
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Nimbus {\n    private final int glow;\n    private final int drift;\n    \n    public Nimbus(int glow, int drift) {\n        this.glow = glow;\n        this.drift = drift;\n    }\n    \n    public int getGlow() {\n        return glow;\n    }\n    \n    public int getDrift() {\n        return drift;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Nimbus{glow=\" + glow + \", drift=\" + drift + \"}\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Nimbus nimbus = (Nimbus) obj;\n        return glow == nimbus.glow && drift == nimbus.drift;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(glow, drift);\n    }\n}\n\nclass PhantomGliderTracker {\n    private final ConcurrentHashMap<String, Nimbus> gliderPerches;\n    \n    public PhantomGliderTracker(Map<String, Nimbus> initialPerches) {\n        this.gliderPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Nimbus> getPerches() {\n        return Collections.unmodifiableMap(gliderPerches);\n    }\n    \n    public Nimbus getPerch(String rune) {\n        return gliderPerches.get(rune);\n    }\n    \n    public void setPerch(String rune, int glow, int drift) {\n        Nimbus newNimbus = new Nimbus(glow, drift);\n        Nimbus oldNimbus = gliderPerches.replace(rune, newNimbus);\n        if (oldNimbus == null) {\n            throw new IllegalArgumentException(\"Glider with rune '\" + rune + \"' does not exist\");\n        }\n    }\n    \n    public Map<String, Nimbus> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(gliderPerches));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, Nimbus> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new Nimbus(10, 20));\n        initialMap.put(\"beta\", new Nimbus(30, 40));\n        initialMap.put(\"gamma\", new Nimbus(50, 60));\n        initialMap.put(\"delta\", new Nimbus(70, 80));\n        initialMap.put(\"epsilon\", new Nimbus(90, 100));\n        \n        PhantomGliderTracker tracker = new PhantomGliderTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"beta\", i * 4, i * 5);\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Nimbus perch = tracker.getPerch(\"gamma\");\n                if (perch != null) {\n                    System.out.println(\"Gamma perch: \" + perch);\n                }\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Nimbus> snapshot = tracker.getPerchesAsStatic();\n                System.out.println(\"Snapshot size: \" + snapshot.size());\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"delta\", i * 6, i * 7);\n                    tracker.setPerch(\"epsilon\", i * 8, i * 9);\n                    Thread.sleep(12);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final perches:\");\n        Map<String, Nimbus> finalPerches = tracker.getPerches();\n        for (Map.Entry<String, Nimbus> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass Nimbus {\n    private final int glow;\n    private final int drift;\n    \n    public Nimbus(int glow, int drift) {\n        this.glow = glow;\n        this.drift = drift;\n    }\n    \n    public int getGlow() {\n        return glow;\n    }\n    \n    public int getDrift() {\n        return drift;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Nimbus{glow=\" + glow + \", drift=\" + drift + \"}\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Nimbus nimbus = (Nimbus) o;\n        return glow == nimbus.glow && drift == nimbus.drift;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(glow, drift);\n    }\n}\n\nclass PhantomGliderTracker {\n    private final ConcurrentHashMap<String, Nimbus> gliderPerches;\n    \n    public PhantomGliderTracker(Map<String, Nimbus> initialPerches) {\n        this.gliderPerches = new ConcurrentHashMap<>(initialPerches);\n    }\n    \n    public Map<String, Nimbus> getPerches() {\n        return Collections.unmodifiableMap(gliderPerches);\n    }\n    \n    public Nimbus getPerch(String rune) {\n        return gliderPerches.get(rune);\n    }\n    \n    public void setPerch(String rune, int glow, int drift) {\n        if (!gliderPerches.containsKey(rune)) {\n            throw new IllegalArgumentException(\"Glider with rune \" + rune + \" does not exist\");\n        }\n        gliderPerches.put(rune, new Nimbus(glow, drift));\n    }\n    \n    public Map<String, Nimbus> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(gliderPerches));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, Nimbus> initialPerches = new HashMap<>();\n        initialPerches.put(\"alpha\", new Nimbus(10, 20));\n        initialPerches.put(\"beta\", new Nimbus(30, 40));\n        initialPerches.put(\"gamma\", new Nimbus(50, 60));\n        initialPerches.put(\"delta\", new Nimbus(70, 80));\n        initialPerches.put(\"epsilon\", new Nimbus(90, 100));\n        \n        PhantomGliderTracker tracker = new PhantomGliderTracker(initialPerches);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"beta\", i * 4, i * 5);\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Nimbus perch = tracker.getPerch(\"gamma\");\n                if (perch != null) {\n                    tracker.setPerch(\"gamma\", perch.getGlow() + 1, perch.getDrift() + 1);\n                }\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Nimbus> snapshot = tracker.getPerchesAsStatic();\n                System.out.println(\"Snapshot \" + i + \": \" + snapshot.size() + \" gliders\");\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Nimbus> perches = tracker.getPerches();\n                for (Map.Entry<String, Nimbus> entry : perches.entrySet()) {\n                    System.out.println(\"Glider \" + entry.getKey() + \" at \" + entry.getValue());\n                }\n                try {\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final perches:\");\n        Map<String, Nimbus> finalPerches = tracker.getPerchesAsStatic();\n        for (Map.Entry<String, Nimbus> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class PhantomGliderTracker {\n    private final ConcurrentHashMap<String, Nimbus> gliderPerches;\n    \n    public PhantomGliderTracker(Map<String, Nimbus> initialPerches) {\n        this.gliderPerches = new ConcurrentHashMap<>();\n        if (initialPerches != null) {\n            this.gliderPerches.putAll(initialPerches);\n        }\n    }\n    \n    public Map<String, Nimbus> getPerches() {\n        return Collections.unmodifiableMap(gliderPerches);\n    }\n    \n    public Nimbus getPerch(String rune) {\n        return gliderPerches.get(rune);\n    }\n    \n    public void setPerch(String rune, int glow, int drift) {\n        Nimbus currentPerch = gliderPerches.get(rune);\n        if (currentPerch == null) {\n            throw new IllegalArgumentException(\"Glider with rune \" + rune + \" does not exist\");\n        }\n        gliderPerches.put(rune, new Nimbus(glow, drift));\n    }\n    \n    public Map<String, Nimbus> getPerchesAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(gliderPerches));\n    }\n    \n    public static void main(String[] args) {\n        Map<String, Nimbus> initialData = new HashMap<>();\n        initialData.put(\"alpha\", new Nimbus(10, 20));\n        initialData.put(\"beta\", new Nimbus(30, 40));\n        initialData.put(\"gamma\", new Nimbus(50, 60));\n        initialData.put(\"delta\", new Nimbus(70, 80));\n        initialData.put(\"epsilon\", new Nimbus(90, 100));\n        \n        PhantomGliderTracker tracker = new PhantomGliderTracker(initialData);\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"alpha\", i * 2, i * 3);\n                    Thread.sleep(50);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setPerch(\"beta\", i * 4, i * 5);\n                    Thread.sleep(60);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Nimbus perch = tracker.getPerch(\"gamma\");\n                if (perch != null) {\n                    System.out.println(\"Gamma perch: \" + perch);\n                }\n                try {\n                    Thread.sleep(70);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Nimbus> snapshot = tracker.getPerchesAsStatic();\n                System.out.println(\"Snapshot size: \" + snapshot.size());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                try {\n                    tracker.setPerch(\"delta\", i * 6, i * 7);\n                    tracker.setPerch(\"epsilon\", i * 8, i * 9);\n                    Thread.sleep(80);\n                } catch (Exception e) {\n                    e.printStackTrace();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"Final perches:\");\n        Map<String, Nimbus> finalPerches = tracker.getPerches();\n        for (Map.Entry<String, Nimbus> entry : finalPerches.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass Nimbus {\n    private final int glow;\n    private final int drift;\n    \n    public Nimbus(int glow, int drift) {\n        this.glow = glow;\n        this.drift = drift;\n    }\n    \n    public int getGlow() {\n        return glow;\n    }\n    \n    public int getDrift() {\n        return drift;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Nimbus[glow=\" + glow + \", drift=\" + drift + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Nimbus nimbus = (Nimbus) obj;\n        return glow == nimbus.glow && drift == nimbus.drift;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(glow, drift);\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using FutureTask to preload data that is needed later. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class called DreamWeaver that simulates the summoning of visions using a separate thread. The class should use a FutureTask to manifest the visions asynchronously and provide two main operations: a method to ignite the background task and another to capture the result of the task when needed. The class should include: \nA method Vision loadVision() which enacts vision creation and may throw a custom exception called VisionCastException. \nA FutureTask that envelops a Callable to invoke the loadVision method in the background. A dedicated Thread instance to pilot the FutureTask. \nA start() method to commence the execution of the background task. A get() method that retrieves the manifested Vision and propagates any exceptions thrown during the summoning process, including properly handling and rethrowing them (e.g., wrapping unexpected exceptions using a utility-like approach). \n\nAlso define: \nAn interface Vision as a placeholder for the manifested data type. \nA custom exception class VisionCastException that extends Exception. \n\nEnsure the code is structured to be non-blocking during vision summoning but pauses only when retrieving the result via get(), and correctly handles error propagation from the background task. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Vision {\n    String getData();\n}\n\nclass VisionCastException extends Exception {\n    public VisionCastException(String message) {\n        super(message);\n    }\n    \n    public VisionCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass DreamWeaver {\n    private FutureTask<Vision> futureTask;\n    private Thread workerThread;\n    \n    public DreamWeaver() {\n        Callable<Vision> callable = new Callable<Vision>() {\n            @Override\n            public Vision call() throws Exception {\n                return loadVision();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n        this.workerThread = new Thread(futureTask);\n    }\n    \n    private Vision loadVision() throws VisionCastException {\n        try {\n            Thread.sleep(1000);\n            if (Math.random() > 0.5) {\n                throw new VisionCastException(\"Failed to manifest vision\");\n            }\n            return new Vision() {\n                @Override\n                public String getData() {\n                    return \"Mystical Vision Manifested\";\n                }\n            };\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread.start();\n    }\n    \n    public Vision get() throws VisionCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision retrieval interrupted\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof VisionCastException) {\n                throw (VisionCastException) cause;\n            } else {\n                throw new VisionCastException(\"Unexpected error during vision summoning\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        DreamWeaver dreamWeaver = new DreamWeaver();\n        \n        System.out.println(\"Starting vision summoning...\");\n        dreamWeaver.start();\n        \n        System.out.println(\"Doing other work while vision is being summoned...\");\n        \n        try {\n            Thread.sleep(500);\n            System.out.println(\"Still working...\");\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        try {\n            System.out.println(\"Attempting to capture the vision...\");\n            Vision vision = dreamWeaver.get();\n            System.out.println(\"Vision captured: \" + vision.getData());\n        } catch (VisionCastException e) {\n            System.out.println(\"Failed to capture vision: \" + e.getMessage());\n        }\n    }\n}",
            "import java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Vision {\n    String getData();\n}\n\nclass VisionCastException extends Exception {\n    public VisionCastException(String message) {\n        super(message);\n    }\n    \n    public VisionCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConcreteVision implements Vision {\n    private final String data;\n    \n    public ConcreteVision(String data) {\n        this.data = data;\n    }\n    \n    public String getData() {\n        return data;\n    }\n}\n\nclass DreamWeaver {\n    private FutureTask<Vision> futureTask;\n    private Thread workerThread;\n    \n    public DreamWeaver() {\n        Callable<Vision> callable = new Callable<Vision>() {\n            @Override\n            public Vision call() throws Exception {\n                return loadVision();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n        this.workerThread = new Thread(futureTask);\n    }\n    \n    private Vision loadVision() throws VisionCastException {\n        try {\n            Thread.sleep(1000);\n            if (Math.random() < 0.3) {\n                throw new VisionCastException(\"Vision manifestation failed\");\n            }\n            return new ConcreteVision(\"Mystical vision data: \" + System.currentTimeMillis());\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread.start();\n    }\n    \n    public Vision get() throws VisionCastException {\n        try {\n            return futureTask.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof VisionCastException) {\n                throw (VisionCastException) cause;\n            } else {\n                throw new VisionCastException(\"Unexpected error during vision summoning\", cause);\n            }\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision retrieval interrupted\", e);\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        DreamWeaver dreamWeaver = new DreamWeaver();\n        \n        System.out.println(\"Starting vision summoning...\");\n        dreamWeaver.start();\n        \n        System.out.println(\"Doing other work while vision is being summoned...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Now retrieving the vision...\");\n        try {\n            Vision vision = dreamWeaver.get();\n            System.out.println(\"Vision received: \" + vision.getData());\n        } catch (VisionCastException e) {\n            System.err.println(\"Failed to retrieve vision: \" + e.getMessage());\n            if (e.getCause() != null) {\n                System.err.println(\"Cause: \" + e.getCause().getMessage());\n            }\n        }\n    }\n}",
            "import java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Vision {\n    String getData();\n}\n\nclass VisionCastException extends Exception {\n    public VisionCastException(String message) {\n        super(message);\n    }\n    \n    public VisionCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass DreamWeaver {\n    private FutureTask<Vision> futureTask;\n    private Thread workerThread;\n    \n    public DreamWeaver() {\n        Callable<Vision> callable = new Callable<Vision>() {\n            @Override\n            public Vision call() throws Exception {\n                return loadVision();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n        this.workerThread = new Thread(futureTask);\n    }\n    \n    private Vision loadVision() throws VisionCastException {\n        try {\n            Thread.sleep(1000);\n            if (Math.random() < 0.3) {\n                throw new VisionCastException(\"Failed to manifest vision\");\n            }\n            return new Vision() {\n                @Override\n                public String getData() {\n                    return \"Mystical Vision Manifested\";\n                }\n            };\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread.start();\n    }\n    \n    public Vision get() throws VisionCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision retrieval interrupted\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof VisionCastException) {\n                throw (VisionCastException) cause;\n            } else {\n                throw new VisionCastException(\"Unexpected error during vision summoning\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        DreamWeaver dreamWeaver = new DreamWeaver();\n        \n        System.out.println(\"Starting vision summoning...\");\n        dreamWeaver.start();\n        \n        System.out.println(\"Doing other work while vision is being summoned...\");\n        \n        try {\n            Thread.sleep(500);\n            System.out.println(\"Still working...\");\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        try {\n            System.out.println(\"Attempting to capture the vision...\");\n            Vision vision = dreamWeaver.get();\n            System.out.println(\"Vision captured: \" + vision.getData());\n        } catch (VisionCastException e) {\n            System.err.println(\"Failed to capture vision: \" + e.getMessage());\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.*;\n\n/**\n* Preloader\n*\n* Using FutureTask to preload data that is needed later\n*\n* @author Brian Goetz and Tim Peierls\n*/\npublic class Preloader {\n// Simulate product information loading\nProductInfo loadProductInfo() throws DataLoadException {\ntry {\nThread.sleep(2000); // Simulate loading delay\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\nthrow new DataLoadException();\n}\nreturn new ProductInfoImpl(\"Awesome Product\", 99.99);\n}\n\nprivate final FutureTask<ProductInfo> future =\nnew FutureTask<>(new Callable<ProductInfo>() {\npublic ProductInfo call() throws DataLoadException {\nreturn loadProductInfo();\n}\n});\nprivate final Thread thread = new Thread(future);\n\npublic void start() {\nthread.start();\n}\n\npublic ProductInfo get() throws DataLoadException, InterruptedException {\ntry {\nreturn future.get();\n} catch (ExecutionException e) {\nThrowable cause = e.getCause();\nif (cause instanceof DataLoadException)\nthrow (DataLoadException) cause;\nelse\nthrow LaunderThrowable.launderThrowable(cause);\n}\n}\n\ninterface ProductInfo {\nString getName();\ndouble getPrice();\n}\n\nstatic class ProductInfoImpl implements ProductInfo {\nprivate final String name;\nprivate final double price;\n\npublic ProductInfoImpl(String name, double price) {\nthis.name = name;\nthis.price = price;\n}\n\npublic String getName() {\nreturn name;\n}\n\npublic double getPrice() {\nreturn price;\n}\n\n@Override\npublic String toString() {\nreturn \"ProductInfo{name='\" + name + \"', price=\" + price + \"}\";\n}\n}\n\n// Utility class: for throwing unchecked exceptions\nstatic class LaunderThrowable {\nstatic RuntimeException launderThrowable(Throwable t) {\nif (t instanceof RuntimeException)\nreturn (RuntimeException) t;\nelse if (t instanceof Error)\nthrow (Error) t;\nelse\nthrow new IllegalStateException(\"Not unchecked\", t);\n}\n}\n\n// Main entry point\npublic static void main(String[] args) {\nSystem.out.println(\"Starting preloader...\");\nPreloader preloader = new Preloader();\npreloader.start();\n\ntry {\nSystem.out.println(\"Doing something else in the main thread...\");\nThread.sleep(1000);\n\nSystem.out.println(\"Waiting for product info...\");\nProductInfo productInfo = preloader.get();\nSystem.out.println(\"Loaded product: \" + productInfo);\n} catch (DataLoadException | InterruptedException e) {\ne.printStackTrace();\n}\n}\n}\n\nclass DataLoadException extends Exception {\npublic DataLoadException() {\nsuper(\"Failed to load product data.\");\n}\n}",
        "max_depth": "36",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 46.81%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.31%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=893,visited=707,backtracked=1600,end=138\nsearch:             maxDepth=42,constraints=0\nchoice generators:  thread=888 (signal=0,lock=16,sharedRef=656,threadApi=37,reschedule=142), data=0\nheap:               new=3348,released=3933,maxLive=542,gcCycles=1459\ninstructions:       36196\nmax memory:         981MB\nloaded code:        classes=102,methods=1946\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 46.23%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 43.56%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=3069,visited=2365,backtracked=5434,end=551\nsearch:             maxDepth=43,constraints=0\nchoice generators:  thread=3064 (signal=0,lock=66,sharedRef=2211,threadApi=76,reschedule=569), data=0\nheap:               new=8551,released=15668,maxLive=540,gcCycles=5035\ninstructions:       99368\nmax memory:         981MB\nloaded code:        classes=102,methods=1946\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 46.80%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.27%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=882,visited=697,backtracked=1579,end=137\nsearch:             maxDepth=44,constraints=0\nchoice generators:  thread=877 (signal=0,lock=16,sharedRef=647,threadApi=36,reschedule=141), data=0\nheap:               new=3232,released=3907,maxLive=542,gcCycles=1439\ninstructions:       35631\nmax memory:         981MB\nloaded code:        classes=102,methods=1946\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            61.85,
            66.34,
            61.85
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Vision {\n    String getData();\n}\n\nclass VisionCastException extends Exception {\n    public VisionCastException(String message) {\n        super(message);\n    }\n    \n    public VisionCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass DreamWeaver {\n    private FutureTask<Vision> futureTask;\n    private Thread workerThread;\n    \n    public DreamWeaver() {\n        Callable<Vision> callable = new Callable<Vision>() {\n            @Override\n            public Vision call() throws Exception {\n                return loadVision();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n        this.workerThread = new Thread(futureTask);\n    }\n    \n    private Vision loadVision() throws VisionCastException {\n        try {\n            Thread.sleep(1000);\n            if (Math.random() > 0.5) {\n                throw new VisionCastException(\"Failed to manifest vision\");\n            }\n            return new Vision() {\n                @Override\n                public String getData() {\n                    return \"Mystical Vision Manifested\";\n                }\n            };\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread.start();\n    }\n    \n    public Vision get() throws VisionCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision retrieval interrupted\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof VisionCastException) {\n                throw (VisionCastException) cause;\n            } else {\n                throw new VisionCastException(\"Unexpected error during vision summoning\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        DreamWeaver dreamWeaver = new DreamWeaver();\n        \n        System.out.println(\"Starting vision summoning...\");\n        dreamWeaver.start();\n        \n        System.out.println(\"Doing other work while vision is being summoned...\");\n        \n        try {\n            Thread.sleep(500);\n            System.out.println(\"Still working...\");\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        try {\n            System.out.println(\"Attempting to capture the vision...\");\n            Vision vision = dreamWeaver.get();\n            System.out.println(\"Vision captured: \" + vision.getData());\n        } catch (VisionCastException e) {\n            System.out.println(\"Failed to capture vision: \" + e.getMessage());\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Vision {\n    String getData();\n}\n\nclass VisionCastException extends Exception {\n    public VisionCastException(String message) {\n        super(message);\n    }\n    \n    public VisionCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConcreteVision implements Vision {\n    private final String data;\n    \n    public ConcreteVision(String data) {\n        this.data = data;\n    }\n    \n    public String getData() {\n        return data;\n    }\n}\n\nclass DreamWeaver {\n    private FutureTask<Vision> futureTask;\n    private Thread workerThread;\n    \n    public DreamWeaver() {\n        Callable<Vision> callable = new Callable<Vision>() {\n            @Override\n            public Vision call() throws Exception {\n                return loadVision();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n        this.workerThread = new Thread(futureTask);\n    }\n    \n    private Vision loadVision() throws VisionCastException {\n        try {\n            Thread.sleep(1000);\n            if (Math.random() < 0.3) {\n                throw new VisionCastException(\"Vision manifestation failed\");\n            }\n            return new ConcreteVision(\"Mystical vision data: \" + System.currentTimeMillis());\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread.start();\n    }\n    \n    public Vision get() throws VisionCastException {\n        try {\n            return futureTask.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof VisionCastException) {\n                throw (VisionCastException) cause;\n            } else {\n                throw new VisionCastException(\"Unexpected error during vision summoning\", cause);\n            }\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision retrieval interrupted\", e);\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        DreamWeaver dreamWeaver = new DreamWeaver();\n        \n        System.out.println(\"Starting vision summoning...\");\n        dreamWeaver.start();\n        \n        System.out.println(\"Doing other work while vision is being summoned...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Now retrieving the vision...\");\n        try {\n            Vision vision = dreamWeaver.get();\n            System.out.println(\"Vision received: \" + vision.getData());\n        } catch (VisionCastException e) {\n            System.err.println(\"Failed to retrieve vision: \" + e.getMessage());\n            if (e.getCause() != null) {\n                System.err.println(\"Cause: \" + e.getCause().getMessage());\n            }\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Vision {\n    String getData();\n}\n\nclass VisionCastException extends Exception {\n    public VisionCastException(String message) {\n        super(message);\n    }\n    \n    public VisionCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass DreamWeaver {\n    private FutureTask<Vision> futureTask;\n    private Thread workerThread;\n    \n    public DreamWeaver() {\n        Callable<Vision> callable = new Callable<Vision>() {\n            @Override\n            public Vision call() throws Exception {\n                return loadVision();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n        this.workerThread = new Thread(futureTask);\n    }\n    \n    private Vision loadVision() throws VisionCastException {\n        try {\n            Thread.sleep(1000);\n            if (Math.random() < 0.3) {\n                throw new VisionCastException(\"Failed to manifest vision\");\n            }\n            return new Vision() {\n                @Override\n                public String getData() {\n                    return \"Mystical Vision Manifested\";\n                }\n            };\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread.start();\n    }\n    \n    public Vision get() throws VisionCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            throw new VisionCastException(\"Vision retrieval interrupted\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof VisionCastException) {\n                throw (VisionCastException) cause;\n            } else {\n                throw new VisionCastException(\"Unexpected error during vision summoning\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        DreamWeaver dreamWeaver = new DreamWeaver();\n        \n        System.out.println(\"Starting vision summoning...\");\n        dreamWeaver.start();\n        \n        System.out.println(\"Doing other work while vision is being summoned...\");\n        \n        try {\n            Thread.sleep(500);\n            System.out.println(\"Still working...\");\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        try {\n            System.out.println(\"Attempting to capture the vision...\");\n            Vision vision = dreamWeaver.get();\n            System.out.println(\"Vision captured: \" + vision.getData());\n        } catch (VisionCastException e) {\n            System.err.println(\"Failed to capture vision: \" + e.getMessage());\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using FutureTask to preload data that is needed later. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class called PhantomLoader that simulates the conjuring of relics using a separate thread. The class should use a FutureTask to invoke the relic creation asynchronously and provide two main operations: a method to activate the background task and another to harvest the result of the task when needed. The class should include: \n\nA method Relic loadRelic() which performs relic summoning and may throw a custom exception called RelicCastException. \nA FutureTask that wraps a Callable to execute the loadRelic method in the background. A dedicated Thread instance to guide the FutureTask. \nA start() method to trigger the execution of the background task. \nA get() method that returns the conjured Relic and propagates any exceptions thrown during the summoning, including properly handling and rethrowing them (e.g., encapsulating unexpected exceptions in a utility-like manner). \nAlso define: \nAn interface Relic as a placeholder for the summoned data type. \nA custom exception class RelicCastException that extends Exception. Ensure the code is structured to be non-blocking during relic summoning but pauses only when retrieving the result via get(), and correctly handles error propagation from the background task. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\npublic class PhantomLoader {\n    private FutureTask<Relic> futureTask;\n    private Thread workerThread;\n    \n    public PhantomLoader() {\n        Callable<Relic> callable = new Callable<Relic>() {\n            @Override\n            public Relic call() throws Exception {\n                return loadRelic();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n        this.workerThread = new Thread(futureTask);\n    }\n    \n    private Relic loadRelic() throws RelicCastException {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Relic summoning interrupted\");\n        }\n        \n        if (Math.random() < 0.3) {\n            throw new RelicCastException(\"Failed to summon relic\");\n        }\n        \n        return new Relic() {\n            @Override\n            public String getName() {\n                return \"Ancient Relic\";\n            }\n        };\n    }\n    \n    public void start() {\n        workerThread.start();\n    }\n    \n    public Relic get() throws RelicCastException {\n        try {\n            return futureTask.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof RelicCastException) {\n                throw (RelicCastException) cause;\n            } else {\n                throw new RelicCastException(\"Unexpected error during relic summoning: \" + cause.getMessage());\n            }\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Relic retrieval interrupted\");\n        }\n    }\n    \n    public static void main(String[] args) {\n        PhantomLoader loader = new PhantomLoader();\n        \n        System.out.println(\"Starting relic summoning...\");\n        loader.start();\n        \n        System.out.println(\"Doing other work while relic is being summoned...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Attempting to harvest the relic...\");\n        try {\n            Relic relic = loader.get();\n            System.out.println(\"Successfully summoned: \" + relic.getName());\n        } catch (RelicCastException e) {\n            System.out.println(\"Failed to summon relic: \" + e.getMessage());\n        }\n    }\n}\n\ninterface Relic {\n    String getName();\n}\n\nclass RelicCastException extends Exception {\n    public RelicCastException(String message) {\n        super(message);\n    }\n}",
            "import java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\nimport java.util.Random;\n\ninterface Relic {\n    String getName();\n}\n\nclass RelicCastException extends Exception {\n    public RelicCastException(String message) {\n        super(message);\n    }\n    \n    public RelicCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass AncientRelic implements Relic {\n    private final String name;\n    \n    public AncientRelic(String name) {\n        this.name = name;\n    }\n    \n    public String getName() {\n        return name;\n    }\n}\n\nclass PhantomLoader {\n    private FutureTask<Relic> futureTask;\n    private Thread workerThread;\n    \n    public PhantomLoader() {\n        Callable<Relic> callable = new Callable<Relic>() {\n            public Relic call() throws RelicCastException {\n                return loadRelic();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Relic loadRelic() throws RelicCastException {\n        try {\n            Thread.sleep(1000);\n            Random random = new Random();\n            if (random.nextBoolean()) {\n                throw new RelicCastException(\"Failed to summon relic\");\n            }\n            return new AncientRelic(\"Sacred Artifact \" + random.nextInt(1000));\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Relic summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Relic get() throws RelicCastException {\n        try {\n            return futureTask.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof RelicCastException) {\n                throw (RelicCastException) cause;\n            }\n            throw new RelicCastException(\"Unexpected error during relic summoning\", cause);\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Interrupted while waiting for relic\", e);\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        PhantomLoader loader = new PhantomLoader();\n        \n        System.out.println(\"Starting relic summoning...\");\n        loader.start();\n        \n        System.out.println(\"Doing other work while relic is being summoned...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Attempting to harvest the relic...\");\n        try {\n            Relic relic = loader.get();\n            System.out.println(\"Successfully summoned: \" + relic.getName());\n        } catch (RelicCastException e) {\n            System.out.println(\"Failed to summon relic: \" + e.getMessage());\n        }\n    }\n}",
            "import java.util.concurrent.Callable;\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.ExecutionException;\n\ninterface Relic {\n    String getName();\n}\n\nclass RelicCastException extends Exception {\n    public RelicCastException(String message) {\n        super(message);\n    }\n    \n    public RelicCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConcreteRelic implements Relic {\n    private final String name;\n    \n    public ConcreteRelic(String name) {\n        this.name = name;\n    }\n    \n    public String getName() {\n        return name;\n    }\n}\n\nclass PhantomLoader {\n    private FutureTask<Relic> futureTask;\n    private Thread workerThread;\n    \n    public PhantomLoader() {\n        Callable<Relic> callable = new Callable<Relic>() {\n            public Relic call() throws RelicCastException {\n                return loadRelic();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Relic loadRelic() throws RelicCastException {\n        try {\n            Thread.sleep(1000);\n            if (Math.random() > 0.5) {\n                throw new RelicCastException(\"Failed to summon relic\");\n            }\n            return new ConcreteRelic(\"Ancient Artifact\");\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Relic get() throws RelicCastException {\n        try {\n            return futureTask.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof RelicCastException) {\n                throw (RelicCastException) cause;\n            } else {\n                throw new RelicCastException(\"Unexpected error during relic summoning\", cause);\n            }\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Retrieval interrupted\", e);\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        PhantomLoader loader = new PhantomLoader();\n        System.out.println(\"Starting relic summoning...\");\n        loader.start();\n        \n        System.out.println(\"Doing other work while relic is being summoned...\");\n        \n        try {\n            Thread.sleep(500);\n            System.out.println(\"Still working...\");\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        try {\n            System.out.println(\"Attempting to harvest the relic...\");\n            Relic relic = loader.get();\n            System.out.println(\"Successfully conjured: \" + relic.getName());\n        } catch (RelicCastException e) {\n            System.out.println(\"Failed to conjure relic: \" + e.getMessage());\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.*;\n\n/**\n* Preloader\n*\n* Using FutureTask to preload data that is needed later\n*\n* @author Brian Goetz and Tim Peierls\n*/\npublic class Preloader {\n// Simulate product information loading\nProductInfo loadProductInfo() throws DataLoadException {\ntry {\nThread.sleep(2000); // Simulate loading delay\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\nthrow new DataLoadException();\n}\nreturn new ProductInfoImpl(\"Awesome Product\", 99.99);\n}\n\nprivate final FutureTask<ProductInfo> future =\nnew FutureTask<>(new Callable<ProductInfo>() {\npublic ProductInfo call() throws DataLoadException {\nreturn loadProductInfo();\n}\n});\nprivate final Thread thread = new Thread(future);\n\npublic void start() {\nthread.start();\n}\n\npublic ProductInfo get() throws DataLoadException, InterruptedException {\ntry {\nreturn future.get();\n} catch (ExecutionException e) {\nThrowable cause = e.getCause();\nif (cause instanceof DataLoadException)\nthrow (DataLoadException) cause;\nelse\nthrow LaunderThrowable.launderThrowable(cause);\n}\n}\n\ninterface ProductInfo {\nString getName();\ndouble getPrice();\n}\n\nstatic class ProductInfoImpl implements ProductInfo {\nprivate final String name;\nprivate final double price;\n\npublic ProductInfoImpl(String name, double price) {\nthis.name = name;\nthis.price = price;\n}\n\npublic String getName() {\nreturn name;\n}\n\npublic double getPrice() {\nreturn price;\n}\n\n@Override\npublic String toString() {\nreturn \"ProductInfo{name='\" + name + \"', price=\" + price + \"}\";\n}\n}\n\n// Utility class: for throwing unchecked exceptions\nstatic class LaunderThrowable {\nstatic RuntimeException launderThrowable(Throwable t) {\nif (t instanceof RuntimeException)\nreturn (RuntimeException) t;\nelse if (t instanceof Error)\nthrow (Error) t;\nelse\nthrow new IllegalStateException(\"Not unchecked\", t);\n}\n}\n\n// Main entry point\npublic static void main(String[] args) {\nSystem.out.println(\"Starting preloader...\");\nPreloader preloader = new Preloader();\npreloader.start();\n\ntry {\nSystem.out.println(\"Doing something else in the main thread...\");\nThread.sleep(1000);\n\nSystem.out.println(\"Waiting for product info...\");\nProductInfo productInfo = preloader.get();\nSystem.out.println(\"Loaded product: \" + productInfo);\n} catch (DataLoadException | InterruptedException e) {\ne.printStackTrace();\n}\n}\n}\n\nclass DataLoadException extends Exception {\npublic DataLoadException() {\nsuper(\"Failed to load product data.\");\n}\n}",
        "max_depth": "36",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 46.81%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.31%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=893,visited=707,backtracked=1600,end=138\nsearch:             maxDepth=44,constraints=0\nchoice generators:  thread=888 (signal=0,lock=16,sharedRef=656,threadApi=37,reschedule=142), data=0\nheap:               new=3222,released=3940,maxLive=537,gcCycles=1459\ninstructions:       35933\nmax memory:         981MB\nloaded code:        classes=100,methods=1942\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 47.19%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.44%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=504,visited=405,backtracked=909,end=72\nsearch:             maxDepth=37,constraints=0\nchoice generators:  thread=502 (signal=0,lock=9,sharedRef=373,threadApi=24,reschedule=74), data=0\nheap:               new=2466,released=2257,maxLive=543,gcCycles=834\ninstructions:       25867\nmax memory:         981MB\nloaded code:        classes=101,methods=1955\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 46.81%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.31%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=893,visited=707,backtracked=1600,end=138\nsearch:             maxDepth=42,constraints=0\nchoice generators:  thread=888 (signal=0,lock=16,sharedRef=656,threadApi=37,reschedule=142), data=0\nheap:               new=3242,released=3933,maxLive=542,gcCycles=1459\ninstructions:       36315\nmax memory:         981MB\nloaded code:        classes=102,methods=1946\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            60.86,
            64.43,
            63.66
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\npublic class PhantomLoader {\n    private FutureTask<Relic> futureTask;\n    private Thread workerThread;\n    \n    public PhantomLoader() {\n        Callable<Relic> callable = new Callable<Relic>() {\n            @Override\n            public Relic call() throws Exception {\n                return loadRelic();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n        this.workerThread = new Thread(futureTask);\n    }\n    \n    private Relic loadRelic() throws RelicCastException {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Relic summoning interrupted\");\n        }\n        \n        if (Math.random() < 0.3) {\n            throw new RelicCastException(\"Failed to summon relic\");\n        }\n        \n        return new Relic() {\n            @Override\n            public String getName() {\n                return \"Ancient Relic\";\n            }\n        };\n    }\n    \n    public void start() {\n        workerThread.start();\n    }\n    \n    public Relic get() throws RelicCastException {\n        try {\n            return futureTask.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof RelicCastException) {\n                throw (RelicCastException) cause;\n            } else {\n                throw new RelicCastException(\"Unexpected error during relic summoning: \" + cause.getMessage());\n            }\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Relic retrieval interrupted\");\n        }\n    }\n    \n    public static void main(String[] args) {\n        PhantomLoader loader = new PhantomLoader();\n        \n        System.out.println(\"Starting relic summoning...\");\n        loader.start();\n        \n        System.out.println(\"Doing other work while relic is being summoned...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Attempting to harvest the relic...\");\n        try {\n            Relic relic = loader.get();\n            System.out.println(\"Successfully summoned: \" + relic.getName());\n        } catch (RelicCastException e) {\n            System.out.println(\"Failed to summon relic: \" + e.getMessage());\n        }\n    }\n}\n\ninterface Relic {\n    String getName();\n}\n\nclass RelicCastException extends Exception {\n    public RelicCastException(String message) {\n        super(message);\n    }\n}\n```",
            "```java\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\nimport java.util.Random;\n\ninterface Relic {\n    String getName();\n}\n\nclass RelicCastException extends Exception {\n    public RelicCastException(String message) {\n        super(message);\n    }\n    \n    public RelicCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass AncientRelic implements Relic {\n    private final String name;\n    \n    public AncientRelic(String name) {\n        this.name = name;\n    }\n    \n    public String getName() {\n        return name;\n    }\n}\n\nclass PhantomLoader {\n    private FutureTask<Relic> futureTask;\n    private Thread workerThread;\n    \n    public PhantomLoader() {\n        Callable<Relic> callable = new Callable<Relic>() {\n            public Relic call() throws RelicCastException {\n                return loadRelic();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Relic loadRelic() throws RelicCastException {\n        try {\n            Thread.sleep(1000);\n            Random random = new Random();\n            if (random.nextBoolean()) {\n                throw new RelicCastException(\"Failed to summon relic\");\n            }\n            return new AncientRelic(\"Sacred Artifact \" + random.nextInt(1000));\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Relic summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Relic get() throws RelicCastException {\n        try {\n            return futureTask.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof RelicCastException) {\n                throw (RelicCastException) cause;\n            }\n            throw new RelicCastException(\"Unexpected error during relic summoning\", cause);\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Interrupted while waiting for relic\", e);\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        PhantomLoader loader = new PhantomLoader();\n        \n        System.out.println(\"Starting relic summoning...\");\n        loader.start();\n        \n        System.out.println(\"Doing other work while relic is being summoned...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Attempting to harvest the relic...\");\n        try {\n            Relic relic = loader.get();\n            System.out.println(\"Successfully summoned: \" + relic.getName());\n        } catch (RelicCastException e) {\n            System.out.println(\"Failed to summon relic: \" + e.getMessage());\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.ExecutionException;\n\ninterface Relic {\n    String getName();\n}\n\nclass RelicCastException extends Exception {\n    public RelicCastException(String message) {\n        super(message);\n    }\n    \n    public RelicCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConcreteRelic implements Relic {\n    private final String name;\n    \n    public ConcreteRelic(String name) {\n        this.name = name;\n    }\n    \n    public String getName() {\n        return name;\n    }\n}\n\nclass PhantomLoader {\n    private FutureTask<Relic> futureTask;\n    private Thread workerThread;\n    \n    public PhantomLoader() {\n        Callable<Relic> callable = new Callable<Relic>() {\n            public Relic call() throws RelicCastException {\n                return loadRelic();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Relic loadRelic() throws RelicCastException {\n        try {\n            Thread.sleep(1000);\n            if (Math.random() > 0.5) {\n                throw new RelicCastException(\"Failed to summon relic\");\n            }\n            return new ConcreteRelic(\"Ancient Artifact\");\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Summoning interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Relic get() throws RelicCastException {\n        try {\n            return futureTask.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof RelicCastException) {\n                throw (RelicCastException) cause;\n            } else {\n                throw new RelicCastException(\"Unexpected error during relic summoning\", cause);\n            }\n        } catch (InterruptedException e) {\n            throw new RelicCastException(\"Retrieval interrupted\", e);\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        PhantomLoader loader = new PhantomLoader();\n        System.out.println(\"Starting relic summoning...\");\n        loader.start();\n        \n        System.out.println(\"Doing other work while relic is being summoned...\");\n        \n        try {\n            Thread.sleep(500);\n            System.out.println(\"Still working...\");\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        try {\n            System.out.println(\"Attempting to harvest the relic...\");\n            Relic relic = loader.get();\n            System.out.println(\"Successfully conjured: \" + relic.getName());\n        } catch (RelicCastException e) {\n            System.out.println(\"Failed to conjure relic: \" + e.getMessage());\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using FutureTask to preload data that is needed later. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class called StarForge that simulates the crafting of constellations using a separate thread. The class should use a FutureTask to weave the constellations asynchronously and provide two main operations: a method to ignite the background task and another to collect the result of the task when needed. The class should include: \n\nA method Constellation loadConstellation() which performs constellation weaving and may throw a custom exception called ConstellationCastException. \nA FutureTask that encloses a Callable to invoke the loadConstellation method in the background. A dedicated Thread instance to navigate the FutureTask. \nA start() method to begin the execution of the background task. \nA get() method that retrieves the crafted Constellation and propagates any exceptions thrown during the weaving process, including properly handling and rethrowing them (e.g., encasing unexpected exceptions in a utility-like manner). \nAlso define: \nAn interface Constellation as a placeholder for the crafted data type. \nA custom exception class ConstellationCastException that extends Exception. Ensure the code is structured to be non-blocking during constellation weaving but pauses only when retrieving the result via get(), and correctly handles error propagation from the background task. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Constellation {\n    String getName();\n}\n\nclass ConstellationCastException extends Exception {\n    public ConstellationCastException(String message) {\n        super(message);\n    }\n    \n    public ConstellationCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConstellationImpl implements Constellation {\n    private final String name;\n    \n    public ConstellationImpl(String name) {\n        this.name = name;\n    }\n    \n    public String getName() {\n        return name;\n    }\n}\n\nclass StarForge {\n    private FutureTask<Constellation> futureTask;\n    private Thread workerThread;\n    \n    public StarForge() {\n        Callable<Constellation> callable = new Callable<Constellation>() {\n            public Constellation call() throws ConstellationCastException {\n                return loadConstellation();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Constellation loadConstellation() throws ConstellationCastException {\n        try {\n            Thread.sleep(2000);\n            if (Math.random() > 0.7) {\n                throw new ConstellationCastException(\"Failed to weave constellation\");\n            }\n            return new ConstellationImpl(\"Orion\");\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new ConstellationCastException(\"Constellation weaving interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Constellation get() throws ConstellationCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new ConstellationCastException(\"Interrupted while waiting for constellation\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof ConstellationCastException) {\n                throw (ConstellationCastException) cause;\n            } else {\n                throw new ConstellationCastException(\"Unexpected error during constellation weaving\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        StarForge forge = new StarForge();\n        \n        System.out.println(\"Starting constellation weaving...\");\n        forge.start();\n        \n        System.out.println(\"Doing other work while constellation is being crafted...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        try {\n            System.out.println(\"Retrieving constellation...\");\n            Constellation constellation = forge.get();\n            System.out.println(\"Successfully crafted constellation: \" + constellation.getName());\n        } catch (ConstellationCastException e) {\n            System.err.println(\"Failed to craft constellation: \" + e.getMessage());\n        }\n    }\n}",
            "import java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Constellation {\n}\n\nclass ConstellationCastException extends Exception {\n    public ConstellationCastException(String message) {\n        super(message);\n    }\n    \n    public ConstellationCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConstellationImpl implements Constellation {\n    private final String name;\n    \n    public ConstellationImpl(String name) {\n        this.name = name;\n    }\n    \n    public String toString() {\n        return \"Constellation: \" + name;\n    }\n}\n\nclass StarForge {\n    private FutureTask<Constellation> futureTask;\n    private Thread workerThread;\n    \n    public StarForge() {\n        Callable<Constellation> callable = new Callable<Constellation>() {\n            public Constellation call() throws ConstellationCastException {\n                return loadConstellation();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Constellation loadConstellation() throws ConstellationCastException {\n        try {\n            Thread.sleep(2000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new ConstellationCastException(\"Constellation weaving interrupted\", e);\n        }\n        \n        if (Math.random() > 0.7) {\n            throw new ConstellationCastException(\"Failed to weave constellation\");\n        }\n        \n        return new ConstellationImpl(\"Orion\");\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Constellation get() throws ConstellationCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new ConstellationCastException(\"Interrupted while waiting for constellation\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof ConstellationCastException) {\n                throw (ConstellationCastException) cause;\n            } else {\n                throw new ConstellationCastException(\"Unexpected error during constellation weaving\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        StarForge forge = new StarForge();\n        \n        System.out.println(\"Starting constellation weaving...\");\n        forge.start();\n        \n        System.out.println(\"Doing other work while constellation is being woven...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Now waiting for constellation to complete...\");\n        try {\n            Constellation constellation = forge.get();\n            System.out.println(\"Successfully crafted: \" + constellation);\n        } catch (ConstellationCastException e) {\n            System.err.println(\"Failed to craft constellation: \" + e.getMessage());\n        }\n    }\n}",
            "import java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Constellation {\n}\n\nclass ConstellationCastException extends Exception {\n    public ConstellationCastException(String message) {\n        super(message);\n    }\n    \n    public ConstellationCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConstellationImpl implements Constellation {\n    private final String name;\n    \n    public ConstellationImpl(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Constellation: \" + name;\n    }\n}\n\nclass StarForge {\n    private FutureTask<Constellation> futureTask;\n    private Thread workerThread;\n    \n    public StarForge() {\n        Callable<Constellation> callable = new Callable<Constellation>() {\n            @Override\n            public Constellation call() throws ConstellationCastException {\n                return loadConstellation();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Constellation loadConstellation() throws ConstellationCastException {\n        try {\n            Thread.sleep(2000);\n            if (Math.random() > 0.7) {\n                throw new ConstellationCastException(\"Failed to weave constellation\");\n            }\n            return new ConstellationImpl(\"Orion\");\n        } catch (InterruptedException e) {\n            throw new ConstellationCastException(\"Constellation weaving interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Constellation get() throws ConstellationCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            throw new ConstellationCastException(\"Interrupted while waiting for constellation\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof ConstellationCastException) {\n                throw (ConstellationCastException) cause;\n            } else {\n                throw new ConstellationCastException(\"Unexpected error during constellation weaving\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        StarForge forge = new StarForge();\n        \n        System.out.println(\"Starting constellation weaving...\");\n        forge.start();\n        \n        System.out.println(\"Doing other work while constellation is being woven...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        try {\n            System.out.println(\"Retrieving constellation...\");\n            Constellation constellation = forge.get();\n            System.out.println(\"Successfully crafted: \" + constellation);\n        } catch (ConstellationCastException e) {\n            System.err.println(\"Failed to craft constellation: \" + e.getMessage());\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.*;\n\n/**\n* Preloader\n*\n* Using FutureTask to preload data that is needed later\n*\n* @author Brian Goetz and Tim Peierls\n*/\npublic class Preloader {\n// Simulate product information loading\nProductInfo loadProductInfo() throws DataLoadException {\ntry {\nThread.sleep(2000); // Simulate loading delay\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\nthrow new DataLoadException();\n}\nreturn new ProductInfoImpl(\"Awesome Product\", 99.99);\n}\n\nprivate final FutureTask<ProductInfo> future =\nnew FutureTask<>(new Callable<ProductInfo>() {\npublic ProductInfo call() throws DataLoadException {\nreturn loadProductInfo();\n}\n});\nprivate final Thread thread = new Thread(future);\n\npublic void start() {\nthread.start();\n}\n\npublic ProductInfo get() throws DataLoadException, InterruptedException {\ntry {\nreturn future.get();\n} catch (ExecutionException e) {\nThrowable cause = e.getCause();\nif (cause instanceof DataLoadException)\nthrow (DataLoadException) cause;\nelse\nthrow LaunderThrowable.launderThrowable(cause);\n}\n}\n\ninterface ProductInfo {\nString getName();\ndouble getPrice();\n}\n\nstatic class ProductInfoImpl implements ProductInfo {\nprivate final String name;\nprivate final double price;\n\npublic ProductInfoImpl(String name, double price) {\nthis.name = name;\nthis.price = price;\n}\n\npublic String getName() {\nreturn name;\n}\n\npublic double getPrice() {\nreturn price;\n}\n\n@Override\npublic String toString() {\nreturn \"ProductInfo{name='\" + name + \"', price=\" + price + \"}\";\n}\n}\n\n// Utility class: for throwing unchecked exceptions\nstatic class LaunderThrowable {\nstatic RuntimeException launderThrowable(Throwable t) {\nif (t instanceof RuntimeException)\nreturn (RuntimeException) t;\nelse if (t instanceof Error)\nthrow (Error) t;\nelse\nthrow new IllegalStateException(\"Not unchecked\", t);\n}\n}\n\n// Main entry point\npublic static void main(String[] args) {\nSystem.out.println(\"Starting preloader...\");\nPreloader preloader = new Preloader();\npreloader.start();\n\ntry {\nSystem.out.println(\"Doing something else in the main thread...\");\nThread.sleep(1000);\n\nSystem.out.println(\"Waiting for product info...\");\nProductInfo productInfo = preloader.get();\nSystem.out.println(\"Loaded product: \" + productInfo);\n} catch (DataLoadException | InterruptedException e) {\ne.printStackTrace();\n}\n}\n}\n\nclass DataLoadException extends Exception {\npublic DataLoadException() {\nsuper(\"Failed to load product data.\");\n}\n}",
        "max_depth": "36",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 47.36%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 43.85%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=639,visited=499,backtracked=1138,end=96\nsearch:             maxDepth=41,constraints=0\nchoice generators:  thread=636 (signal=0,lock=10,sharedRef=465,threadApi=24,reschedule=100), data=0\nheap:               new=2368,released=2710,maxLive=540,gcCycles=1062\ninstructions:       27518\nmax memory:         981MB\nloaded code:        classes=102,methods=1946\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 46.80%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.27%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=882,visited=697,backtracked=1579,end=137\nsearch:             maxDepth=44,constraints=0\nchoice generators:  thread=877 (signal=0,lock=16,sharedRef=647,threadApi=36,reschedule=141), data=0\nheap:               new=3600,released=4267,maxLive=540,gcCycles=1439\ninstructions:       37401\nmax memory:         981MB\nloaded code:        classes=102,methods=1945\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 46.80%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.27%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=882,visited=697,backtracked=1579,end=137\nsearch:             maxDepth=41,constraints=0\nchoice generators:  thread=877 (signal=0,lock=16,sharedRef=647,threadApi=36,reschedule=141), data=0\nheap:               new=3624,released=4260,maxLive=540,gcCycles=1439\ninstructions:       37481\nmax memory:         981MB\nloaded code:        classes=102,methods=1945\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            64.43,
            63.1,
            63.44
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Constellation {\n    String getName();\n}\n\nclass ConstellationCastException extends Exception {\n    public ConstellationCastException(String message) {\n        super(message);\n    }\n    \n    public ConstellationCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConstellationImpl implements Constellation {\n    private final String name;\n    \n    public ConstellationImpl(String name) {\n        this.name = name;\n    }\n    \n    public String getName() {\n        return name;\n    }\n}\n\nclass StarForge {\n    private FutureTask<Constellation> futureTask;\n    private Thread workerThread;\n    \n    public StarForge() {\n        Callable<Constellation> callable = new Callable<Constellation>() {\n            public Constellation call() throws ConstellationCastException {\n                return loadConstellation();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Constellation loadConstellation() throws ConstellationCastException {\n        try {\n            Thread.sleep(2000);\n            if (Math.random() > 0.7) {\n                throw new ConstellationCastException(\"Failed to weave constellation\");\n            }\n            return new ConstellationImpl(\"Orion\");\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new ConstellationCastException(\"Constellation weaving interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Constellation get() throws ConstellationCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new ConstellationCastException(\"Interrupted while waiting for constellation\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof ConstellationCastException) {\n                throw (ConstellationCastException) cause;\n            } else {\n                throw new ConstellationCastException(\"Unexpected error during constellation weaving\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        StarForge forge = new StarForge();\n        \n        System.out.println(\"Starting constellation weaving...\");\n        forge.start();\n        \n        System.out.println(\"Doing other work while constellation is being crafted...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        try {\n            System.out.println(\"Retrieving constellation...\");\n            Constellation constellation = forge.get();\n            System.out.println(\"Successfully crafted constellation: \" + constellation.getName());\n        } catch (ConstellationCastException e) {\n            System.err.println(\"Failed to craft constellation: \" + e.getMessage());\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Constellation {\n}\n\nclass ConstellationCastException extends Exception {\n    public ConstellationCastException(String message) {\n        super(message);\n    }\n    \n    public ConstellationCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConstellationImpl implements Constellation {\n    private final String name;\n    \n    public ConstellationImpl(String name) {\n        this.name = name;\n    }\n    \n    public String toString() {\n        return \"Constellation: \" + name;\n    }\n}\n\nclass StarForge {\n    private FutureTask<Constellation> futureTask;\n    private Thread workerThread;\n    \n    public StarForge() {\n        Callable<Constellation> callable = new Callable<Constellation>() {\n            public Constellation call() throws ConstellationCastException {\n                return loadConstellation();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Constellation loadConstellation() throws ConstellationCastException {\n        try {\n            Thread.sleep(2000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new ConstellationCastException(\"Constellation weaving interrupted\", e);\n        }\n        \n        if (Math.random() > 0.7) {\n            throw new ConstellationCastException(\"Failed to weave constellation\");\n        }\n        \n        return new ConstellationImpl(\"Orion\");\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Constellation get() throws ConstellationCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new ConstellationCastException(\"Interrupted while waiting for constellation\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof ConstellationCastException) {\n                throw (ConstellationCastException) cause;\n            } else {\n                throw new ConstellationCastException(\"Unexpected error during constellation weaving\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        StarForge forge = new StarForge();\n        \n        System.out.println(\"Starting constellation weaving...\");\n        forge.start();\n        \n        System.out.println(\"Doing other work while constellation is being woven...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Now waiting for constellation to complete...\");\n        try {\n            Constellation constellation = forge.get();\n            System.out.println(\"Successfully crafted: \" + constellation);\n        } catch (ConstellationCastException e) {\n            System.err.println(\"Failed to craft constellation: \" + e.getMessage());\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\n\ninterface Constellation {\n}\n\nclass ConstellationCastException extends Exception {\n    public ConstellationCastException(String message) {\n        super(message);\n    }\n    \n    public ConstellationCastException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ConstellationImpl implements Constellation {\n    private final String name;\n    \n    public ConstellationImpl(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Constellation: \" + name;\n    }\n}\n\nclass StarForge {\n    private FutureTask<Constellation> futureTask;\n    private Thread workerThread;\n    \n    public StarForge() {\n        Callable<Constellation> callable = new Callable<Constellation>() {\n            @Override\n            public Constellation call() throws ConstellationCastException {\n                return loadConstellation();\n            }\n        };\n        this.futureTask = new FutureTask<>(callable);\n    }\n    \n    private Constellation loadConstellation() throws ConstellationCastException {\n        try {\n            Thread.sleep(2000);\n            if (Math.random() > 0.7) {\n                throw new ConstellationCastException(\"Failed to weave constellation\");\n            }\n            return new ConstellationImpl(\"Orion\");\n        } catch (InterruptedException e) {\n            throw new ConstellationCastException(\"Constellation weaving interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        workerThread = new Thread(futureTask);\n        workerThread.start();\n    }\n    \n    public Constellation get() throws ConstellationCastException {\n        try {\n            return futureTask.get();\n        } catch (InterruptedException e) {\n            throw new ConstellationCastException(\"Interrupted while waiting for constellation\", e);\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof ConstellationCastException) {\n                throw (ConstellationCastException) cause;\n            } else {\n                throw new ConstellationCastException(\"Unexpected error during constellation weaving\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        StarForge forge = new StarForge();\n        \n        System.out.println(\"Starting constellation weaving...\");\n        forge.start();\n        \n        System.out.println(\"Doing other work while constellation is being woven...\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        try {\n            System.out.println(\"Retrieving constellation...\");\n            Constellation constellation = forge.get();\n            System.out.println(\"Successfully crafted: \" + constellation);\n        } catch (ConstellationCastException e) {\n            System.err.println(\"Failed to craft constellation: \" + e.getMessage());\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Waiting for results to be calculated in parallel. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write Java code that transforms linear enchantment into simultaneous conjuration using an Executor. The code should include two main processing methods: one that weaves a list of talismans sequentially by iterating and enchanting each talisman in turn, and another that dispatches each talisman for parallel enchantment via an executor. Additionally, implement recursive versions of both sequential and parallel processing methods that traverse a grove structure of sigils, calculating results and collecting them in a thread-safe manner. The parallel version should properly leverage an ExecutorService to execute tasks concurrently, ensure all tasks complete before returning the final result collection, and use appropriate concurrency utilities for thread safety. Define interfaces Talisman and SigilNode, where SigilNode supports computation and retrieval of child sigils. Ensure the design follows good abstraction principles and includes proper generic typing. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\ninterface Talisman {\n    String enchant();\n}\n\ninterface SigilNode {\n    int compute();\n    List<SigilNode> getChildren();\n}\n\nclass SimpleTalisman implements Talisman {\n    private final String name;\n    \n    public SimpleTalisman(String name) {\n        this.name = name;\n    }\n    \n    public String enchant() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return \"Enchanted-\" + name;\n    }\n}\n\nclass SimpleSigilNode implements SigilNode {\n    private final int value;\n    private final List<SigilNode> children;\n    \n    public SimpleSigilNode(int value, List<SigilNode> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    public int compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value * 2;\n    }\n    \n    public List<SigilNode> getChildren() {\n        return new ArrayList<>(children);\n    }\n}\n\nclass EnchantmentProcessor {\n    private final ExecutorService executor;\n    \n    public EnchantmentProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public List<String> weaveSequential(List<Talisman> talismans) {\n        List<String> results = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            results.add(talisman.enchant());\n        }\n        return results;\n    }\n    \n    public List<String> weaveParallel(List<Talisman> talismans) {\n        List<Future<String>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(talisman::enchant));\n        }\n        \n        List<String> results = new ArrayList<>();\n        for (Future<String> future : futures) {\n            try {\n                results.add(future.get());\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n                throw new RuntimeException(e);\n            }\n        }\n        return results;\n    }\n    \n    public List<Integer> traverseSequential(SigilNode root) {\n        List<Integer> results = new ArrayList<>();\n        traverseSequentialHelper(root, results);\n        return results;\n    }\n    \n    private void traverseSequentialHelper(SigilNode node, List<Integer> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode child : node.getChildren()) {\n            traverseSequentialHelper(child, results);\n        }\n    }\n    \n    public List<Integer> traverseParallel(SigilNode root) {\n        ConcurrentLinkedQueue<Integer> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = traverseParallelHelper(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new RuntimeException(e);\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private CountDownLatch traverseParallelHelper(SigilNode node, ConcurrentLinkedQueue<Integer> results) {\n        if (node == null) return new CountDownLatch(0);\n        \n        List<SigilNode> children = node.getChildren();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (SigilNode child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = traverseParallelHelper(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentEnchantment {\n    public static void main(String[] args) {\n        EnchantmentProcessor processor = new EnchantmentProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new SimpleTalisman(\"Alpha\"),\n            new SimpleTalisman(\"Beta\"),\n            new SimpleTalisman(\"Gamma\"),\n            new SimpleTalisman(\"Delta\")\n        );\n        \n        System.out.println(\"Sequential Talisman Enchantment:\");\n        long startTime = System.currentTimeMillis();\n        List<String> seqResults = processor.weaveSequential(talismans);\n        long seqTime = System.currentTimeMillis() - startTime;\n        seqResults.forEach(System.out::println);\n        System.out.println(\"Sequential time: \" + seqTime + \"ms\\n\");\n        \n        System.out.println(\"Parallel Talisman Enchantment:\");\n        startTime = System.currentTimeMillis();\n        List<String> parResults = processor.weaveParallel(talismans);\n        long parTime = System.currentTimeMillis() - startTime;\n        parResults.forEach(System.out::println);\n        System.out.println(\"Parallel time: \" + parTime + \"ms\\n\");\n        \n        SigilNode root = new SimpleSigilNode(1, Arrays.asList(\n            new SimpleSigilNode(2, Arrays.asList(\n                new SimpleSigilNode(4, Collections.emptyList()),\n                new SimpleSigilNode(5, Collections.emptyList())\n            )),\n            new SimpleSigilNode(3, Arrays.asList(\n                new SimpleSigilNode(6, Collections.emptyList()),\n                new SimpleSigilNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"Sequential Sigil Traversal:\");\n        startTime = System.currentTimeMillis();\n        List<Integer> seqSigilResults = processor.traverseSequential(root);\n        long seqSigilTime = System.currentTimeMillis() - startTime;\n        System.out.println(seqSigilResults);\n        System.out.println(\"Sequential sigil time: \" + seqSigilTime + \"ms\\n\");\n        \n        System.out.println(\"Parallel Sigil Traversal:\");\n        startTime = System.currentTimeMillis();\n        List<Integer> parSigilResults = processor.traverseParallel(root);\n        long parSigilTime = System.currentTimeMillis() - startTime;\n        System.out.println(parSigilResults);\n        System.out.println(\"Parallel sigil time: \" + parSigilTime + \"ms\");\n        \n        processor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.Collectors;\n\ninterface Talisman {\n    String enchant();\n}\n\ninterface SigilNode {\n    int compute();\n    List<SigilNode> getChildSigils();\n}\n\nclass ConcreteTalisman implements Talisman {\n    private final String name;\n    \n    public ConcreteTalisman(String name) {\n        this.name = name;\n    }\n    \n    public String enchant() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return \"Enchanted-\" + name;\n    }\n}\n\nclass ConcreteSigilNode implements SigilNode {\n    private final int value;\n    private final List<SigilNode> children;\n    \n    public ConcreteSigilNode(int value, List<SigilNode> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    public int compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value * 2;\n    }\n    \n    public List<SigilNode> getChildSigils() {\n        return children;\n    }\n}\n\nclass EnchantmentProcessor {\n    private final ExecutorService executor;\n    \n    public EnchantmentProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public List<String> weaveSequential(List<Talisman> talismans) {\n        List<String> results = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            results.add(talisman.enchant());\n        }\n        return results;\n    }\n    \n    public List<String> weaveParallel(List<Talisman> talismans) {\n        List<Future<String>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.enchant()));\n        }\n        \n        List<String> results = new ArrayList<>();\n        for (Future<String> future : futures) {\n            try {\n                results.add(future.get());\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        return results;\n    }\n    \n    public List<Integer> traverseSequential(SigilNode root) {\n        List<Integer> results = new ArrayList<>();\n        traverseSequentialHelper(root, results);\n        return results;\n    }\n    \n    private void traverseSequentialHelper(SigilNode node, List<Integer> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode child : node.getChildSigils()) {\n            traverseSequentialHelper(child, results);\n        }\n    }\n    \n    public List<Integer> traverseParallel(SigilNode root) {\n        ConcurrentLinkedQueue<Integer> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = new CountDownLatch(countNodes(root));\n        traverseParallelHelper(root, results, latch);\n        \n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        return new ArrayList<>(results);\n    }\n    \n    private void traverseParallelHelper(SigilNode node, ConcurrentLinkedQueue<Integer> results, CountDownLatch latch) {\n        if (node == null) return;\n        \n        executor.submit(() -> {\n            results.add(node.compute());\n            latch.countDown();\n        });\n        \n        for (SigilNode child : node.getChildSigils()) {\n            traverseParallelHelper(child, results, latch);\n        }\n    }\n    \n    private int countNodes(SigilNode node) {\n        if (node == null) return 0;\n        int count = 1;\n        for (SigilNode child : node.getChildSigils()) {\n            count += countNodes(child);\n        }\n        return count;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentEnchantment {\n    public static void main(String[] args) {\n        EnchantmentProcessor processor = new EnchantmentProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new ConcreteTalisman(\"Alpha\"),\n            new ConcreteTalisman(\"Beta\"),\n            new ConcreteTalisman(\"Gamma\"),\n            new ConcreteTalisman(\"Delta\")\n        );\n        \n        System.out.println(\"Sequential Talisman Processing:\");\n        List<String> seqResults = processor.weaveSequential(talismans);\n        seqResults.forEach(System.out::println);\n        \n        System.out.println(\"\\nParallel Talisman Processing:\");\n        List<String> parResults = processor.weaveParallel(talismans);\n        parResults.forEach(System.out::println);\n        \n        SigilNode root = new ConcreteSigilNode(1, Arrays.asList(\n            new ConcreteSigilNode(2, Arrays.asList(\n                new ConcreteSigilNode(4, new ArrayList<>()),\n                new ConcreteSigilNode(5, new ArrayList<>())\n            )),\n            new ConcreteSigilNode(3, Arrays.asList(\n                new ConcreteSigilNode(6, new ArrayList<>()),\n                new ConcreteSigilNode(7, new ArrayList<>())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential Sigil Traversal:\");\n        List<Integer> seqSigilResults = processor.traverseSequential(root);\n        System.out.println(seqSigilResults);\n        \n        System.out.println(\"\\nParallel Sigil Traversal:\");\n        List<Integer> parSigilResults = processor.traverseParallel(root);\n        System.out.println(parSigilResults);\n        \n        processor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\ninterface Talisman {\n    String enchant();\n}\n\ninterface SigilNode {\n    int compute();\n    List<SigilNode> getChildren();\n}\n\nclass SimpleTalisman implements Talisman {\n    private final String name;\n    \n    public SimpleTalisman(String name) {\n        this.name = name;\n    }\n    \n    public String enchant() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return \"Enchanted-\" + name;\n    }\n}\n\nclass SimpleSigilNode implements SigilNode {\n    private final int value;\n    private final List<SigilNode> children;\n    \n    public SimpleSigilNode(int value, List<SigilNode> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    public int compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value * 2;\n    }\n    \n    public List<SigilNode> getChildren() {\n        return new ArrayList<>(children);\n    }\n}\n\nclass EnchantmentProcessor {\n    private final ExecutorService executor;\n    \n    public EnchantmentProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public List<String> weaveSequential(List<Talisman> talismans) {\n        List<String> results = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            results.add(talisman.enchant());\n        }\n        return results;\n    }\n    \n    public List<String> weaveParallel(List<Talisman> talismans) {\n        List<Future<String>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.enchant()));\n        }\n        \n        List<String> results = new ArrayList<>();\n        for (Future<String> future : futures) {\n            try {\n                results.add(future.get());\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n                throw new RuntimeException(e);\n            }\n        }\n        return results;\n    }\n    \n    public List<Integer> traverseSequential(SigilNode root) {\n        List<Integer> results = new ArrayList<>();\n        traverseSequentialRecursive(root, results);\n        return results;\n    }\n    \n    private void traverseSequentialRecursive(SigilNode node, List<Integer> results) {\n        if (node == null) return;\n        \n        results.add(node.compute());\n        \n        for (SigilNode child : node.getChildren()) {\n            traverseSequentialRecursive(child, results);\n        }\n    }\n    \n    public List<Integer> traverseParallel(SigilNode root) {\n        ConcurrentLinkedQueue<Integer> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = traverseParallelRecursive(root, results);\n        \n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new RuntimeException(e);\n        }\n        \n        return new ArrayList<>(results);\n    }\n    \n    private CountDownLatch traverseParallelRecursive(SigilNode node, ConcurrentLinkedQueue<Integer> results) {\n        if (node == null) {\n            return new CountDownLatch(0);\n        }\n        \n        List<SigilNode> children = node.getChildren();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (SigilNode child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = traverseParallelRecursive(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentEnchantment {\n    public static void main(String[] args) {\n        EnchantmentProcessor processor = new EnchantmentProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new SimpleTalisman(\"Fire\"),\n            new SimpleTalisman(\"Water\"),\n            new SimpleTalisman(\"Earth\"),\n            new SimpleTalisman(\"Air\")\n        );\n        \n        System.out.println(\"Sequential Talisman Processing:\");\n        List<String> seqResults = processor.weaveSequential(talismans);\n        seqResults.forEach(System.out::println);\n        \n        System.out.println(\"\\nParallel Talisman Processing:\");\n        List<String> parResults = processor.weaveParallel(talismans);\n        parResults.forEach(System.out::println);\n        \n        SigilNode root = new SimpleSigilNode(1, Arrays.asList(\n            new SimpleSigilNode(2, Arrays.asList(\n                new SimpleSigilNode(4, Collections.emptyList()),\n                new SimpleSigilNode(5, Collections.emptyList())\n            )),\n            new SimpleSigilNode(3, Arrays.asList(\n                new SimpleSigilNode(6, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential Sigil Traversal:\");\n        List<Integer> seqSigilResults = processor.traverseSequential(root);\n        System.out.println(seqSigilResults);\n        \n        System.out.println(\"\\nParallel Sigil Traversal:\");\n        List<Integer> parSigilResults = processor.traverseParallel(root);\n        System.out.println(parSigilResults);\n        \n        processor.shutdown();\n    }\n}"
        ],
        "graded_list": [
            false,
            true,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\npublic abstract class LLMC {\n\nvoid processSequentially(List<Element> elements) {\nfor (Element e : elements)\nprocess(e);\n}\n\nvoid processInParallel(Executor exec, List<Element> elements) {\nCountDownLatch latch = new CountDownLatch(elements.size());\nfor (final Element e : elements) {\nexec.execute(() -> {\nprocess(e);\nlatch.countDown();\n});\n}\ntry {\nlatch.await();\n} catch (InterruptedException ie) {\nThread.currentThread().interrupt();\n}\n}\n\npublic abstract void process(Element e);\n\npublic <T> void sequentialRecursive(List<Node<T>> nodes, Collection<T> results) {\nfor (Node<T> n : nodes) {\nresults.add(n.compute());\nsequentialRecursive(n.getChildren(), results);\n}\n}\n\npublic <T> Collection<T> parallelRecursive(List<Node<T>> nodes) throws InterruptedException {\nCollection<T> results = Collections.synchronizedList(new ArrayList<>());\nCountDownLatch latch = new CountDownLatch(nodes.size());\n\nThread worker = new Thread(() -> {\nfor (Node<T> n : nodes) {\nT result = n.compute();\nresults.add(result);\nsequentialRecursive(n.getChildren(), results);\nlatch.countDown();\n}\n});\n\nworker.start();\nlatch.await();\n\nreturn results;\n}\n\ninterface Element {}\ninterface Node<T> { T compute(); List<Node<T>> getChildren(); }\n\nstatic class MyElement implements Element {\nprivate final String name;\npublic MyElement(String name) { this.name = name; }\npublic String toString() { return \"Element: \" + name; }\n}\n\nstatic class MyNode implements Node<String> {\nprivate final String name;\nprivate final List<Node<String>> children;\npublic MyNode(String name, List<Node<String>> children) {\nthis.name = name;\nthis.children = children != null ? children : Collections.emptyList();\n}\npublic String compute() {\nreturn name;\n}\npublic List<Node<String>> getChildren() { return children; }\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC instance = new LLMC() {\npublic void process(Element e) {\n// Minimal processing\n}\n};\n\nList<Element> elements = Arrays.asList(new MyElement(\"A\"));\n\ninstance.processSequentially(elements);\n\nThread executor = new Thread(() -> {\ninstance.processInParallel(Runnable::run, elements);\n});\nexecutor.start();\nexecutor.join();\n\nNode<String> leaf = new MyNode(\"Leaf\", null);\nNode<String> root = new MyNode(\"Root\", Arrays.asList(leaf));\nList<Node<String>> tree = Arrays.asList(root);\n\nCollection<String> sequentialResults = new ArrayList<>();\ninstance.sequentialRecursive(tree, sequentialResults);\n\nCollection<String> parallelResults = instance.parallelRecursive(tree);\nSystem.out.println(parallelResults);\n}\n}",
        "max_depth": "5979",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.38%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 8.28%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 46.90%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=145,visited=0,backtracked=0,end=1\nsearch:             maxDepth=145,constraints=0\nchoice generators:  thread=145 (signal=0,lock=6,sharedRef=121,threadApi=13,reschedule=0), data=0\nheap:               new=1296,released=150,maxLive=1135,gcCycles=141\ninstructions:       22608\nmax memory:         981MB\nloaded code:        classes=147,methods=2692\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 38.83%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 70.77%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 67.98%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=124598,visited=79761,backtracked=145052,end=1509\nsearch:             maxDepth=59790,constraints=20171\nchoice generators:  thread=113888 (signal=0,lock=6,sharedRef=90538,threadApi=19,reschedule=12689), data=0\nheap:               new=37515,released=613922,maxLive=1128,gcCycles=204356\ninstructions:       28478153\nmax memory:         1007MB\nloaded code:        classes=152,methods=2724\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.39%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 8.33%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 46.53%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=144,visited=0,backtracked=0,end=1\nsearch:             maxDepth=144,constraints=0\nchoice generators:  thread=144 (signal=0,lock=6,sharedRef=121,threadApi=12,reschedule=0), data=0\nheap:               new=1259,released=127,maxLive=1125,gcCycles=140\ninstructions:       21754\nmax memory:         981MB\nloaded code:        classes=147,methods=2693\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"",
            "no errors detected",
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\""
        ],
        "codebleu_score": [
            60.85,
            62.49,
            60.7
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\ninterface Talisman {\n    String enchant();\n}\n\ninterface SigilNode {\n    int compute();\n    List<SigilNode> getChildren();\n}\n\nclass SimpleTalisman implements Talisman {\n    private final String name;\n    \n    public SimpleTalisman(String name) {\n        this.name = name;\n    }\n    \n    public String enchant() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return \"Enchanted-\" + name;\n    }\n}\n\nclass SimpleSigilNode implements SigilNode {\n    private final int value;\n    private final List<SigilNode> children;\n    \n    public SimpleSigilNode(int value, List<SigilNode> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    public int compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value * 2;\n    }\n    \n    public List<SigilNode> getChildren() {\n        return new ArrayList<>(children);\n    }\n}\n\nclass EnchantmentProcessor {\n    private final ExecutorService executor;\n    \n    public EnchantmentProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public List<String> weaveSequential(List<Talisman> talismans) {\n        List<String> results = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            results.add(talisman.enchant());\n        }\n        return results;\n    }\n    \n    public List<String> weaveParallel(List<Talisman> talismans) {\n        List<Future<String>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(talisman::enchant));\n        }\n        \n        List<String> results = new ArrayList<>();\n        for (Future<String> future : futures) {\n            try {\n                results.add(future.get());\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n                throw new RuntimeException(e);\n            }\n        }\n        return results;\n    }\n    \n    public List<Integer> traverseSequential(SigilNode root) {\n        List<Integer> results = new ArrayList<>();\n        traverseSequentialHelper(root, results);\n        return results;\n    }\n    \n    private void traverseSequentialHelper(SigilNode node, List<Integer> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode child : node.getChildren()) {\n            traverseSequentialHelper(child, results);\n        }\n    }\n    \n    public List<Integer> traverseParallel(SigilNode root) {\n        ConcurrentLinkedQueue<Integer> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = traverseParallelHelper(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new RuntimeException(e);\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private CountDownLatch traverseParallelHelper(SigilNode node, ConcurrentLinkedQueue<Integer> results) {\n        if (node == null) return new CountDownLatch(0);\n        \n        List<SigilNode> children = node.getChildren();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (SigilNode child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = traverseParallelHelper(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentEnchantment {\n    public static void main(String[] args) {\n        EnchantmentProcessor processor = new EnchantmentProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new SimpleTalisman(\"Alpha\"),\n            new SimpleTalisman(\"Beta\"),\n            new SimpleTalisman(\"Gamma\"),\n            new SimpleTalisman(\"Delta\")\n        );\n        \n        System.out.println(\"Sequential Talisman Enchantment:\");\n        long startTime = System.currentTimeMillis();\n        List<String> seqResults = processor.weaveSequential(talismans);\n        long seqTime = System.currentTimeMillis() - startTime;\n        seqResults.forEach(System.out::println);\n        System.out.println(\"Sequential time: \" + seqTime + \"ms\\n\");\n        \n        System.out.println(\"Parallel Talisman Enchantment:\");\n        startTime = System.currentTimeMillis();\n        List<String> parResults = processor.weaveParallel(talismans);\n        long parTime = System.currentTimeMillis() - startTime;\n        parResults.forEach(System.out::println);\n        System.out.println(\"Parallel time: \" + parTime + \"ms\\n\");\n        \n        SigilNode root = new SimpleSigilNode(1, Arrays.asList(\n            new SimpleSigilNode(2, Arrays.asList(\n                new SimpleSigilNode(4, Collections.emptyList()),\n                new SimpleSigilNode(5, Collections.emptyList())\n            )),\n            new SimpleSigilNode(3, Arrays.asList(\n                new SimpleSigilNode(6, Collections.emptyList()),\n                new SimpleSigilNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"Sequential Sigil Traversal:\");\n        startTime = System.currentTimeMillis();\n        List<Integer> seqSigilResults = processor.traverseSequential(root);\n        long seqSigilTime = System.currentTimeMillis() - startTime;\n        System.out.println(seqSigilResults);\n        System.out.println(\"Sequential sigil time: \" + seqSigilTime + \"ms\\n\");\n        \n        System.out.println(\"Parallel Sigil Traversal:\");\n        startTime = System.currentTimeMillis();\n        List<Integer> parSigilResults = processor.traverseParallel(root);\n        long parSigilTime = System.currentTimeMillis() - startTime;\n        System.out.println(parSigilResults);\n        System.out.println(\"Parallel sigil time: \" + parSigilTime + \"ms\");\n        \n        processor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.Collectors;\n\ninterface Talisman {\n    String enchant();\n}\n\ninterface SigilNode {\n    int compute();\n    List<SigilNode> getChildSigils();\n}\n\nclass ConcreteTalisman implements Talisman {\n    private final String name;\n    \n    public ConcreteTalisman(String name) {\n        this.name = name;\n    }\n    \n    public String enchant() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return \"Enchanted-\" + name;\n    }\n}\n\nclass ConcreteSigilNode implements SigilNode {\n    private final int value;\n    private final List<SigilNode> children;\n    \n    public ConcreteSigilNode(int value, List<SigilNode> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    public int compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value * 2;\n    }\n    \n    public List<SigilNode> getChildSigils() {\n        return children;\n    }\n}\n\nclass EnchantmentProcessor {\n    private final ExecutorService executor;\n    \n    public EnchantmentProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public List<String> weaveSequential(List<Talisman> talismans) {\n        List<String> results = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            results.add(talisman.enchant());\n        }\n        return results;\n    }\n    \n    public List<String> weaveParallel(List<Talisman> talismans) {\n        List<Future<String>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.enchant()));\n        }\n        \n        List<String> results = new ArrayList<>();\n        for (Future<String> future : futures) {\n            try {\n                results.add(future.get());\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        return results;\n    }\n    \n    public List<Integer> traverseSequential(SigilNode root) {\n        List<Integer> results = new ArrayList<>();\n        traverseSequentialHelper(root, results);\n        return results;\n    }\n    \n    private void traverseSequentialHelper(SigilNode node, List<Integer> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode child : node.getChildSigils()) {\n            traverseSequentialHelper(child, results);\n        }\n    }\n    \n    public List<Integer> traverseParallel(SigilNode root) {\n        ConcurrentLinkedQueue<Integer> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = new CountDownLatch(countNodes(root));\n        traverseParallelHelper(root, results, latch);\n        \n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        return new ArrayList<>(results);\n    }\n    \n    private void traverseParallelHelper(SigilNode node, ConcurrentLinkedQueue<Integer> results, CountDownLatch latch) {\n        if (node == null) return;\n        \n        executor.submit(() -> {\n            results.add(node.compute());\n            latch.countDown();\n        });\n        \n        for (SigilNode child : node.getChildSigils()) {\n            traverseParallelHelper(child, results, latch);\n        }\n    }\n    \n    private int countNodes(SigilNode node) {\n        if (node == null) return 0;\n        int count = 1;\n        for (SigilNode child : node.getChildSigils()) {\n            count += countNodes(child);\n        }\n        return count;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentEnchantment {\n    public static void main(String[] args) {\n        EnchantmentProcessor processor = new EnchantmentProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new ConcreteTalisman(\"Alpha\"),\n            new ConcreteTalisman(\"Beta\"),\n            new ConcreteTalisman(\"Gamma\"),\n            new ConcreteTalisman(\"Delta\")\n        );\n        \n        System.out.println(\"Sequential Talisman Processing:\");\n        List<String> seqResults = processor.weaveSequential(talismans);\n        seqResults.forEach(System.out::println);\n        \n        System.out.println(\"\\nParallel Talisman Processing:\");\n        List<String> parResults = processor.weaveParallel(talismans);\n        parResults.forEach(System.out::println);\n        \n        SigilNode root = new ConcreteSigilNode(1, Arrays.asList(\n            new ConcreteSigilNode(2, Arrays.asList(\n                new ConcreteSigilNode(4, new ArrayList<>()),\n                new ConcreteSigilNode(5, new ArrayList<>())\n            )),\n            new ConcreteSigilNode(3, Arrays.asList(\n                new ConcreteSigilNode(6, new ArrayList<>()),\n                new ConcreteSigilNode(7, new ArrayList<>())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential Sigil Traversal:\");\n        List<Integer> seqSigilResults = processor.traverseSequential(root);\n        System.out.println(seqSigilResults);\n        \n        System.out.println(\"\\nParallel Sigil Traversal:\");\n        List<Integer> parSigilResults = processor.traverseParallel(root);\n        System.out.println(parSigilResults);\n        \n        processor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\ninterface Talisman {\n    String enchant();\n}\n\ninterface SigilNode {\n    int compute();\n    List<SigilNode> getChildren();\n}\n\nclass SimpleTalisman implements Talisman {\n    private final String name;\n    \n    public SimpleTalisman(String name) {\n        this.name = name;\n    }\n    \n    public String enchant() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return \"Enchanted-\" + name;\n    }\n}\n\nclass SimpleSigilNode implements SigilNode {\n    private final int value;\n    private final List<SigilNode> children;\n    \n    public SimpleSigilNode(int value, List<SigilNode> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    public int compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value * 2;\n    }\n    \n    public List<SigilNode> getChildren() {\n        return new ArrayList<>(children);\n    }\n}\n\nclass EnchantmentProcessor {\n    private final ExecutorService executor;\n    \n    public EnchantmentProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public List<String> weaveSequential(List<Talisman> talismans) {\n        List<String> results = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            results.add(talisman.enchant());\n        }\n        return results;\n    }\n    \n    public List<String> weaveParallel(List<Talisman> talismans) {\n        List<Future<String>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.enchant()));\n        }\n        \n        List<String> results = new ArrayList<>();\n        for (Future<String> future : futures) {\n            try {\n                results.add(future.get());\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n                throw new RuntimeException(e);\n            }\n        }\n        return results;\n    }\n    \n    public List<Integer> traverseSequential(SigilNode root) {\n        List<Integer> results = new ArrayList<>();\n        traverseSequentialRecursive(root, results);\n        return results;\n    }\n    \n    private void traverseSequentialRecursive(SigilNode node, List<Integer> results) {\n        if (node == null) return;\n        \n        results.add(node.compute());\n        \n        for (SigilNode child : node.getChildren()) {\n            traverseSequentialRecursive(child, results);\n        }\n    }\n    \n    public List<Integer> traverseParallel(SigilNode root) {\n        ConcurrentLinkedQueue<Integer> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = traverseParallelRecursive(root, results);\n        \n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new RuntimeException(e);\n        }\n        \n        return new ArrayList<>(results);\n    }\n    \n    private CountDownLatch traverseParallelRecursive(SigilNode node, ConcurrentLinkedQueue<Integer> results) {\n        if (node == null) {\n            return new CountDownLatch(0);\n        }\n        \n        List<SigilNode> children = node.getChildren();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (SigilNode child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = traverseParallelRecursive(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentEnchantment {\n    public static void main(String[] args) {\n        EnchantmentProcessor processor = new EnchantmentProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new SimpleTalisman(\"Fire\"),\n            new SimpleTalisman(\"Water\"),\n            new SimpleTalisman(\"Earth\"),\n            new SimpleTalisman(\"Air\")\n        );\n        \n        System.out.println(\"Sequential Talisman Processing:\");\n        List<String> seqResults = processor.weaveSequential(talismans);\n        seqResults.forEach(System.out::println);\n        \n        System.out.println(\"\\nParallel Talisman Processing:\");\n        List<String> parResults = processor.weaveParallel(talismans);\n        parResults.forEach(System.out::println);\n        \n        SigilNode root = new SimpleSigilNode(1, Arrays.asList(\n            new SimpleSigilNode(2, Arrays.asList(\n                new SimpleSigilNode(4, Collections.emptyList()),\n                new SimpleSigilNode(5, Collections.emptyList())\n            )),\n            new SimpleSigilNode(3, Arrays.asList(\n                new SimpleSigilNode(6, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential Sigil Traversal:\");\n        List<Integer> seqSigilResults = processor.traverseSequential(root);\n        System.out.println(seqSigilResults);\n        \n        System.out.println(\"\\nParallel Sigil Traversal:\");\n        List<Integer> parSigilResults = processor.traverseParallel(root);\n        System.out.println(parSigilResults);\n        \n        processor.shutdown();\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Waiting for results to be calculated in parallel. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write Java code that transforms sequential incantation into concurrent spellcasting using an Executor. The code should include two main processing methods: one that processes a list of charms sequentially by iterating and invoking each charm in turn, and another that submits each charm for parallel invocation via an executor. Additionally, implement recursive versions of both sequential and parallel processing methods that traverse a crystal-tree structure of runes, computing results and collecting them in a thread-safe manner. The parallel version should properly employ an ExecutorService to run tasks concurrently, ensure all tasks complete before returning the final result collection, and use appropriate concurrency utilities for thread safety. Define interfaces Charm and RuneNode, where RuneNode supports computation and retrieval of child runes. Ensure the design follows good abstraction principles and includes proper generic typing. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\ninterface Charm {\n    void invoke();\n}\n\ninterface RuneNode<T> {\n    T compute();\n    List<RuneNode<T>> getChildRunes();\n}\n\nclass SpellCaster {\n    private final ExecutorService executor;\n    \n    public SpellCaster(ExecutorService executor) {\n        this.executor = executor;\n    }\n    \n    public void processCharmsSequentially(List<Charm> charms) {\n        for (Charm charm : charms) {\n            charm.invoke();\n        }\n    }\n    \n    public void processCharmsParallel(List<Charm> charms) throws InterruptedException {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Charm charm : charms) {\n            futures.add(executor.submit(() -> charm.invoke()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (ExecutionException e) {\n                throw new RuntimeException(e);\n            }\n        }\n    }\n    \n    public <T> List<T> traverseRunesSequentially(RuneNode<T> root) {\n        List<T> results = new ArrayList<>();\n        traverseSequentialHelper(root, results);\n        return results;\n    }\n    \n    private <T> void traverseSequentialHelper(RuneNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (RuneNode<T> child : node.getChildRunes()) {\n            traverseSequentialHelper(child, results);\n        }\n    }\n    \n    public <T> List<T> traverseRunesParallel(RuneNode<T> root) throws InterruptedException {\n        ConcurrentLinkedQueue<T> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = traverseParallelHelper(root, results);\n        latch.await();\n        return new ArrayList<>(results);\n    }\n    \n    private <T> CountDownLatch traverseParallelHelper(RuneNode<T> node, ConcurrentLinkedQueue<T> results) {\n        if (node == null) return new CountDownLatch(0);\n        \n        List<RuneNode<T>> children = node.getChildRunes();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (RuneNode<T> child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = traverseParallelHelper(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n}\n\nclass SimpleCharm implements Charm {\n    private final String name;\n    \n    public SimpleCharm(String name) {\n        this.name = name;\n    }\n    \n    public void invoke() {\n        System.out.println(\"Invoking charm: \" + name + \" on thread: \" + Thread.currentThread().getName());\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass SimpleRuneNode implements RuneNode<Integer> {\n    private final int value;\n    private final List<RuneNode<Integer>> children;\n    \n    public SimpleRuneNode(int value, List<RuneNode<Integer>> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    public Integer compute() {\n        System.out.println(\"Computing rune: \" + value + \" on thread: \" + Thread.currentThread().getName());\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value * 2;\n    }\n    \n    public List<RuneNode<Integer>> getChildRunes() {\n        return children;\n    }\n}\n\npublic class ConcurrentSpellcasting {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        SpellCaster caster = new SpellCaster(executor);\n        \n        List<Charm> charms = Arrays.asList(\n            new SimpleCharm(\"Fire\"),\n            new SimpleCharm(\"Ice\"),\n            new SimpleCharm(\"Lightning\"),\n            new SimpleCharm(\"Earth\")\n        );\n        \n        System.out.println(\"Sequential Charm Processing:\");\n        caster.processCharmsSequentially(charms);\n        \n        System.out.println(\"\\nParallel Charm Processing:\");\n        caster.processCharmsParallel(charms);\n        \n        RuneNode<Integer> runeTree = new SimpleRuneNode(1, Arrays.asList(\n            new SimpleRuneNode(2, Arrays.asList(\n                new SimpleRuneNode(4, Collections.emptyList()),\n                new SimpleRuneNode(5, Collections.emptyList())\n            )),\n            new SimpleRuneNode(3, Arrays.asList(\n                new SimpleRuneNode(6, Collections.emptyList()),\n                new SimpleRuneNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential Rune Traversal:\");\n        List<Integer> sequentialResults = caster.traverseRunesSequentially(runeTree);\n        System.out.println(\"Sequential Results: \" + sequentialResults);\n        \n        System.out.println(\"\\nParallel Rune Traversal:\");\n        List<Integer> parallelResults = caster.traverseRunesParallel(runeTree);\n        System.out.println(\"Parallel Results: \" + parallelResults);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\ninterface Charm {\n    void invoke();\n}\n\ninterface RuneNode<T> {\n    T compute();\n    List<RuneNode<T>> getChildRunes();\n}\n\nclass SimpleCharm implements Charm {\n    private final String name;\n    \n    public SimpleCharm(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void invoke() {\n        System.out.println(\"Invoking charm: \" + name);\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass SimpleRuneNode implements RuneNode<Integer> {\n    private final int value;\n    private final List<RuneNode<Integer>> children;\n    \n    public SimpleRuneNode(int value, List<RuneNode<Integer>> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    @Override\n    public Integer compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<RuneNode<Integer>> getChildRunes() {\n        return new ArrayList<>(children);\n    }\n}\n\nclass SpellCaster {\n    private final ExecutorService executor;\n    \n    public SpellCaster() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processCharmsSequentially(List<Charm> charms) {\n        for (Charm charm : charms) {\n            charm.invoke();\n        }\n    }\n    \n    public void processCharmsConcurrently(List<Charm> charms) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Charm charm : charms) {\n            futures.add(executor.submit(() -> charm.invoke()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> processRuneTreeSequentially(RuneNode<T> root) {\n        List<T> results = new ArrayList<>();\n        processRuneTreeSequentiallyRecursive(root, results);\n        return results;\n    }\n    \n    private <T> void processRuneTreeSequentiallyRecursive(RuneNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (RuneNode<T> child : node.getChildRunes()) {\n            processRuneTreeSequentiallyRecursive(child, results);\n        }\n    }\n    \n    public <T> List<T> processRuneTreeConcurrently(RuneNode<T> root) {\n        List<T> results = new CopyOnWriteArrayList<>();\n        CountDownLatch latch = processRuneTreeConcurrentlyRecursive(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> CountDownLatch processRuneTreeConcurrentlyRecursive(RuneNode<T> node, List<T> results) {\n        if (node == null) {\n            return new CountDownLatch(0);\n        }\n        \n        List<RuneNode<T>> children = node.getChildRunes();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (RuneNode<T> child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = processRuneTreeConcurrentlyRecursive(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentSpellcasting {\n    public static void main(String[] args) {\n        SpellCaster caster = new SpellCaster();\n        \n        List<Charm> charms = Arrays.asList(\n            new SimpleCharm(\"Fire\"),\n            new SimpleCharm(\"Water\"),\n            new SimpleCharm(\"Earth\"),\n            new SimpleCharm(\"Air\")\n        );\n        \n        System.out.println(\"Sequential charm processing:\");\n        caster.processCharmsSequentially(charms);\n        \n        System.out.println(\"\\nConcurrent charm processing:\");\n        caster.processCharmsConcurrently(charms);\n        \n        SimpleRuneNode root = new SimpleRuneNode(1, Arrays.asList(\n            new SimpleRuneNode(2, Arrays.asList(\n                new SimpleRuneNode(4, Collections.emptyList()),\n                new SimpleRuneNode(5, Collections.emptyList())\n            )),\n            new SimpleRuneNode(3, Arrays.asList(\n                new SimpleRuneNode(6, Collections.emptyList()),\n                new SimpleRuneNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential rune tree processing:\");\n        List<Integer> seqResults = caster.processRuneTreeSequentially(root);\n        System.out.println(\"Results: \" + seqResults);\n        \n        System.out.println(\"\\nConcurrent rune tree processing:\");\n        List<Integer> concResults = caster.processRuneTreeConcurrently(root);\n        System.out.println(\"Results: \" + concResults);\n        \n        caster.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\ninterface Charm {\n    void invoke();\n}\n\ninterface RuneNode<T> {\n    T compute();\n    List<RuneNode<T>> getChildRunes();\n}\n\nclass SimpleCharm implements Charm {\n    private final String name;\n    \n    public SimpleCharm(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void invoke() {\n        System.out.println(\"Invoking charm: \" + name);\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass SimpleRuneNode implements RuneNode<Integer> {\n    private final int value;\n    private final List<RuneNode<Integer>> children;\n    \n    public SimpleRuneNode(int value, List<RuneNode<Integer>> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    @Override\n    public Integer compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<RuneNode<Integer>> getChildRunes() {\n        return new ArrayList<>(children);\n    }\n}\n\nclass SpellCaster {\n    private final ExecutorService executor;\n    \n    public SpellCaster() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processCharmsSequentially(List<Charm> charms) {\n        for (Charm charm : charms) {\n            charm.invoke();\n        }\n    }\n    \n    public void processCharmsConcurrently(List<Charm> charms) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Charm charm : charms) {\n            futures.add(executor.submit(() -> charm.invoke()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> processRuneTreeSequentially(RuneNode<T> root) {\n        List<T> results = new ArrayList<>();\n        processRuneTreeSequentiallyRecursive(root, results);\n        return results;\n    }\n    \n    private <T> void processRuneTreeSequentiallyRecursive(RuneNode<T> node, List<T> results) {\n        if (node == null) {\n            return;\n        }\n        results.add(node.compute());\n        for (RuneNode<T> child : node.getChildRunes()) {\n            processRuneTreeSequentiallyRecursive(child, results);\n        }\n    }\n    \n    public <T> List<T> processRuneTreeConcurrently(RuneNode<T> root) {\n        ConcurrentLinkedQueue<T> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = new CountDownLatch(1);\n        processRuneTreeConcurrentlyRecursive(root, results, latch);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> void processRuneTreeConcurrentlyRecursive(RuneNode<T> node, ConcurrentLinkedQueue<T> results, CountDownLatch parentLatch) {\n        if (node == null) {\n            parentLatch.countDown();\n            return;\n        }\n        \n        executor.submit(() -> {\n            results.add(node.compute());\n            List<RuneNode<T>> children = node.getChildRunes();\n            if (children.isEmpty()) {\n                parentLatch.countDown();\n            } else {\n                CountDownLatch childLatch = new CountDownLatch(children.size());\n                for (RuneNode<T> child : children) {\n                    processRuneTreeConcurrentlyRecursive(child, results, childLatch);\n                }\n                try {\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                parentLatch.countDown();\n            }\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentSpellcasting {\n    public static void main(String[] args) {\n        SpellCaster caster = new SpellCaster();\n        \n        List<Charm> charms = Arrays.asList(\n            new SimpleCharm(\"Fire\"),\n            new SimpleCharm(\"Water\"),\n            new SimpleCharm(\"Earth\"),\n            new SimpleCharm(\"Air\")\n        );\n        \n        System.out.println(\"Sequential charm processing:\");\n        long startTime = System.currentTimeMillis();\n        caster.processCharmsSequentially(charms);\n        System.out.println(\"Sequential time: \" + (System.currentTimeMillis() - startTime) + \"ms\");\n        \n        System.out.println(\"\\nConcurrent charm processing:\");\n        startTime = System.currentTimeMillis();\n        caster.processCharmsConcurrently(charms);\n        System.out.println(\"Concurrent time: \" + (System.currentTimeMillis() - startTime) + \"ms\");\n        \n        RuneNode<Integer> root = new SimpleRuneNode(1, Arrays.asList(\n            new SimpleRuneNode(2, Arrays.asList(\n                new SimpleRuneNode(4, Collections.emptyList()),\n                new SimpleRuneNode(5, Collections.emptyList())\n            )),\n            new SimpleRuneNode(3, Arrays.asList(\n                new SimpleRuneNode(6, Collections.emptyList()),\n                new SimpleRuneNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential rune tree processing:\");\n        startTime = System.currentTimeMillis();\n        List<Integer> sequentialResults = caster.processRuneTreeSequentially(root);\n        System.out.println(\"Results: \" + sequentialResults);\n        System.out.println(\"Sequential time: \" + (System.currentTimeMillis() - startTime) + \"ms\");\n        \n        System.out.println(\"\\nConcurrent rune tree processing:\");\n        startTime = System.currentTimeMillis();\n        List<Integer> concurrentResults = caster.processRuneTreeConcurrently(root);\n        System.out.println(\"Results: \" + concurrentResults);\n        System.out.println(\"Concurrent time: \" + (System.currentTimeMillis() - startTime) + \"ms\");\n        \n        caster.shutdown();\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\npublic abstract class LLMC {\n\nvoid processSequentially(List<Element> elements) {\nfor (Element e : elements)\nprocess(e);\n}\n\nvoid processInParallel(Executor exec, List<Element> elements) {\nCountDownLatch latch = new CountDownLatch(elements.size());\nfor (final Element e : elements) {\nexec.execute(() -> {\nprocess(e);\nlatch.countDown();\n});\n}\ntry {\nlatch.await();\n} catch (InterruptedException ie) {\nThread.currentThread().interrupt();\n}\n}\n\npublic abstract void process(Element e);\n\npublic <T> void sequentialRecursive(List<Node<T>> nodes, Collection<T> results) {\nfor (Node<T> n : nodes) {\nresults.add(n.compute());\nsequentialRecursive(n.getChildren(), results);\n}\n}\n\npublic <T> Collection<T> parallelRecursive(List<Node<T>> nodes) throws InterruptedException {\nCollection<T> results = Collections.synchronizedList(new ArrayList<>());\nCountDownLatch latch = new CountDownLatch(nodes.size());\n\nThread worker = new Thread(() -> {\nfor (Node<T> n : nodes) {\nT result = n.compute();\nresults.add(result);\nsequentialRecursive(n.getChildren(), results);\nlatch.countDown();\n}\n});\n\nworker.start();\nlatch.await();\n\nreturn results;\n}\n\ninterface Element {}\ninterface Node<T> { T compute(); List<Node<T>> getChildren(); }\n\nstatic class MyElement implements Element {\nprivate final String name;\npublic MyElement(String name) { this.name = name; }\npublic String toString() { return \"Element: \" + name; }\n}\n\nstatic class MyNode implements Node<String> {\nprivate final String name;\nprivate final List<Node<String>> children;\npublic MyNode(String name, List<Node<String>> children) {\nthis.name = name;\nthis.children = children != null ? children : Collections.emptyList();\n}\npublic String compute() {\nreturn name;\n}\npublic List<Node<String>> getChildren() { return children; }\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC instance = new LLMC() {\npublic void process(Element e) {\n// Minimal processing\n}\n};\n\nList<Element> elements = Arrays.asList(new MyElement(\"A\"));\n\ninstance.processSequentially(elements);\n\nThread executor = new Thread(() -> {\ninstance.processInParallel(Runnable::run, elements);\n});\nexecutor.start();\nexecutor.join();\n\nNode<String> leaf = new MyNode(\"Leaf\", null);\nNode<String> root = new MyNode(\"Root\", Arrays.asList(leaf));\nList<Node<String>> tree = Arrays.asList(root);\n\nCollection<String> sequentialResults = new ArrayList<>();\ninstance.sequentialRecursive(tree, sequentialResults);\n\nCollection<String> parallelResults = instance.parallelRecursive(tree);\nSystem.out.println(parallelResults);\n}\n}",
        "max_depth": "5979",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.37%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 8.22%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.32%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=146,visited=0,backtracked=0,end=1\nsearch:             maxDepth=146,constraints=0\nchoice generators:  thread=146 (signal=0,lock=7,sharedRef=119,threadApi=13,reschedule=2), data=0\nheap:               new=1311,released=193,maxLive=1107,gcCycles=145\ninstructions:       21124\nmax memory:         981MB\nloaded code:        classes=147,methods=2696\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.45%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 8.70%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 46.38%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=138,visited=0,backtracked=0,end=1\nsearch:             maxDepth=138,constraints=0\nchoice generators:  thread=138 (signal=0,lock=5,sharedRef=115,threadApi=13,reschedule=0), data=0\nheap:               new=1274,released=162,maxLive=1102,gcCycles=136\ninstructions:       21921\nmax memory:         981MB\nloaded code:        classes=145,methods=2713\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.64%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 9.84%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 39.34%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=122,visited=0,backtracked=0,end=1\nsearch:             maxDepth=122,constraints=0\nchoice generators:  thread=122 (signal=0,lock=6,sharedRef=98,threadApi=13,reschedule=0), data=0\nheap:               new=1278,released=166,maxLive=1101,gcCycles=121\ninstructions:       20249\nmax memory:         981MB\nloaded code:        classes=146,methods=2688\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"",
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"",
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\""
        ],
        "codebleu_score": [
            60.37,
            63.67,
            65.15
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\ninterface Charm {\n    void invoke();\n}\n\ninterface RuneNode<T> {\n    T compute();\n    List<RuneNode<T>> getChildRunes();\n}\n\nclass SpellCaster {\n    private final ExecutorService executor;\n    \n    public SpellCaster(ExecutorService executor) {\n        this.executor = executor;\n    }\n    \n    public void processCharmsSequentially(List<Charm> charms) {\n        for (Charm charm : charms) {\n            charm.invoke();\n        }\n    }\n    \n    public void processCharmsParallel(List<Charm> charms) throws InterruptedException {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Charm charm : charms) {\n            futures.add(executor.submit(() -> charm.invoke()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (ExecutionException e) {\n                throw new RuntimeException(e);\n            }\n        }\n    }\n    \n    public <T> List<T> traverseRunesSequentially(RuneNode<T> root) {\n        List<T> results = new ArrayList<>();\n        traverseSequentialHelper(root, results);\n        return results;\n    }\n    \n    private <T> void traverseSequentialHelper(RuneNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (RuneNode<T> child : node.getChildRunes()) {\n            traverseSequentialHelper(child, results);\n        }\n    }\n    \n    public <T> List<T> traverseRunesParallel(RuneNode<T> root) throws InterruptedException {\n        ConcurrentLinkedQueue<T> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = traverseParallelHelper(root, results);\n        latch.await();\n        return new ArrayList<>(results);\n    }\n    \n    private <T> CountDownLatch traverseParallelHelper(RuneNode<T> node, ConcurrentLinkedQueue<T> results) {\n        if (node == null) return new CountDownLatch(0);\n        \n        List<RuneNode<T>> children = node.getChildRunes();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (RuneNode<T> child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = traverseParallelHelper(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n}\n\nclass SimpleCharm implements Charm {\n    private final String name;\n    \n    public SimpleCharm(String name) {\n        this.name = name;\n    }\n    \n    public void invoke() {\n        System.out.println(\"Invoking charm: \" + name + \" on thread: \" + Thread.currentThread().getName());\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass SimpleRuneNode implements RuneNode<Integer> {\n    private final int value;\n    private final List<RuneNode<Integer>> children;\n    \n    public SimpleRuneNode(int value, List<RuneNode<Integer>> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    public Integer compute() {\n        System.out.println(\"Computing rune: \" + value + \" on thread: \" + Thread.currentThread().getName());\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value * 2;\n    }\n    \n    public List<RuneNode<Integer>> getChildRunes() {\n        return children;\n    }\n}\n\npublic class ConcurrentSpellcasting {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        SpellCaster caster = new SpellCaster(executor);\n        \n        List<Charm> charms = Arrays.asList(\n            new SimpleCharm(\"Fire\"),\n            new SimpleCharm(\"Ice\"),\n            new SimpleCharm(\"Lightning\"),\n            new SimpleCharm(\"Earth\")\n        );\n        \n        System.out.println(\"Sequential Charm Processing:\");\n        caster.processCharmsSequentially(charms);\n        \n        System.out.println(\"\\nParallel Charm Processing:\");\n        caster.processCharmsParallel(charms);\n        \n        RuneNode<Integer> runeTree = new SimpleRuneNode(1, Arrays.asList(\n            new SimpleRuneNode(2, Arrays.asList(\n                new SimpleRuneNode(4, Collections.emptyList()),\n                new SimpleRuneNode(5, Collections.emptyList())\n            )),\n            new SimpleRuneNode(3, Arrays.asList(\n                new SimpleRuneNode(6, Collections.emptyList()),\n                new SimpleRuneNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential Rune Traversal:\");\n        List<Integer> sequentialResults = caster.traverseRunesSequentially(runeTree);\n        System.out.println(\"Sequential Results: \" + sequentialResults);\n        \n        System.out.println(\"\\nParallel Rune Traversal:\");\n        List<Integer> parallelResults = caster.traverseRunesParallel(runeTree);\n        System.out.println(\"Parallel Results: \" + parallelResults);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\ninterface Charm {\n    void invoke();\n}\n\ninterface RuneNode<T> {\n    T compute();\n    List<RuneNode<T>> getChildRunes();\n}\n\nclass SimpleCharm implements Charm {\n    private final String name;\n    \n    public SimpleCharm(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void invoke() {\n        System.out.println(\"Invoking charm: \" + name);\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass SimpleRuneNode implements RuneNode<Integer> {\n    private final int value;\n    private final List<RuneNode<Integer>> children;\n    \n    public SimpleRuneNode(int value, List<RuneNode<Integer>> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    @Override\n    public Integer compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<RuneNode<Integer>> getChildRunes() {\n        return new ArrayList<>(children);\n    }\n}\n\nclass SpellCaster {\n    private final ExecutorService executor;\n    \n    public SpellCaster() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processCharmsSequentially(List<Charm> charms) {\n        for (Charm charm : charms) {\n            charm.invoke();\n        }\n    }\n    \n    public void processCharmsConcurrently(List<Charm> charms) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Charm charm : charms) {\n            futures.add(executor.submit(() -> charm.invoke()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> processRuneTreeSequentially(RuneNode<T> root) {\n        List<T> results = new ArrayList<>();\n        processRuneTreeSequentiallyRecursive(root, results);\n        return results;\n    }\n    \n    private <T> void processRuneTreeSequentiallyRecursive(RuneNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (RuneNode<T> child : node.getChildRunes()) {\n            processRuneTreeSequentiallyRecursive(child, results);\n        }\n    }\n    \n    public <T> List<T> processRuneTreeConcurrently(RuneNode<T> root) {\n        List<T> results = new CopyOnWriteArrayList<>();\n        CountDownLatch latch = processRuneTreeConcurrentlyRecursive(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> CountDownLatch processRuneTreeConcurrentlyRecursive(RuneNode<T> node, List<T> results) {\n        if (node == null) {\n            return new CountDownLatch(0);\n        }\n        \n        List<RuneNode<T>> children = node.getChildRunes();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (RuneNode<T> child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = processRuneTreeConcurrentlyRecursive(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentSpellcasting {\n    public static void main(String[] args) {\n        SpellCaster caster = new SpellCaster();\n        \n        List<Charm> charms = Arrays.asList(\n            new SimpleCharm(\"Fire\"),\n            new SimpleCharm(\"Water\"),\n            new SimpleCharm(\"Earth\"),\n            new SimpleCharm(\"Air\")\n        );\n        \n        System.out.println(\"Sequential charm processing:\");\n        caster.processCharmsSequentially(charms);\n        \n        System.out.println(\"\\nConcurrent charm processing:\");\n        caster.processCharmsConcurrently(charms);\n        \n        SimpleRuneNode root = new SimpleRuneNode(1, Arrays.asList(\n            new SimpleRuneNode(2, Arrays.asList(\n                new SimpleRuneNode(4, Collections.emptyList()),\n                new SimpleRuneNode(5, Collections.emptyList())\n            )),\n            new SimpleRuneNode(3, Arrays.asList(\n                new SimpleRuneNode(6, Collections.emptyList()),\n                new SimpleRuneNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential rune tree processing:\");\n        List<Integer> seqResults = caster.processRuneTreeSequentially(root);\n        System.out.println(\"Results: \" + seqResults);\n        \n        System.out.println(\"\\nConcurrent rune tree processing:\");\n        List<Integer> concResults = caster.processRuneTreeConcurrently(root);\n        System.out.println(\"Results: \" + concResults);\n        \n        caster.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\ninterface Charm {\n    void invoke();\n}\n\ninterface RuneNode<T> {\n    T compute();\n    List<RuneNode<T>> getChildRunes();\n}\n\nclass SimpleCharm implements Charm {\n    private final String name;\n    \n    public SimpleCharm(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void invoke() {\n        System.out.println(\"Invoking charm: \" + name);\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass SimpleRuneNode implements RuneNode<Integer> {\n    private final int value;\n    private final List<RuneNode<Integer>> children;\n    \n    public SimpleRuneNode(int value, List<RuneNode<Integer>> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    @Override\n    public Integer compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<RuneNode<Integer>> getChildRunes() {\n        return new ArrayList<>(children);\n    }\n}\n\nclass SpellCaster {\n    private final ExecutorService executor;\n    \n    public SpellCaster() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processCharmsSequentially(List<Charm> charms) {\n        for (Charm charm : charms) {\n            charm.invoke();\n        }\n    }\n    \n    public void processCharmsConcurrently(List<Charm> charms) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Charm charm : charms) {\n            futures.add(executor.submit(() -> charm.invoke()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> processRuneTreeSequentially(RuneNode<T> root) {\n        List<T> results = new ArrayList<>();\n        processRuneTreeSequentiallyRecursive(root, results);\n        return results;\n    }\n    \n    private <T> void processRuneTreeSequentiallyRecursive(RuneNode<T> node, List<T> results) {\n        if (node == null) {\n            return;\n        }\n        results.add(node.compute());\n        for (RuneNode<T> child : node.getChildRunes()) {\n            processRuneTreeSequentiallyRecursive(child, results);\n        }\n    }\n    \n    public <T> List<T> processRuneTreeConcurrently(RuneNode<T> root) {\n        ConcurrentLinkedQueue<T> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = new CountDownLatch(1);\n        processRuneTreeConcurrentlyRecursive(root, results, latch);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> void processRuneTreeConcurrentlyRecursive(RuneNode<T> node, ConcurrentLinkedQueue<T> results, CountDownLatch parentLatch) {\n        if (node == null) {\n            parentLatch.countDown();\n            return;\n        }\n        \n        executor.submit(() -> {\n            results.add(node.compute());\n            List<RuneNode<T>> children = node.getChildRunes();\n            if (children.isEmpty()) {\n                parentLatch.countDown();\n            } else {\n                CountDownLatch childLatch = new CountDownLatch(children.size());\n                for (RuneNode<T> child : children) {\n                    processRuneTreeConcurrentlyRecursive(child, results, childLatch);\n                }\n                try {\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                parentLatch.countDown();\n            }\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentSpellcasting {\n    public static void main(String[] args) {\n        SpellCaster caster = new SpellCaster();\n        \n        List<Charm> charms = Arrays.asList(\n            new SimpleCharm(\"Fire\"),\n            new SimpleCharm(\"Water\"),\n            new SimpleCharm(\"Earth\"),\n            new SimpleCharm(\"Air\")\n        );\n        \n        System.out.println(\"Sequential charm processing:\");\n        long startTime = System.currentTimeMillis();\n        caster.processCharmsSequentially(charms);\n        System.out.println(\"Sequential time: \" + (System.currentTimeMillis() - startTime) + \"ms\");\n        \n        System.out.println(\"\\nConcurrent charm processing:\");\n        startTime = System.currentTimeMillis();\n        caster.processCharmsConcurrently(charms);\n        System.out.println(\"Concurrent time: \" + (System.currentTimeMillis() - startTime) + \"ms\");\n        \n        RuneNode<Integer> root = new SimpleRuneNode(1, Arrays.asList(\n            new SimpleRuneNode(2, Arrays.asList(\n                new SimpleRuneNode(4, Collections.emptyList()),\n                new SimpleRuneNode(5, Collections.emptyList())\n            )),\n            new SimpleRuneNode(3, Arrays.asList(\n                new SimpleRuneNode(6, Collections.emptyList()),\n                new SimpleRuneNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        System.out.println(\"\\nSequential rune tree processing:\");\n        startTime = System.currentTimeMillis();\n        List<Integer> sequentialResults = caster.processRuneTreeSequentially(root);\n        System.out.println(\"Results: \" + sequentialResults);\n        System.out.println(\"Sequential time: \" + (System.currentTimeMillis() - startTime) + \"ms\");\n        \n        System.out.println(\"\\nConcurrent rune tree processing:\");\n        startTime = System.currentTimeMillis();\n        List<Integer> concurrentResults = caster.processRuneTreeConcurrently(root);\n        System.out.println(\"Results: \" + concurrentResults);\n        System.out.println(\"Concurrent time: \" + (System.currentTimeMillis() - startTime) + \"ms\");\n        \n        caster.shutdown();\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Waiting for results to be calculated in parallel. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write Java code that converts step-by-step summoning into simultaneous invocation using an Executor. The code should include two main processing methods: one that processes a list of talismans sequentially by iterating and activating each talisman in turn, and another that dispatches each talisman for parallel activation via an executor. Additionally, implement recursive versions of both sequential and parallel processing methods that traverse a forest of sigil-nodes, calculating results and collecting them in a thread-safe manner. The parallel version should properly utilize an ExecutorService to execute tasks concurrently, ensure all tasks complete before returning the final result collection, and use appropriate concurrency utilities for thread safety. Define interfaces Talisman and SigilNode, where SigilNode supports computation and retrieval of child sigils. Ensure the design follows good abstraction principles and includes proper generic typing. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\ninterface Talisman {\n    void activate();\n}\n\ninterface SigilNode<T> {\n    T compute();\n    List<SigilNode<T>> getChildren();\n}\n\nclass ConcreteTalisman implements Talisman {\n    private final String name;\n    \n    public ConcreteTalisman(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void activate() {\n        System.out.println(\"Activating talisman: \" + name);\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass ConcreteSigilNode<T> implements SigilNode<T> {\n    private final T value;\n    private final List<SigilNode<T>> children;\n    \n    public ConcreteSigilNode(T value, List<SigilNode<T>> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    @Override\n    public T compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<SigilNode<T>> getChildren() {\n        return children;\n    }\n}\n\nclass TalismanProcessor {\n    private final ExecutorService executor;\n    \n    public TalismanProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processSequential(List<Talisman> talismans) {\n        for (Talisman talisman : talismans) {\n            talisman.activate();\n        }\n    }\n    \n    public void processParallel(List<Talisman> talismans) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.activate()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> traverseSequential(SigilNode<T> root) {\n        List<T> results = new ArrayList<>();\n        traverseSequentialHelper(root, results);\n        return results;\n    }\n    \n    private <T> void traverseSequentialHelper(SigilNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode<T> child : node.getChildren()) {\n            traverseSequentialHelper(child, results);\n        }\n    }\n    \n    public <T> List<T> traverseParallel(SigilNode<T> root) {\n        ConcurrentLinkedQueue<T> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = new CountDownLatch(countNodes(root));\n        traverseParallelHelper(root, results, latch);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> void traverseParallelHelper(SigilNode<T> node, ConcurrentLinkedQueue<T> results, CountDownLatch latch) {\n        if (node == null) return;\n        executor.submit(() -> {\n            results.add(node.compute());\n            latch.countDown();\n        });\n        for (SigilNode<T> child : node.getChildren()) {\n            traverseParallelHelper(child, results, latch);\n        }\n    }\n    \n    private <T> int countNodes(SigilNode<T> node) {\n        if (node == null) return 0;\n        int count = 1;\n        for (SigilNode<T> child : node.getChildren()) {\n            count += countNodes(child);\n        }\n        return count;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProgram {\n    public static void main(String[] args) {\n        TalismanProcessor processor = new TalismanProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new ConcreteTalisman(\"Fire\"),\n            new ConcreteTalisman(\"Water\"),\n            new ConcreteTalisman(\"Earth\"),\n            new ConcreteTalisman(\"Air\")\n        );\n        \n        System.out.println(\"Sequential Talisman Processing:\");\n        processor.processSequential(talismans);\n        \n        System.out.println(\"\\nParallel Talisman Processing:\");\n        processor.processParallel(talismans);\n        \n        SigilNode<Integer> root = new ConcreteSigilNode<>(1,\n            Arrays.asList(\n                new ConcreteSigilNode<>(2,\n                    Arrays.asList(\n                        new ConcreteSigilNode<>(4, Collections.emptyList()),\n                        new ConcreteSigilNode<>(5, Collections.emptyList())\n                    )\n                ),\n                new ConcreteSigilNode<>(3,\n                    Arrays.asList(\n                        new ConcreteSigilNode<>(6, Collections.emptyList()),\n                        new ConcreteSigilNode<>(7, Collections.emptyList())\n                    )\n                )\n            )\n        );\n        \n        System.out.println(\"\\nSequential Sigil Traversal:\");\n        List<Integer> sequentialResults = processor.traverseSequential(root);\n        System.out.println(\"Results: \" + sequentialResults);\n        \n        System.out.println(\"\\nParallel Sigil Traversal:\");\n        List<Integer> parallelResults = processor.traverseParallel(root);\n        System.out.println(\"Results: \" + parallelResults);\n        \n        processor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\ninterface Talisman {\n    void activate();\n}\n\ninterface SigilNode<T> {\n    T compute();\n    List<SigilNode<T>> getChildren();\n}\n\nclass ConcreteTalisman implements Talisman {\n    private final String name;\n    \n    public ConcreteTalisman(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void activate() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass ConcreteSigilNode implements SigilNode<Integer> {\n    private final int value;\n    private final List<SigilNode<Integer>> children;\n    \n    public ConcreteSigilNode(int value, List<SigilNode<Integer>> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    @Override\n    public Integer compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<SigilNode<Integer>> getChildren() {\n        return children;\n    }\n}\n\nclass TalismanProcessor {\n    private final ExecutorService executor;\n    \n    public TalismanProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processSequential(List<Talisman> talismans) {\n        for (Talisman talisman : talismans) {\n            talisman.activate();\n        }\n    }\n    \n    public void processParallel(List<Talisman> talismans) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.activate()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> processSequentialRecursive(SigilNode<T> root) {\n        List<T> results = new ArrayList<>();\n        processSequentialRecursiveHelper(root, results);\n        return results;\n    }\n    \n    private <T> void processSequentialRecursiveHelper(SigilNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode<T> child : node.getChildren()) {\n            processSequentialRecursiveHelper(child, results);\n        }\n    }\n    \n    public <T> List<T> processParallelRecursive(SigilNode<T> root) {\n        List<T> results = new CopyOnWriteArrayList<>();\n        List<Future<?>> futures = new ArrayList<>();\n        processParallelRecursiveHelper(root, results, futures);\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> void processParallelRecursiveHelper(SigilNode<T> node, List<T> results, List<Future<?>> futures) {\n        if (node == null) return;\n        futures.add(executor.submit(() -> results.add(node.compute())));\n        for (SigilNode<T> child : node.getChildren()) {\n            processParallelRecursiveHelper(child, results, futures);\n        }\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProgram {\n    public static void main(String[] args) {\n        TalismanProcessor processor = new TalismanProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new ConcreteTalisman(\"Talisman1\"),\n            new ConcreteTalisman(\"Talisman2\"),\n            new ConcreteTalisman(\"Talisman3\")\n        );\n        \n        long startTime = System.currentTimeMillis();\n        processor.processSequential(talismans);\n        long sequentialTime = System.currentTimeMillis() - startTime;\n        \n        startTime = System.currentTimeMillis();\n        processor.processParallel(talismans);\n        long parallelTime = System.currentTimeMillis() - startTime;\n        \n        SigilNode<Integer> root = new ConcreteSigilNode(1, Arrays.asList(\n            new ConcreteSigilNode(2, Arrays.asList(\n                new ConcreteSigilNode(4, Collections.emptyList()),\n                new ConcreteSigilNode(5, Collections.emptyList())\n            )),\n            new ConcreteSigilNode(3, Arrays.asList(\n                new ConcreteSigilNode(6, Collections.emptyList()),\n                new ConcreteSigilNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        startTime = System.currentTimeMillis();\n        List<Integer> sequentialResults = processor.processSequentialRecursive(root);\n        long sequentialRecursiveTime = System.currentTimeMillis() - startTime;\n        \n        startTime = System.currentTimeMillis();\n        List<Integer> parallelResults = processor.processParallelRecursive(root);\n        long parallelRecursiveTime = System.currentTimeMillis() - startTime;\n        \n        System.out.println(\"Sequential Talisman Time: \" + sequentialTime + \"ms\");\n        System.out.println(\"Parallel Talisman Time: \" + parallelTime + \"ms\");\n        System.out.println(\"Sequential Recursive Results: \" + sequentialResults);\n        System.out.println(\"Sequential Recursive Time: \" + sequentialRecursiveTime + \"ms\");\n        System.out.println(\"Parallel Recursive Results: \" + parallelResults);\n        System.out.println(\"Parallel Recursive Time: \" + parallelRecursiveTime + \"ms\");\n        \n        processor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\ninterface Talisman {\n    void activate();\n}\n\ninterface SigilNode<T> {\n    T compute();\n    List<SigilNode<T>> getChildren();\n}\n\nclass ConcreteTalisman implements Talisman {\n    private final String name;\n    \n    public ConcreteTalisman(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void activate() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass ConcreteSigilNode implements SigilNode<Integer> {\n    private final int value;\n    private final List<SigilNode<Integer>> children;\n    \n    public ConcreteSigilNode(int value, List<SigilNode<Integer>> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    @Override\n    public Integer compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<SigilNode<Integer>> getChildren() {\n        return children;\n    }\n}\n\nclass TalismanProcessor {\n    private final ExecutorService executor;\n    \n    public TalismanProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processSequential(List<Talisman> talismans) {\n        for (Talisman talisman : talismans) {\n            talisman.activate();\n        }\n    }\n    \n    public void processParallel(List<Talisman> talismans) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.activate()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> processSequentialRecursive(SigilNode<T> root) {\n        List<T> results = new ArrayList<>();\n        processSequentialRecursiveHelper(root, results);\n        return results;\n    }\n    \n    private <T> void processSequentialRecursiveHelper(SigilNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode<T> child : node.getChildren()) {\n            processSequentialRecursiveHelper(child, results);\n        }\n    }\n    \n    public <T> List<T> processParallelRecursive(SigilNode<T> root) {\n        List<T> results = new CopyOnWriteArrayList<>();\n        CountDownLatch latch = processParallelRecursiveHelper(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> CountDownLatch processParallelRecursiveHelper(SigilNode<T> node, List<T> results) {\n        if (node == null) return new CountDownLatch(0);\n        \n        List<SigilNode<T>> children = node.getChildren();\n        int totalTasks = 1 + children.size();\n        CountDownLatch latch = new CountDownLatch(totalTasks);\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (SigilNode<T> child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = processParallelRecursiveHelper(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProgram {\n    public static void main(String[] args) {\n        TalismanProcessor processor = new TalismanProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new ConcreteTalisman(\"Fire\"),\n            new ConcreteTalisman(\"Water\"),\n            new ConcreteTalisman(\"Earth\"),\n            new ConcreteTalisman(\"Air\")\n        );\n        \n        long startTime = System.currentTimeMillis();\n        processor.processSequential(talismans);\n        long sequentialTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Sequential talisman processing time: \" + sequentialTime + \"ms\");\n        \n        startTime = System.currentTimeMillis();\n        processor.processParallel(talismans);\n        long parallelTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Parallel talisman processing time: \" + parallelTime + \"ms\");\n        \n        SigilNode<Integer> root = new ConcreteSigilNode(1, Arrays.asList(\n            new ConcreteSigilNode(2, Arrays.asList(\n                new ConcreteSigilNode(4, Collections.emptyList()),\n                new ConcreteSigilNode(5, Collections.emptyList())\n            )),\n            new ConcreteSigilNode(3, Arrays.asList(\n                new ConcreteSigilNode(6, Collections.emptyList()),\n                new ConcreteSigilNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        startTime = System.currentTimeMillis();\n        List<Integer> sequentialResults = processor.processSequentialRecursive(root);\n        long sequentialRecursiveTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Sequential recursive results: \" + sequentialResults);\n        System.out.println(\"Sequential recursive processing time: \" + sequentialRecursiveTime + \"ms\");\n        \n        startTime = System.currentTimeMillis();\n        List<Integer> parallelResults = processor.processParallelRecursive(root);\n        long parallelRecursiveTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Parallel recursive results: \" + parallelResults);\n        System.out.println(\"Parallel recursive processing time: \" + parallelRecursiveTime + \"ms\");\n        \n        processor.shutdown();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\npublic abstract class LLMC {\n\nvoid processSequentially(List<Element> elements) {\nfor (Element e : elements)\nprocess(e);\n}\n\nvoid processInParallel(Executor exec, List<Element> elements) {\nCountDownLatch latch = new CountDownLatch(elements.size());\nfor (final Element e : elements) {\nexec.execute(() -> {\nprocess(e);\nlatch.countDown();\n});\n}\ntry {\nlatch.await();\n} catch (InterruptedException ie) {\nThread.currentThread().interrupt();\n}\n}\n\npublic abstract void process(Element e);\n\npublic <T> void sequentialRecursive(List<Node<T>> nodes, Collection<T> results) {\nfor (Node<T> n : nodes) {\nresults.add(n.compute());\nsequentialRecursive(n.getChildren(), results);\n}\n}\n\npublic <T> Collection<T> parallelRecursive(List<Node<T>> nodes) throws InterruptedException {\nCollection<T> results = Collections.synchronizedList(new ArrayList<>());\nCountDownLatch latch = new CountDownLatch(nodes.size());\n\nThread worker = new Thread(() -> {\nfor (Node<T> n : nodes) {\nT result = n.compute();\nresults.add(result);\nsequentialRecursive(n.getChildren(), results);\nlatch.countDown();\n}\n});\n\nworker.start();\nlatch.await();\n\nreturn results;\n}\n\ninterface Element {}\ninterface Node<T> { T compute(); List<Node<T>> getChildren(); }\n\nstatic class MyElement implements Element {\nprivate final String name;\npublic MyElement(String name) { this.name = name; }\npublic String toString() { return \"Element: \" + name; }\n}\n\nstatic class MyNode implements Node<String> {\nprivate final String name;\nprivate final List<Node<String>> children;\npublic MyNode(String name, List<Node<String>> children) {\nthis.name = name;\nthis.children = children != null ? children : Collections.emptyList();\n}\npublic String compute() {\nreturn name;\n}\npublic List<Node<String>> getChildren() { return children; }\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC instance = new LLMC() {\npublic void process(Element e) {\n// Minimal processing\n}\n};\n\nList<Element> elements = Arrays.asList(new MyElement(\"A\"));\n\ninstance.processSequentially(elements);\n\nThread executor = new Thread(() -> {\ninstance.processInParallel(Runnable::run, elements);\n});\nexecutor.start();\nexecutor.join();\n\nNode<String> leaf = new MyNode(\"Leaf\", null);\nNode<String> root = new MyNode(\"Root\", Arrays.asList(leaf));\nList<Node<String>> tree = Arrays.asList(root);\n\nCollection<String> sequentialResults = new ArrayList<>();\ninstance.sequentialRecursive(tree, sequentialResults);\n\nCollection<String> parallelResults = instance.parallelRecursive(tree);\nSystem.out.println(parallelResults);\n}\n}",
        "max_depth": "5979",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.27%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 70.41%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.75%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=140274,visited=75778,backtracked=156262,end=925\nsearch:             maxDepth=59790,constraints=41100\nchoice generators:  thread=118930 (signal=0,lock=6,sharedRef=94033,threadApi=19,reschedule=13554), data=0\nheap:               new=25942,released=406373,maxLive=1105,gcCycles=216052\ninstructions:       26063592\nmax memory:         1011MB\nloaded code:        classes=151,methods=2720\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.69%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 57.39%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 59.14%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=139413,visited=62733,backtracked=142356,end=11494\nsearch:             maxDepth=59790,constraints=22800\nchoice generators:  thread=126541 (signal=0,lock=6,sharedRef=86368,threadApi=18,reschedule=26878), data=0\nheap:               new=45632,released=1152831,maxLive=1080,gcCycles=202139\ninstructions:       43380992\nmax memory:         1007MB\nloaded code:        classes=149,methods=2740\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.41%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 8.45%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 47.89%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=142,visited=0,backtracked=0,end=1\nsearch:             maxDepth=142,constraints=0\nchoice generators:  thread=142 (signal=0,lock=6,sharedRef=116,threadApi=13,reschedule=2), data=0\nheap:               new=1214,released=104,maxLive=1099,gcCycles=140\ninstructions:       20701\nmax memory:         981MB\nloaded code:        classes=146,methods=2720\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\""
        ],
        "codebleu_score": [
            64.56,
            63.22,
            62.77
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\ninterface Talisman {\n    void activate();\n}\n\ninterface SigilNode<T> {\n    T compute();\n    List<SigilNode<T>> getChildren();\n}\n\nclass ConcreteTalisman implements Talisman {\n    private final String name;\n    \n    public ConcreteTalisman(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void activate() {\n        System.out.println(\"Activating talisman: \" + name);\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass ConcreteSigilNode<T> implements SigilNode<T> {\n    private final T value;\n    private final List<SigilNode<T>> children;\n    \n    public ConcreteSigilNode(T value, List<SigilNode<T>> children) {\n        this.value = value;\n        this.children = new ArrayList<>(children);\n    }\n    \n    @Override\n    public T compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<SigilNode<T>> getChildren() {\n        return children;\n    }\n}\n\nclass TalismanProcessor {\n    private final ExecutorService executor;\n    \n    public TalismanProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processSequential(List<Talisman> talismans) {\n        for (Talisman talisman : talismans) {\n            talisman.activate();\n        }\n    }\n    \n    public void processParallel(List<Talisman> talismans) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.activate()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> traverseSequential(SigilNode<T> root) {\n        List<T> results = new ArrayList<>();\n        traverseSequentialHelper(root, results);\n        return results;\n    }\n    \n    private <T> void traverseSequentialHelper(SigilNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode<T> child : node.getChildren()) {\n            traverseSequentialHelper(child, results);\n        }\n    }\n    \n    public <T> List<T> traverseParallel(SigilNode<T> root) {\n        ConcurrentLinkedQueue<T> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = new CountDownLatch(countNodes(root));\n        traverseParallelHelper(root, results, latch);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> void traverseParallelHelper(SigilNode<T> node, ConcurrentLinkedQueue<T> results, CountDownLatch latch) {\n        if (node == null) return;\n        executor.submit(() -> {\n            results.add(node.compute());\n            latch.countDown();\n        });\n        for (SigilNode<T> child : node.getChildren()) {\n            traverseParallelHelper(child, results, latch);\n        }\n    }\n    \n    private <T> int countNodes(SigilNode<T> node) {\n        if (node == null) return 0;\n        int count = 1;\n        for (SigilNode<T> child : node.getChildren()) {\n            count += countNodes(child);\n        }\n        return count;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProgram {\n    public static void main(String[] args) {\n        TalismanProcessor processor = new TalismanProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new ConcreteTalisman(\"Fire\"),\n            new ConcreteTalisman(\"Water\"),\n            new ConcreteTalisman(\"Earth\"),\n            new ConcreteTalisman(\"Air\")\n        );\n        \n        System.out.println(\"Sequential Talisman Processing:\");\n        processor.processSequential(talismans);\n        \n        System.out.println(\"\\nParallel Talisman Processing:\");\n        processor.processParallel(talismans);\n        \n        SigilNode<Integer> root = new ConcreteSigilNode<>(1,\n            Arrays.asList(\n                new ConcreteSigilNode<>(2,\n                    Arrays.asList(\n                        new ConcreteSigilNode<>(4, Collections.emptyList()),\n                        new ConcreteSigilNode<>(5, Collections.emptyList())\n                    )\n                ),\n                new ConcreteSigilNode<>(3,\n                    Arrays.asList(\n                        new ConcreteSigilNode<>(6, Collections.emptyList()),\n                        new ConcreteSigilNode<>(7, Collections.emptyList())\n                    )\n                )\n            )\n        );\n        \n        System.out.println(\"\\nSequential Sigil Traversal:\");\n        List<Integer> sequentialResults = processor.traverseSequential(root);\n        System.out.println(\"Results: \" + sequentialResults);\n        \n        System.out.println(\"\\nParallel Sigil Traversal:\");\n        List<Integer> parallelResults = processor.traverseParallel(root);\n        System.out.println(\"Results: \" + parallelResults);\n        \n        processor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\ninterface Talisman {\n    void activate();\n}\n\ninterface SigilNode<T> {\n    T compute();\n    List<SigilNode<T>> getChildren();\n}\n\nclass ConcreteTalisman implements Talisman {\n    private final String name;\n    \n    public ConcreteTalisman(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void activate() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass ConcreteSigilNode implements SigilNode<Integer> {\n    private final int value;\n    private final List<SigilNode<Integer>> children;\n    \n    public ConcreteSigilNode(int value, List<SigilNode<Integer>> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    @Override\n    public Integer compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<SigilNode<Integer>> getChildren() {\n        return children;\n    }\n}\n\nclass TalismanProcessor {\n    private final ExecutorService executor;\n    \n    public TalismanProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processSequential(List<Talisman> talismans) {\n        for (Talisman talisman : talismans) {\n            talisman.activate();\n        }\n    }\n    \n    public void processParallel(List<Talisman> talismans) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.activate()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> processSequentialRecursive(SigilNode<T> root) {\n        List<T> results = new ArrayList<>();\n        processSequentialRecursiveHelper(root, results);\n        return results;\n    }\n    \n    private <T> void processSequentialRecursiveHelper(SigilNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode<T> child : node.getChildren()) {\n            processSequentialRecursiveHelper(child, results);\n        }\n    }\n    \n    public <T> List<T> processParallelRecursive(SigilNode<T> root) {\n        List<T> results = new CopyOnWriteArrayList<>();\n        List<Future<?>> futures = new ArrayList<>();\n        processParallelRecursiveHelper(root, results, futures);\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> void processParallelRecursiveHelper(SigilNode<T> node, List<T> results, List<Future<?>> futures) {\n        if (node == null) return;\n        futures.add(executor.submit(() -> results.add(node.compute())));\n        for (SigilNode<T> child : node.getChildren()) {\n            processParallelRecursiveHelper(child, results, futures);\n        }\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProgram {\n    public static void main(String[] args) {\n        TalismanProcessor processor = new TalismanProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new ConcreteTalisman(\"Talisman1\"),\n            new ConcreteTalisman(\"Talisman2\"),\n            new ConcreteTalisman(\"Talisman3\")\n        );\n        \n        long startTime = System.currentTimeMillis();\n        processor.processSequential(talismans);\n        long sequentialTime = System.currentTimeMillis() - startTime;\n        \n        startTime = System.currentTimeMillis();\n        processor.processParallel(talismans);\n        long parallelTime = System.currentTimeMillis() - startTime;\n        \n        SigilNode<Integer> root = new ConcreteSigilNode(1, Arrays.asList(\n            new ConcreteSigilNode(2, Arrays.asList(\n                new ConcreteSigilNode(4, Collections.emptyList()),\n                new ConcreteSigilNode(5, Collections.emptyList())\n            )),\n            new ConcreteSigilNode(3, Arrays.asList(\n                new ConcreteSigilNode(6, Collections.emptyList()),\n                new ConcreteSigilNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        startTime = System.currentTimeMillis();\n        List<Integer> sequentialResults = processor.processSequentialRecursive(root);\n        long sequentialRecursiveTime = System.currentTimeMillis() - startTime;\n        \n        startTime = System.currentTimeMillis();\n        List<Integer> parallelResults = processor.processParallelRecursive(root);\n        long parallelRecursiveTime = System.currentTimeMillis() - startTime;\n        \n        System.out.println(\"Sequential Talisman Time: \" + sequentialTime + \"ms\");\n        System.out.println(\"Parallel Talisman Time: \" + parallelTime + \"ms\");\n        System.out.println(\"Sequential Recursive Results: \" + sequentialResults);\n        System.out.println(\"Sequential Recursive Time: \" + sequentialRecursiveTime + \"ms\");\n        System.out.println(\"Parallel Recursive Results: \" + parallelResults);\n        System.out.println(\"Parallel Recursive Time: \" + parallelRecursiveTime + \"ms\");\n        \n        processor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\ninterface Talisman {\n    void activate();\n}\n\ninterface SigilNode<T> {\n    T compute();\n    List<SigilNode<T>> getChildren();\n}\n\nclass ConcreteTalisman implements Talisman {\n    private final String name;\n    \n    public ConcreteTalisman(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public void activate() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass ConcreteSigilNode implements SigilNode<Integer> {\n    private final int value;\n    private final List<SigilNode<Integer>> children;\n    \n    public ConcreteSigilNode(int value, List<SigilNode<Integer>> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    @Override\n    public Integer compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<SigilNode<Integer>> getChildren() {\n        return children;\n    }\n}\n\nclass TalismanProcessor {\n    private final ExecutorService executor;\n    \n    public TalismanProcessor() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processSequential(List<Talisman> talismans) {\n        for (Talisman talisman : talismans) {\n            talisman.activate();\n        }\n    }\n    \n    public void processParallel(List<Talisman> talismans) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Talisman talisman : talismans) {\n            futures.add(executor.submit(() -> talisman.activate()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public <T> List<T> processSequentialRecursive(SigilNode<T> root) {\n        List<T> results = new ArrayList<>();\n        processSequentialRecursiveHelper(root, results);\n        return results;\n    }\n    \n    private <T> void processSequentialRecursiveHelper(SigilNode<T> node, List<T> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (SigilNode<T> child : node.getChildren()) {\n            processSequentialRecursiveHelper(child, results);\n        }\n    }\n    \n    public <T> List<T> processParallelRecursive(SigilNode<T> root) {\n        List<T> results = new CopyOnWriteArrayList<>();\n        CountDownLatch latch = processParallelRecursiveHelper(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private <T> CountDownLatch processParallelRecursiveHelper(SigilNode<T> node, List<T> results) {\n        if (node == null) return new CountDownLatch(0);\n        \n        List<SigilNode<T>> children = node.getChildren();\n        int totalTasks = 1 + children.size();\n        CountDownLatch latch = new CountDownLatch(totalTasks);\n        \n        executor.submit(() -> {\n            try {\n                results.add(node.compute());\n            } finally {\n                latch.countDown();\n            }\n        });\n        \n        for (SigilNode<T> child : children) {\n            executor.submit(() -> {\n                try {\n                    CountDownLatch childLatch = processParallelRecursiveHelper(child, results);\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProgram {\n    public static void main(String[] args) {\n        TalismanProcessor processor = new TalismanProcessor();\n        \n        List<Talisman> talismans = Arrays.asList(\n            new ConcreteTalisman(\"Fire\"),\n            new ConcreteTalisman(\"Water\"),\n            new ConcreteTalisman(\"Earth\"),\n            new ConcreteTalisman(\"Air\")\n        );\n        \n        long startTime = System.currentTimeMillis();\n        processor.processSequential(talismans);\n        long sequentialTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Sequential talisman processing time: \" + sequentialTime + \"ms\");\n        \n        startTime = System.currentTimeMillis();\n        processor.processParallel(talismans);\n        long parallelTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Parallel talisman processing time: \" + parallelTime + \"ms\");\n        \n        SigilNode<Integer> root = new ConcreteSigilNode(1, Arrays.asList(\n            new ConcreteSigilNode(2, Arrays.asList(\n                new ConcreteSigilNode(4, Collections.emptyList()),\n                new ConcreteSigilNode(5, Collections.emptyList())\n            )),\n            new ConcreteSigilNode(3, Arrays.asList(\n                new ConcreteSigilNode(6, Collections.emptyList()),\n                new ConcreteSigilNode(7, Collections.emptyList())\n            ))\n        ));\n        \n        startTime = System.currentTimeMillis();\n        List<Integer> sequentialResults = processor.processSequentialRecursive(root);\n        long sequentialRecursiveTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Sequential recursive results: \" + sequentialResults);\n        System.out.println(\"Sequential recursive processing time: \" + sequentialRecursiveTime + \"ms\");\n        \n        startTime = System.currentTimeMillis();\n        List<Integer> parallelResults = processor.processParallelRecursive(root);\n        long parallelRecursiveTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Parallel recursive results: \" + parallelResults);\n        System.out.println(\"Parallel recursive processing time: \" + parallelRecursiveTime + \"ms\");\n        \n        processor.shutdown();\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Inducing a lock ordering to avoid deadlock. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that performs a thread-safe treasure transfer between two vaults while avoiding deadlock by inducing a consistent lock sequence. The program should use the vault object's identity hash code to determine the lock acquisition order. If both vaults have the same hash code, introduce a secondary tie-breaking lock to ensure consistent locking and prevent deadlock. Implement a helper class to carry out the actual transfer ritual, which checks for sufficient treasure before performing the debit and credit enchantments. Define interfaces for Vault and GoldAmount, and include an exception class for insufficient treasure scenarios. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GoldAmount {\n    long getAmount();\n}\n\ninterface Vault {\n    void debit(GoldAmount amount) throws InsufficientTreasureException;\n    void credit(GoldAmount amount);\n    GoldAmount getBalance();\n}\n\nclass InsufficientTreasureException extends Exception {\n    public InsufficientTreasureException(String message) {\n        super(message);\n    }\n}\n\nclass Gold implements GoldAmount {\n    private final long amount;\n    \n    public Gold(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass TreasureVault implements Vault {\n    private long balance;\n    private final String name;\n    \n    public TreasureVault(String name, long initialBalance) {\n        this.name = name;\n        this.balance = initialBalance;\n    }\n    \n    @Override\n    public void debit(GoldAmount amount) throws InsufficientTreasureException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientTreasureException(\"Insufficient treasure in vault \" + name);\n        }\n        balance -= amount.getAmount();\n    }\n    \n    @Override\n    public void credit(GoldAmount amount) {\n        balance += amount.getAmount();\n    }\n    \n    @Override\n    public GoldAmount getBalance() {\n        return new Gold(balance);\n    }\n    \n    public String getName() {\n        return name;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(Vault fromVault, Vault toVault, GoldAmount amount) \n            throws InsufficientTreasureException {\n        int fromHash = System.identityHashCode(fromVault);\n        int toHash = System.identityHashCode(toVault);\n        \n        if (fromHash < toHash) {\n            synchronized (fromVault) {\n                synchronized (toVault) {\n                    performTransfer(fromVault, toVault, amount);\n                }\n            }\n        } else if (fromHash > toHash) {\n            synchronized (toVault) {\n                synchronized (fromVault) {\n                    performTransfer(fromVault, toVault, amount);\n                }\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                synchronized (fromVault) {\n                    synchronized (toVault) {\n                        performTransfer(fromVault, toVault, amount);\n                    }\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(Vault fromVault, Vault toVault, GoldAmount amount) \n            throws InsufficientTreasureException {\n        fromVault.debit(amount);\n        toVault.credit(amount);\n    }\n}\n\npublic class TreasureTransfer {\n    public static void main(String[] args) {\n        TreasureVault vault1 = new TreasureVault(\"Dragon's Hoard\", 1000);\n        TreasureVault vault2 = new TreasureVault(\"King's Treasury\", 500);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    TransferHelper.transfer(vault1, vault2, new Gold(50));\n                    System.out.println(\"Thread 1: Transferred 50 gold from Dragon's Hoard to King's Treasury\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientTreasureException | InterruptedException e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    TransferHelper.transfer(vault2, vault1, new Gold(30));\n                    System.out.println(\"Thread 2: Transferred 30 gold from King's Treasury to Dragon's Hoard\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientTreasureException | InterruptedException e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Final Dragon's Hoard balance: \" + vault1.getBalance().getAmount());\n        System.out.println(\"Final King's Treasury balance: \" + vault2.getBalance().getAmount());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GoldAmount {\n    long getAmount();\n}\n\ninterface Vault {\n    void debit(GoldAmount amount) throws InsufficientTreasureException;\n    void credit(GoldAmount amount);\n    GoldAmount getBalance();\n}\n\nclass InsufficientTreasureException extends Exception {\n    public InsufficientTreasureException(String message) {\n        super(message);\n    }\n}\n\nclass Gold implements GoldAmount {\n    private final long amount;\n    \n    public Gold(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass TreasureVault implements Vault {\n    private long balance;\n    private final Lock lock = new ReentrantLock();\n    \n    public TreasureVault(long initialBalance) {\n        this.balance = initialBalance;\n    }\n    \n    @Override\n    public void debit(GoldAmount amount) throws InsufficientTreasureException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientTreasureException(\"Insufficient treasure in vault\");\n        }\n        balance -= amount.getAmount();\n    }\n    \n    @Override\n    public void credit(GoldAmount amount) {\n        balance += amount.getAmount();\n    }\n    \n    @Override\n    public GoldAmount getBalance() {\n        return new Gold(balance);\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(TreasureVault from, TreasureVault to, GoldAmount amount) \n            throws InsufficientTreasureException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        performTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(TreasureVault from, TreasureVault to, GoldAmount amount) \n            throws InsufficientTreasureException {\n        from.debit(amount);\n        to.credit(amount);\n    }\n}\n\npublic class TreasureTransfer {\n    public static void main(String[] args) {\n        TreasureVault vault1 = new TreasureVault(1000);\n        TreasureVault vault2 = new TreasureVault(500);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    TransferHelper.transfer(vault1, vault2, new Gold(50));\n                    System.out.println(\"Thread 1: Transferred 50 from vault1 to vault2\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientTreasureException | InterruptedException e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    TransferHelper.transfer(vault2, vault1, new Gold(30));\n                    System.out.println(\"Thread 2: Transferred 30 from vault2 to vault1\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientTreasureException | InterruptedException e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Final vault1 balance: \" + vault1.getBalance().getAmount());\n        System.out.println(\"Final vault2 balance: \" + vault2.getBalance().getAmount());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GoldAmount {\n    long getAmount();\n}\n\ninterface Vault {\n    void debit(GoldAmount amount) throws InsufficientTreasureException;\n    void credit(GoldAmount amount);\n    GoldAmount getBalance();\n    Lock getLock();\n}\n\nclass InsufficientTreasureException extends Exception {\n    public InsufficientTreasureException(String message) {\n        super(message);\n    }\n}\n\nclass GoldAmountImpl implements GoldAmount {\n    private final long amount;\n    \n    public GoldAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass VaultImpl implements Vault {\n    private long balance;\n    private final Lock lock = new ReentrantLock();\n    \n    public VaultImpl(long initialBalance) {\n        this.balance = initialBalance;\n    }\n    \n    @Override\n    public void debit(GoldAmount amount) throws InsufficientTreasureException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientTreasureException(\"Insufficient treasure in vault\");\n        }\n        balance -= amount.getAmount();\n    }\n    \n    @Override\n    public void credit(GoldAmount amount) {\n        balance += amount.getAmount();\n    }\n    \n    @Override\n    public GoldAmount getBalance() {\n        return new GoldAmountImpl(balance);\n    }\n    \n    @Override\n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TreasureTransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(Vault fromVault, Vault toVault, GoldAmount amount) \n            throws InsufficientTreasureException {\n        int fromHash = System.identityHashCode(fromVault);\n        int toHash = System.identityHashCode(toVault);\n        \n        if (fromHash < toHash) {\n            fromVault.getLock().lock();\n            try {\n                toVault.getLock().lock();\n                try {\n                    performTransfer(fromVault, toVault, amount);\n                } finally {\n                    toVault.getLock().unlock();\n                }\n            } finally {\n                fromVault.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            toVault.getLock().lock();\n            try {\n                fromVault.getLock().lock();\n                try {\n                    performTransfer(fromVault, toVault, amount);\n                } finally {\n                    fromVault.getLock().unlock();\n                }\n            } finally {\n                toVault.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                fromVault.getLock().lock();\n                try {\n                    toVault.getLock().lock();\n                    try {\n                        performTransfer(fromVault, toVault, amount);\n                    } finally {\n                        toVault.getLock().unlock();\n                    }\n                } finally {\n                    fromVault.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(Vault fromVault, Vault toVault, GoldAmount amount) \n            throws InsufficientTreasureException {\n        fromVault.debit(amount);\n        toVault.credit(amount);\n    }\n}\n\npublic class TreasureTransferProgram {\n    public static void main(String[] args) {\n        Vault vault1 = new VaultImpl(1000);\n        Vault vault2 = new VaultImpl(1000);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    TreasureTransferHelper.transfer(vault1, vault2, new GoldAmountImpl(50));\n                    System.out.println(\"Thread 1: Transferred 50 from vault1 to vault2\");\n                } catch (InsufficientTreasureException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    TreasureTransferHelper.transfer(vault2, vault1, new GoldAmountImpl(30));\n                    System.out.println(\"Thread 2: Transferred 30 from vault2 to vault1\");\n                } catch (InsufficientTreasureException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final vault1 balance: \" + vault1.getBalance().getAmount());\n        System.out.println(\"Final vault2 balance: \" + vault2.getBalance().getAmount());\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            true
        ],
        "ground_truth": "import java.math.BigDecimal;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class LLMC {\nprivate static final Object tieLock = new Object();\n\npublic void transferMoney(final Account fromAcct,\nfinal Account toAcct,\nfinal DollarAmount amount)\nthrows InsufficientFundsException {\nclass Helper {\npublic void transfer() throws InsufficientFundsException {\nif (fromAcct.getBalance().compareTo(amount) < 0)\nthrow new InsufficientFundsException();\nelse {\nfromAcct.debit(amount);\ntoAcct.credit(amount);\n}\n}\n}\n\nint fromHash = System.identityHashCode(fromAcct);\nint toHash = System.identityHashCode(toAcct);\n\nif (fromHash < toHash) {\nsynchronized (fromAcct) {\nsynchronized (toAcct) {\nnew Helper().transfer();\n}\n}\n} else if (fromHash > toHash) {\nsynchronized (toAcct) {\nsynchronized (fromAcct) {\nnew Helper().transfer();\n}\n}\n} else {\nsynchronized (tieLock) {\nsynchronized (fromAcct) {\nsynchronized (toAcct) {\nnew Helper().transfer();\n}\n}\n}\n}\n}\n\npublic static class DollarAmount implements Comparable<DollarAmount> {\nprivate final BigDecimal value;\n\npublic DollarAmount(BigDecimal value) {\nthis.value = value;\n}\n\npublic DollarAmount add(DollarAmount other) {\nreturn new DollarAmount(this.value.add(other.value));\n}\n\npublic DollarAmount subtract(DollarAmount other) {\nreturn new DollarAmount(this.value.subtract(other.value));\n}\n\n@Override\npublic int compareTo(DollarAmount other) {\nreturn this.value.compareTo(other.value);\n}\n\n@Override\npublic String toString() {\nreturn value.toString();\n}\n}\n\npublic interface Account {\nvoid debit(DollarAmount d);\n\nvoid credit(DollarAmount d);\n\nDollarAmount getBalance();\n\nint getAcctNo();\n}\n\npublic static class AccountImpl implements Account {\nprivate DollarAmount balance;\nprivate final int acctNo;\n\npublic AccountImpl(int acctNo, DollarAmount initialBalance) {\nthis.acctNo = acctNo;\nthis.balance = initialBalance;\n}\n\n@Override\npublic synchronized void debit(DollarAmount d) {\nbalance = balance.subtract(d);\n}\n\n@Override\npublic synchronized void credit(DollarAmount d) {\nbalance = balance.add(d);\n}\n\n@Override\npublic synchronized DollarAmount getBalance() {\nreturn balance;\n}\n\n@Override\npublic int getAcctNo() {\nreturn acctNo;\n}\n}\n\nstatic class InsufficientFundsException extends Exception {\npublic InsufficientFundsException() {\nsuper(\"Insufficient funds in account.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC service = new LLMC();\n\nAccount a1 = new AccountImpl(1, new DollarAmount(new BigDecimal(\"1000.00\")));\nAccount a2 = new AccountImpl(2, new DollarAmount(new BigDecimal(\"1000.00\")));\n\nRunnable task = () -> {\ntry {\n// Reduced iterations to 2 for faster completion\nfor (int i = 0; i < 2; i++) {\nservice.transferMoney(a1, a2, new DollarAmount(new BigDecimal(\"1.00\")));\nservice.transferMoney(a2, a1, new DollarAmount(new BigDecimal(\"1.00\")));\n}\n} catch (InsufficientFundsException e) {\ne.printStackTrace();\n}\n};\n\n// Reduced thread pool size to 2 to reduce thread overhead\nExecutorService executor = Executors.newFixedThreadPool(2);\n// Reduced number of tasks to 2\nfor (int i = 0; i < 2; i++) {\nexecutor.submit(task);\n}\n\nexecutor.shutdown();\nwhile (!executor.isTerminated()) {\nThread.sleep(10);\n}\n\nSystem.out.println(\"Final balance of Account 1: \" + ((AccountImpl) a1).getBalance());\nSystem.out.println(\"Final balance of Account 2: \" + ((AccountImpl) a2).getBalance());\n}\n}",
        "max_depth": "211",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.99%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TreasureVault@1cc.balance   main at...\"\n\n====================================================== statistics\nstates:             new=109053,visited=53826,backtracked=160770,end=0\nsearch:             maxDepth=2110,constraints=61190\nchoice generators:  thread=56396 (signal=0,lock=6615,sharedRef=33557,threadApi=2359,reschedule=82), data=0\nheap:               new=257142,released=126070,maxLive=754,gcCycles=162879\ninstructions:       12586125\nmax memory:         1005MB\nloaded code:        classes=141,methods=2424\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.12%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.13%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TreasureVault@1f9.balance   main at...\"\n\n====================================================== statistics\nstates:             new=99620,visited=38209,backtracked=135719,end=0\nsearch:             maxDepth=2110,constraints=59681\nchoice generators:  thread=48009 (signal=0,lock=440,sharedRef=30868,threadApi=1036,reschedule=59), data=0\nheap:               new=196352,released=99907,maxLive=756,gcCycles=137829\ninstructions:       11328978\nmax memory:         1000MB\nloaded code:        classes=139,methods=2406\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.12%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.17%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.08%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=145697,visited=122174,backtracked=265785,end=3\nsearch:             maxDepth=2110,constraints=61381\nchoice generators:  thread=93151 (signal=0,lock=781,sharedRef=71525,threadApi=2,reschedule=442), data=0\nheap:               new=654108,released=311174,maxLive=754,gcCycles=267871\ninstructions:       35939752\nmax memory:         1016MB\nloaded code:        classes=141,methods=2425\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TreasureVault@1cc.balance   main at...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field TreasureVault@1f9.balance   main at...\"",
            "no errors detected"
        ],
        "codebleu_score": [
            56.29,
            56.66,
            55.81
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GoldAmount {\n    long getAmount();\n}\n\ninterface Vault {\n    void debit(GoldAmount amount) throws InsufficientTreasureException;\n    void credit(GoldAmount amount);\n    GoldAmount getBalance();\n}\n\nclass InsufficientTreasureException extends Exception {\n    public InsufficientTreasureException(String message) {\n        super(message);\n    }\n}\n\nclass Gold implements GoldAmount {\n    private final long amount;\n    \n    public Gold(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass TreasureVault implements Vault {\n    private long balance;\n    private final String name;\n    \n    public TreasureVault(String name, long initialBalance) {\n        this.name = name;\n        this.balance = initialBalance;\n    }\n    \n    @Override\n    public void debit(GoldAmount amount) throws InsufficientTreasureException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientTreasureException(\"Insufficient treasure in vault \" + name);\n        }\n        balance -= amount.getAmount();\n    }\n    \n    @Override\n    public void credit(GoldAmount amount) {\n        balance += amount.getAmount();\n    }\n    \n    @Override\n    public GoldAmount getBalance() {\n        return new Gold(balance);\n    }\n    \n    public String getName() {\n        return name;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(Vault fromVault, Vault toVault, GoldAmount amount) \n            throws InsufficientTreasureException {\n        int fromHash = System.identityHashCode(fromVault);\n        int toHash = System.identityHashCode(toVault);\n        \n        if (fromHash < toHash) {\n            synchronized (fromVault) {\n                synchronized (toVault) {\n                    performTransfer(fromVault, toVault, amount);\n                }\n            }\n        } else if (fromHash > toHash) {\n            synchronized (toVault) {\n                synchronized (fromVault) {\n                    performTransfer(fromVault, toVault, amount);\n                }\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                synchronized (fromVault) {\n                    synchronized (toVault) {\n                        performTransfer(fromVault, toVault, amount);\n                    }\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(Vault fromVault, Vault toVault, GoldAmount amount) \n            throws InsufficientTreasureException {\n        fromVault.debit(amount);\n        toVault.credit(amount);\n    }\n}\n\npublic class TreasureTransfer {\n    public static void main(String[] args) {\n        TreasureVault vault1 = new TreasureVault(\"Dragon's Hoard\", 1000);\n        TreasureVault vault2 = new TreasureVault(\"King's Treasury\", 500);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    TransferHelper.transfer(vault1, vault2, new Gold(50));\n                    System.out.println(\"Thread 1: Transferred 50 gold from Dragon's Hoard to King's Treasury\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientTreasureException | InterruptedException e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    TransferHelper.transfer(vault2, vault1, new Gold(30));\n                    System.out.println(\"Thread 2: Transferred 30 gold from King's Treasury to Dragon's Hoard\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientTreasureException | InterruptedException e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Final Dragon's Hoard balance: \" + vault1.getBalance().getAmount());\n        System.out.println(\"Final King's Treasury balance: \" + vault2.getBalance().getAmount());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GoldAmount {\n    long getAmount();\n}\n\ninterface Vault {\n    void debit(GoldAmount amount) throws InsufficientTreasureException;\n    void credit(GoldAmount amount);\n    GoldAmount getBalance();\n}\n\nclass InsufficientTreasureException extends Exception {\n    public InsufficientTreasureException(String message) {\n        super(message);\n    }\n}\n\nclass Gold implements GoldAmount {\n    private final long amount;\n    \n    public Gold(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass TreasureVault implements Vault {\n    private long balance;\n    private final Lock lock = new ReentrantLock();\n    \n    public TreasureVault(long initialBalance) {\n        this.balance = initialBalance;\n    }\n    \n    @Override\n    public void debit(GoldAmount amount) throws InsufficientTreasureException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientTreasureException(\"Insufficient treasure in vault\");\n        }\n        balance -= amount.getAmount();\n    }\n    \n    @Override\n    public void credit(GoldAmount amount) {\n        balance += amount.getAmount();\n    }\n    \n    @Override\n    public GoldAmount getBalance() {\n        return new Gold(balance);\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(TreasureVault from, TreasureVault to, GoldAmount amount) \n            throws InsufficientTreasureException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        performTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(TreasureVault from, TreasureVault to, GoldAmount amount) \n            throws InsufficientTreasureException {\n        from.debit(amount);\n        to.credit(amount);\n    }\n}\n\npublic class TreasureTransfer {\n    public static void main(String[] args) {\n        TreasureVault vault1 = new TreasureVault(1000);\n        TreasureVault vault2 = new TreasureVault(500);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    TransferHelper.transfer(vault1, vault2, new Gold(50));\n                    System.out.println(\"Thread 1: Transferred 50 from vault1 to vault2\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientTreasureException | InterruptedException e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    TransferHelper.transfer(vault2, vault1, new Gold(30));\n                    System.out.println(\"Thread 2: Transferred 30 from vault2 to vault1\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientTreasureException | InterruptedException e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Final vault1 balance: \" + vault1.getBalance().getAmount());\n        System.out.println(\"Final vault2 balance: \" + vault2.getBalance().getAmount());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GoldAmount {\n    long getAmount();\n}\n\ninterface Vault {\n    void debit(GoldAmount amount) throws InsufficientTreasureException;\n    void credit(GoldAmount amount);\n    GoldAmount getBalance();\n    Lock getLock();\n}\n\nclass InsufficientTreasureException extends Exception {\n    public InsufficientTreasureException(String message) {\n        super(message);\n    }\n}\n\nclass GoldAmountImpl implements GoldAmount {\n    private final long amount;\n    \n    public GoldAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass VaultImpl implements Vault {\n    private long balance;\n    private final Lock lock = new ReentrantLock();\n    \n    public VaultImpl(long initialBalance) {\n        this.balance = initialBalance;\n    }\n    \n    @Override\n    public void debit(GoldAmount amount) throws InsufficientTreasureException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientTreasureException(\"Insufficient treasure in vault\");\n        }\n        balance -= amount.getAmount();\n    }\n    \n    @Override\n    public void credit(GoldAmount amount) {\n        balance += amount.getAmount();\n    }\n    \n    @Override\n    public GoldAmount getBalance() {\n        return new GoldAmountImpl(balance);\n    }\n    \n    @Override\n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TreasureTransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(Vault fromVault, Vault toVault, GoldAmount amount) \n            throws InsufficientTreasureException {\n        int fromHash = System.identityHashCode(fromVault);\n        int toHash = System.identityHashCode(toVault);\n        \n        if (fromHash < toHash) {\n            fromVault.getLock().lock();\n            try {\n                toVault.getLock().lock();\n                try {\n                    performTransfer(fromVault, toVault, amount);\n                } finally {\n                    toVault.getLock().unlock();\n                }\n            } finally {\n                fromVault.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            toVault.getLock().lock();\n            try {\n                fromVault.getLock().lock();\n                try {\n                    performTransfer(fromVault, toVault, amount);\n                } finally {\n                    fromVault.getLock().unlock();\n                }\n            } finally {\n                toVault.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                fromVault.getLock().lock();\n                try {\n                    toVault.getLock().lock();\n                    try {\n                        performTransfer(fromVault, toVault, amount);\n                    } finally {\n                        toVault.getLock().unlock();\n                    }\n                } finally {\n                    fromVault.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(Vault fromVault, Vault toVault, GoldAmount amount) \n            throws InsufficientTreasureException {\n        fromVault.debit(amount);\n        toVault.credit(amount);\n    }\n}\n\npublic class TreasureTransferProgram {\n    public static void main(String[] args) {\n        Vault vault1 = new VaultImpl(1000);\n        Vault vault2 = new VaultImpl(1000);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    TreasureTransferHelper.transfer(vault1, vault2, new GoldAmountImpl(50));\n                    System.out.println(\"Thread 1: Transferred 50 from vault1 to vault2\");\n                } catch (InsufficientTreasureException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    TreasureTransferHelper.transfer(vault2, vault1, new GoldAmountImpl(30));\n                    System.out.println(\"Thread 2: Transferred 30 from vault2 to vault1\");\n                } catch (InsufficientTreasureException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final vault1 balance: \" + vault1.getBalance().getAmount());\n        System.out.println(\"Final vault2 balance: \" + vault2.getBalance().getAmount());\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Inducing a lock ordering to avoid deadlock. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that executes a thread-safe gem transfer between two hoards while avoiding deadlock by enforcing a predictable lock order. The program should use the hoard object's identity hash code to determine the sequence of lock acquisition. If both hoards have the same hash code, introduce a secondary tie-breaking lock to guarantee consistent locking and prevent deadlock. Implement a helper class to carry out the actual transfer ritual, which verifies adequate gems before performing the withdrawal and deposit operations. Define interfaces for Hoard and GemAmount, and include an exception class for insufficient gems scenarios. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GemAmount {\n    int getAmount();\n}\n\ninterface Hoard {\n    void withdraw(GemAmount amount) throws InsufficientGemsException;\n    void deposit(GemAmount amount);\n    int getGemCount();\n    Lock getLock();\n}\n\nclass InsufficientGemsException extends Exception {\n    public InsufficientGemsException(String message) {\n        super(message);\n    }\n}\n\nclass GemAmountImpl implements GemAmount {\n    private final int amount;\n    \n    public GemAmountImpl(int amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass HoardImpl implements Hoard {\n    private int gemCount;\n    private final Lock lock = new ReentrantLock();\n    \n    public HoardImpl(int initialGems) {\n        this.gemCount = initialGems;\n    }\n    \n    @Override\n    public void withdraw(GemAmount amount) throws InsufficientGemsException {\n        if (gemCount < amount.getAmount()) {\n            throw new InsufficientGemsException(\"Insufficient gems in hoard\");\n        }\n        gemCount -= amount.getAmount();\n    }\n    \n    @Override\n    public void deposit(GemAmount amount) {\n        gemCount += amount.getAmount();\n    }\n    \n    @Override\n    public int getGemCount() {\n        return gemCount;\n    }\n    \n    @Override\n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(Hoard from, Hoard to, GemAmount amount) throws InsufficientGemsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        performTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(Hoard from, Hoard to, GemAmount amount) throws InsufficientGemsException {\n        from.withdraw(amount);\n        to.deposit(amount);\n    }\n}\n\npublic class GemTransferProgram {\n    public static void main(String[] args) {\n        HoardImpl hoard1 = new HoardImpl(1000);\n        HoardImpl hoard2 = new HoardImpl(1000);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transfer(hoard1, hoard2, new GemAmountImpl(5));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transfer(hoard2, hoard1, new GemAmountImpl(3));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Hoard 1 gems: \" + hoard1.getGemCount());\n        System.out.println(\"Hoard 2 gems: \" + hoard2.getGemCount());\n        System.out.println(\"Total gems: \" + (hoard1.getGemCount() + hoard2.getGemCount()));\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GemAmount {\n    int getAmount();\n}\n\ninterface Hoard {\n    void withdraw(GemAmount amount) throws InsufficientGemsException;\n    void deposit(GemAmount amount);\n    int getGemCount();\n}\n\nclass InsufficientGemsException extends Exception {\n    public InsufficientGemsException(String message) {\n        super(message);\n    }\n}\n\nclass GemAmountImpl implements GemAmount {\n    private final int amount;\n    \n    public GemAmountImpl(int amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass HoardImpl implements Hoard {\n    private int gemCount;\n    private final Lock lock = new ReentrantLock();\n    \n    public HoardImpl(int initialGems) {\n        this.gemCount = initialGems;\n    }\n    \n    @Override\n    public void withdraw(GemAmount amount) throws InsufficientGemsException {\n        if (gemCount < amount.getAmount()) {\n            throw new InsufficientGemsException(\"Not enough gems in hoard\");\n        }\n        gemCount -= amount.getAmount();\n    }\n    \n    @Override\n    public void deposit(GemAmount amount) {\n        gemCount += amount.getAmount();\n    }\n    \n    @Override\n    public int getGemCount() {\n        return gemCount;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transferGems(HoardImpl from, HoardImpl to, GemAmount amount) \n            throws InsufficientGemsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        performTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(HoardImpl from, HoardImpl to, GemAmount amount) \n            throws InsufficientGemsException {\n        from.withdraw(amount);\n        to.deposit(amount);\n    }\n}\n\npublic class GemTransferProgram {\n    public static void main(String[] args) {\n        HoardImpl hoard1 = new HoardImpl(1000);\n        HoardImpl hoard2 = new HoardImpl(1000);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transferGems(hoard1, hoard2, new GemAmountImpl(5));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    System.out.println(\"Transfer failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transferGems(hoard2, hoard1, new GemAmountImpl(3));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    System.out.println(\"Transfer failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Hoard 1 final gem count: \" + hoard1.getGemCount());\n        System.out.println(\"Hoard 2 final gem count: \" + hoard2.getGemCount());\n        System.out.println(\"Total gems: \" + (hoard1.getGemCount() + hoard2.getGemCount()));\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GemAmount {\n    int getValue();\n}\n\ninterface Hoard {\n    void withdraw(GemAmount amount) throws InsufficientGemsException;\n    void deposit(GemAmount amount);\n    int getGemCount();\n}\n\nclass InsufficientGemsException extends Exception {\n    public InsufficientGemsException(String message) {\n        super(message);\n    }\n}\n\nclass GemAmountImpl implements GemAmount {\n    private final int value;\n    \n    public GemAmountImpl(int value) {\n        this.value = value;\n    }\n    \n    @Override\n    public int getValue() {\n        return value;\n    }\n}\n\nclass HoardImpl implements Hoard {\n    private int gemCount;\n    private final Lock lock = new ReentrantLock();\n    \n    public HoardImpl(int initialGems) {\n        this.gemCount = initialGems;\n    }\n    \n    @Override\n    public void withdraw(GemAmount amount) throws InsufficientGemsException {\n        if (gemCount < amount.getValue()) {\n            throw new InsufficientGemsException(\"Insufficient gems in hoard\");\n        }\n        gemCount -= amount.getValue();\n    }\n    \n    @Override\n    public void deposit(GemAmount amount) {\n        gemCount += amount.getValue();\n    }\n    \n    @Override\n    public int getGemCount() {\n        return gemCount;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(HoardImpl from, HoardImpl to, GemAmount amount) throws InsufficientGemsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        performTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(HoardImpl from, HoardImpl to, GemAmount amount) throws InsufficientGemsException {\n        from.withdraw(amount);\n        to.deposit(amount);\n    }\n}\n\npublic class GemTransfer {\n    public static void main(String[] args) {\n        HoardImpl hoard1 = new HoardImpl(1000);\n        HoardImpl hoard2 = new HoardImpl(1000);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transfer(hoard1, hoard2, new GemAmountImpl(5));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    System.out.println(\"Transfer failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transfer(hoard2, hoard1, new GemAmountImpl(3));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    System.out.println(\"Transfer failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Hoard 1 final gems: \" + hoard1.getGemCount());\n        System.out.println(\"Hoard 2 final gems: \" + hoard2.getGemCount());\n        System.out.println(\"Total gems: \" + (hoard1.getGemCount() + hoard2.getGemCount()));\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.math.BigDecimal;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class LLMC {\nprivate static final Object tieLock = new Object();\n\npublic void transferMoney(final Account fromAcct,\nfinal Account toAcct,\nfinal DollarAmount amount)\nthrows InsufficientFundsException {\nclass Helper {\npublic void transfer() throws InsufficientFundsException {\nif (fromAcct.getBalance().compareTo(amount) < 0)\nthrow new InsufficientFundsException();\nelse {\nfromAcct.debit(amount);\ntoAcct.credit(amount);\n}\n}\n}\n\nint fromHash = System.identityHashCode(fromAcct);\nint toHash = System.identityHashCode(toAcct);\n\nif (fromHash < toHash) {\nsynchronized (fromAcct) {\nsynchronized (toAcct) {\nnew Helper().transfer();\n}\n}\n} else if (fromHash > toHash) {\nsynchronized (toAcct) {\nsynchronized (fromAcct) {\nnew Helper().transfer();\n}\n}\n} else {\nsynchronized (tieLock) {\nsynchronized (fromAcct) {\nsynchronized (toAcct) {\nnew Helper().transfer();\n}\n}\n}\n}\n}\n\npublic static class DollarAmount implements Comparable<DollarAmount> {\nprivate final BigDecimal value;\n\npublic DollarAmount(BigDecimal value) {\nthis.value = value;\n}\n\npublic DollarAmount add(DollarAmount other) {\nreturn new DollarAmount(this.value.add(other.value));\n}\n\npublic DollarAmount subtract(DollarAmount other) {\nreturn new DollarAmount(this.value.subtract(other.value));\n}\n\n@Override\npublic int compareTo(DollarAmount other) {\nreturn this.value.compareTo(other.value);\n}\n\n@Override\npublic String toString() {\nreturn value.toString();\n}\n}\n\npublic interface Account {\nvoid debit(DollarAmount d);\n\nvoid credit(DollarAmount d);\n\nDollarAmount getBalance();\n\nint getAcctNo();\n}\n\npublic static class AccountImpl implements Account {\nprivate DollarAmount balance;\nprivate final int acctNo;\n\npublic AccountImpl(int acctNo, DollarAmount initialBalance) {\nthis.acctNo = acctNo;\nthis.balance = initialBalance;\n}\n\n@Override\npublic synchronized void debit(DollarAmount d) {\nbalance = balance.subtract(d);\n}\n\n@Override\npublic synchronized void credit(DollarAmount d) {\nbalance = balance.add(d);\n}\n\n@Override\npublic synchronized DollarAmount getBalance() {\nreturn balance;\n}\n\n@Override\npublic int getAcctNo() {\nreturn acctNo;\n}\n}\n\nstatic class InsufficientFundsException extends Exception {\npublic InsufficientFundsException() {\nsuper(\"Insufficient funds in account.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC service = new LLMC();\n\nAccount a1 = new AccountImpl(1, new DollarAmount(new BigDecimal(\"1000.00\")));\nAccount a2 = new AccountImpl(2, new DollarAmount(new BigDecimal(\"1000.00\")));\n\nRunnable task = () -> {\ntry {\n// Reduced iterations to 2 for faster completion\nfor (int i = 0; i < 2; i++) {\nservice.transferMoney(a1, a2, new DollarAmount(new BigDecimal(\"1.00\")));\nservice.transferMoney(a2, a1, new DollarAmount(new BigDecimal(\"1.00\")));\n}\n} catch (InsufficientFundsException e) {\ne.printStackTrace();\n}\n};\n\n// Reduced thread pool size to 2 to reduce thread overhead\nExecutorService executor = Executors.newFixedThreadPool(2);\n// Reduced number of tasks to 2\nfor (int i = 0; i < 2; i++) {\nexecutor.submit(task);\n}\n\nexecutor.shutdown();\nwhile (!executor.isTerminated()) {\nThread.sleep(10);\n}\n\nSystem.out.println(\"Final balance of Account 1: \" + ((AccountImpl) a1).getBalance());\nSystem.out.println(\"Final balance of Account 2: \" + ((AccountImpl) a2).getBalance());\n}\n}",
        "max_depth": "211",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.13%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.15%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field HoardImpl@1f9.gemCount   main at Ho...\"\n\n====================================================== statistics\nstates:             new=100835,visited=38344,backtracked=137069,end=0\nsearch:             maxDepth=2110,constraints=60558\nchoice generators:  thread=48464 (signal=0,lock=441,sharedRef=31130,threadApi=1037,reschedule=66), data=0\nheap:               new=161595,released=86873,maxLive=753,gcCycles=139179\ninstructions:       11312734\nmax memory:         1001MB\nloaded code:        classes=139,methods=2407\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.13%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.14%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field HoardImpl@1f9.gemCount   main at Ho...\"\n\n====================================================== statistics\nstates:             new=100875,visited=38347,backtracked=137112,end=0\nsearch:             maxDepth=2110,constraints=60583\nchoice generators:  thread=48480 (signal=0,lock=442,sharedRef=31138,threadApi=1037,reschedule=66), data=0\nheap:               new=181327,released=106581,maxLive=753,gcCycles=139222\ninstructions:       11311035\nmax memory:         1001MB\nloaded code:        classes=139,methods=2406\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.74%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.75%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field HoardImpl@1f9.gemCount   main at Ho...\"\n\n====================================================== statistics\nstates:             new=181996,visited=50091,backtracked=229977,end=0\nsearch:             maxDepth=2110,constraints=118055\nchoice generators:  thread=79441 (signal=0,lock=700,sharedRef=49995,threadApi=1041,reschedule=68), data=0\nheap:               new=194502,released=105686,maxLive=753,gcCycles=232087\ninstructions:       14421311\nmax memory:         1011MB\nloaded code:        classes=139,methods=2406\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field HoardImpl@1f9.gemCount   main at Ho...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field HoardImpl@1f9.gemCount   main at Ho...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field HoardImpl@1f9.gemCount   main at Ho...\""
        ],
        "codebleu_score": [
            56.66,
            56.53,
            56.05
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GemAmount {\n    int getAmount();\n}\n\ninterface Hoard {\n    void withdraw(GemAmount amount) throws InsufficientGemsException;\n    void deposit(GemAmount amount);\n    int getGemCount();\n    Lock getLock();\n}\n\nclass InsufficientGemsException extends Exception {\n    public InsufficientGemsException(String message) {\n        super(message);\n    }\n}\n\nclass GemAmountImpl implements GemAmount {\n    private final int amount;\n    \n    public GemAmountImpl(int amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass HoardImpl implements Hoard {\n    private int gemCount;\n    private final Lock lock = new ReentrantLock();\n    \n    public HoardImpl(int initialGems) {\n        this.gemCount = initialGems;\n    }\n    \n    @Override\n    public void withdraw(GemAmount amount) throws InsufficientGemsException {\n        if (gemCount < amount.getAmount()) {\n            throw new InsufficientGemsException(\"Insufficient gems in hoard\");\n        }\n        gemCount -= amount.getAmount();\n    }\n    \n    @Override\n    public void deposit(GemAmount amount) {\n        gemCount += amount.getAmount();\n    }\n    \n    @Override\n    public int getGemCount() {\n        return gemCount;\n    }\n    \n    @Override\n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(Hoard from, Hoard to, GemAmount amount) throws InsufficientGemsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        performTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(Hoard from, Hoard to, GemAmount amount) throws InsufficientGemsException {\n        from.withdraw(amount);\n        to.deposit(amount);\n    }\n}\n\npublic class GemTransferProgram {\n    public static void main(String[] args) {\n        HoardImpl hoard1 = new HoardImpl(1000);\n        HoardImpl hoard2 = new HoardImpl(1000);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transfer(hoard1, hoard2, new GemAmountImpl(5));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transfer(hoard2, hoard1, new GemAmountImpl(3));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Hoard 1 gems: \" + hoard1.getGemCount());\n        System.out.println(\"Hoard 2 gems: \" + hoard2.getGemCount());\n        System.out.println(\"Total gems: \" + (hoard1.getGemCount() + hoard2.getGemCount()));\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GemAmount {\n    int getAmount();\n}\n\ninterface Hoard {\n    void withdraw(GemAmount amount) throws InsufficientGemsException;\n    void deposit(GemAmount amount);\n    int getGemCount();\n}\n\nclass InsufficientGemsException extends Exception {\n    public InsufficientGemsException(String message) {\n        super(message);\n    }\n}\n\nclass GemAmountImpl implements GemAmount {\n    private final int amount;\n    \n    public GemAmountImpl(int amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass HoardImpl implements Hoard {\n    private int gemCount;\n    private final Lock lock = new ReentrantLock();\n    \n    public HoardImpl(int initialGems) {\n        this.gemCount = initialGems;\n    }\n    \n    @Override\n    public void withdraw(GemAmount amount) throws InsufficientGemsException {\n        if (gemCount < amount.getAmount()) {\n            throw new InsufficientGemsException(\"Not enough gems in hoard\");\n        }\n        gemCount -= amount.getAmount();\n    }\n    \n    @Override\n    public void deposit(GemAmount amount) {\n        gemCount += amount.getAmount();\n    }\n    \n    @Override\n    public int getGemCount() {\n        return gemCount;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transferGems(HoardImpl from, HoardImpl to, GemAmount amount) \n            throws InsufficientGemsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        performTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(HoardImpl from, HoardImpl to, GemAmount amount) \n            throws InsufficientGemsException {\n        from.withdraw(amount);\n        to.deposit(amount);\n    }\n}\n\npublic class GemTransferProgram {\n    public static void main(String[] args) {\n        HoardImpl hoard1 = new HoardImpl(1000);\n        HoardImpl hoard2 = new HoardImpl(1000);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transferGems(hoard1, hoard2, new GemAmountImpl(5));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    System.out.println(\"Transfer failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transferGems(hoard2, hoard1, new GemAmountImpl(3));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    System.out.println(\"Transfer failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Hoard 1 final gem count: \" + hoard1.getGemCount());\n        System.out.println(\"Hoard 2 final gem count: \" + hoard2.getGemCount());\n        System.out.println(\"Total gems: \" + (hoard1.getGemCount() + hoard2.getGemCount()));\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface GemAmount {\n    int getValue();\n}\n\ninterface Hoard {\n    void withdraw(GemAmount amount) throws InsufficientGemsException;\n    void deposit(GemAmount amount);\n    int getGemCount();\n}\n\nclass InsufficientGemsException extends Exception {\n    public InsufficientGemsException(String message) {\n        super(message);\n    }\n}\n\nclass GemAmountImpl implements GemAmount {\n    private final int value;\n    \n    public GemAmountImpl(int value) {\n        this.value = value;\n    }\n    \n    @Override\n    public int getValue() {\n        return value;\n    }\n}\n\nclass HoardImpl implements Hoard {\n    private int gemCount;\n    private final Lock lock = new ReentrantLock();\n    \n    public HoardImpl(int initialGems) {\n        this.gemCount = initialGems;\n    }\n    \n    @Override\n    public void withdraw(GemAmount amount) throws InsufficientGemsException {\n        if (gemCount < amount.getValue()) {\n            throw new InsufficientGemsException(\"Insufficient gems in hoard\");\n        }\n        gemCount -= amount.getValue();\n    }\n    \n    @Override\n    public void deposit(GemAmount amount) {\n        gemCount += amount.getValue();\n    }\n    \n    @Override\n    public int getGemCount() {\n        return gemCount;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieBreakerLock = new ReentrantLock();\n    \n    public static void transfer(HoardImpl from, HoardImpl to, GemAmount amount) throws InsufficientGemsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    performTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        performTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void performTransfer(HoardImpl from, HoardImpl to, GemAmount amount) throws InsufficientGemsException {\n        from.withdraw(amount);\n        to.deposit(amount);\n    }\n}\n\npublic class GemTransfer {\n    public static void main(String[] args) {\n        HoardImpl hoard1 = new HoardImpl(1000);\n        HoardImpl hoard2 = new HoardImpl(1000);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transfer(hoard1, hoard2, new GemAmountImpl(5));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    System.out.println(\"Transfer failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                try {\n                    TransferHelper.transfer(hoard2, hoard1, new GemAmountImpl(3));\n                    Thread.sleep(10);\n                } catch (InsufficientGemsException | InterruptedException e) {\n                    System.out.println(\"Transfer failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Hoard 1 final gems: \" + hoard1.getGemCount());\n        System.out.println(\"Hoard 2 final gems: \" + hoard2.getGemCount());\n        System.out.println(\"Total gems: \" + (hoard1.getGemCount() + hoard2.getGemCount()));\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Inducing a lock ordering to avoid deadlock. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that conducts a thread-safe crystal transfer between two vaulting nodes while avoiding deadlock by maintaining a stable lock hierarchy. The program should use the vaulting node's identity hash code to determine the order of lock acquisition. If both nodes share the same hash code, introduce a secondary tie-breaking lock to ensure consistent locking and prevent deadlock. Implement a helper class to carry out the actual transfer rite, which verifies sufficient crystals before performing the withdrawal and deposit enchantments. Define interfaces for VaultNode and CrystalAmount, and include an exception class for insufficient crystals scenarios. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface CrystalAmount {\n    long getValue();\n}\n\ninterface VaultNode {\n    long getCrystals();\n    void setCrystals(long crystals);\n    ReentrantLock getLock();\n}\n\nclass InsufficientCrystalsException extends Exception {\n    public InsufficientCrystalsException(String message) {\n        super(message);\n    }\n}\n\nclass SimpleCrystalAmount implements CrystalAmount {\n    private final long value;\n    \n    public SimpleCrystalAmount(long value) {\n        this.value = value;\n    }\n    \n    public long getValue() {\n        return value;\n    }\n}\n\nclass SimpleVaultNode implements VaultNode {\n    private long crystals;\n    private final ReentrantLock lock;\n    \n    public SimpleVaultNode(long initialCrystals) {\n        this.crystals = initialCrystals;\n        this.lock = new ReentrantLock();\n    }\n    \n    public long getCrystals() {\n        return crystals;\n    }\n    \n    public void setCrystals(long crystals) {\n        this.crystals = crystals;\n    }\n    \n    public ReentrantLock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final ReentrantLock tieBreakerLock = new ReentrantLock();\n    \n    public static void performTransfer(VaultNode from, VaultNode to, CrystalAmount amount) throws InsufficientCrystalsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    executeTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    executeTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        executeTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void executeTransfer(VaultNode from, VaultNode to, CrystalAmount amount) throws InsufficientCrystalsException {\n        long transferAmount = amount.getValue();\n        if (from.getCrystals() < transferAmount) {\n            throw new InsufficientCrystalsException(\"Insufficient crystals for transfer\");\n        }\n        from.setCrystals(from.getCrystals() - transferAmount);\n        to.setCrystals(to.getCrystals() + transferAmount);\n    }\n}\n\npublic class CrystalTransfer {\n    public static void main(String[] args) {\n        VaultNode vault1 = new SimpleVaultNode(1000);\n        VaultNode vault2 = new SimpleVaultNode(500);\n        VaultNode vault3 = new SimpleVaultNode(200);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                TransferHelper.performTransfer(vault1, vault2, new SimpleCrystalAmount(100));\n                System.out.println(\"Transfer 1 completed\");\n            } catch (InsufficientCrystalsException e) {\n                System.out.println(\"Transfer 1 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                TransferHelper.performTransfer(vault2, vault3, new SimpleCrystalAmount(50));\n                System.out.println(\"Transfer 2 completed\");\n            } catch (InsufficientCrystalsException e) {\n                System.out.println(\"Transfer 2 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Vault 1: \" + vault1.getCrystals());\n        System.out.println(\"Vault 2: \" + vault2.getCrystals());\n        System.out.println(\"Vault 3: \" + vault3.getCrystals());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface CrystalAmount {\n    long getAmount();\n}\n\ninterface VaultNode {\n    void withdraw(CrystalAmount amount) throws InsufficientCrystalsException;\n    void deposit(CrystalAmount amount);\n    long getCrystalBalance();\n}\n\nclass InsufficientCrystalsException extends Exception {\n    public InsufficientCrystalsException(String message) {\n        super(message);\n    }\n}\n\nclass CrystalAmountImpl implements CrystalAmount {\n    private final long amount;\n    \n    public CrystalAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass VaultNodeImpl implements VaultNode {\n    private long crystalBalance;\n    private final ReentrantLock lock = new ReentrantLock();\n    \n    public VaultNodeImpl(long initialBalance) {\n        this.crystalBalance = initialBalance;\n    }\n    \n    @Override\n    public void withdraw(CrystalAmount amount) throws InsufficientCrystalsException {\n        if (crystalBalance < amount.getAmount()) {\n            throw new InsufficientCrystalsException(\"Insufficient crystals for withdrawal\");\n        }\n        crystalBalance -= amount.getAmount();\n    }\n    \n    @Override\n    public void deposit(CrystalAmount amount) {\n        crystalBalance += amount.getAmount();\n    }\n    \n    @Override\n    public long getCrystalBalance() {\n        return crystalBalance;\n    }\n    \n    public ReentrantLock getLock() {\n        return lock;\n    }\n}\n\nclass CrystalTransferHelper {\n    private static final ReentrantLock tieBreakerLock = new ReentrantLock();\n    \n    public static void performTransfer(VaultNodeImpl source, VaultNodeImpl destination, CrystalAmount amount) \n            throws InsufficientCrystalsException {\n        int sourceHash = System.identityHashCode(source);\n        int destHash = System.identityHashCode(destination);\n        \n        if (sourceHash < destHash) {\n            source.getLock().lock();\n            try {\n                destination.getLock().lock();\n                try {\n                    executeTransfer(source, destination, amount);\n                } finally {\n                    destination.getLock().unlock();\n                }\n            } finally {\n                source.getLock().unlock();\n            }\n        } else if (sourceHash > destHash) {\n            destination.getLock().lock();\n            try {\n                source.getLock().lock();\n                try {\n                    executeTransfer(source, destination, amount);\n                } finally {\n                    source.getLock().unlock();\n                }\n            } finally {\n                destination.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                source.getLock().lock();\n                try {\n                    destination.getLock().lock();\n                    try {\n                        executeTransfer(source, destination, amount);\n                    } finally {\n                        destination.getLock().unlock();\n                    }\n                } finally {\n                    source.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void executeTransfer(VaultNodeImpl source, VaultNodeImpl destination, CrystalAmount amount) \n            throws InsufficientCrystalsException {\n        source.withdraw(amount);\n        destination.deposit(amount);\n    }\n}\n\npublic class CrystalTransferProgram {\n    public static void main(String[] args) {\n        VaultNodeImpl vault1 = new VaultNodeImpl(1000);\n        VaultNodeImpl vault2 = new VaultNodeImpl(500);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                CrystalAmount amount = new CrystalAmountImpl(100);\n                CrystalTransferHelper.performTransfer(vault1, vault2, amount);\n                System.out.println(\"Transfer 1 completed: Vault1=\" + vault1.getCrystalBalance() + \n                                 \", Vault2=\" + vault2.getCrystalBalance());\n            } catch (InsufficientCrystalsException e) {\n                System.out.println(\"Transfer 1 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                CrystalAmount amount = new CrystalAmountImpl(50);\n                CrystalTransferHelper.performTransfer(vault2, vault1, amount);\n                System.out.println(\"Transfer 2 completed: Vault1=\" + vault1.getCrystalBalance() + \n                                 \", Vault2=\" + vault2.getCrystalBalance());\n            } catch (InsufficientCrystalsException e) {\n                System.out.println(\"Transfer 2 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final balances: Vault1=\" + vault1.getCrystalBalance() + \n                         \", Vault2=\" + vault2.getCrystalBalance());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface CrystalAmount {\n    long getAmount();\n}\n\ninterface VaultNode {\n    long getCrystals();\n    void setCrystals(long crystals);\n    ReentrantLock getLock();\n}\n\nclass InsufficientCrystalsException extends Exception {\n    public InsufficientCrystalsException(String message) {\n        super(message);\n    }\n}\n\nclass CrystalAmountImpl implements CrystalAmount {\n    private final long amount;\n    \n    public CrystalAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass VaultNodeImpl implements VaultNode {\n    private long crystals;\n    private final ReentrantLock lock = new ReentrantLock();\n    \n    public VaultNodeImpl(long initialCrystals) {\n        this.crystals = initialCrystals;\n    }\n    \n    @Override\n    public long getCrystals() {\n        return crystals;\n    }\n    \n    @Override\n    public void setCrystals(long crystals) {\n        this.crystals = crystals;\n    }\n    \n    @Override\n    public ReentrantLock getLock() {\n        return lock;\n    }\n}\n\nclass TransferRite {\n    private static final ReentrantLock tieBreakerLock = new ReentrantLock();\n    \n    public void performTransfer(VaultNode from, VaultNode to, CrystalAmount amount) throws InsufficientCrystalsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    executeTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    executeTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        executeTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private void executeTransfer(VaultNode from, VaultNode to, CrystalAmount amount) throws InsufficientCrystalsException {\n        if (from.getCrystals() < amount.getAmount()) {\n            throw new InsufficientCrystalsException(\"Insufficient crystals in source vault\");\n        }\n        from.setCrystals(from.getCrystals() - amount.getAmount());\n        to.setCrystals(to.getCrystals() + amount.getAmount());\n    }\n}\n\npublic class CrystalTransferProgram {\n    public static void main(String[] args) {\n        VaultNode vault1 = new VaultNodeImpl(1000);\n        VaultNode vault2 = new VaultNodeImpl(500);\n        VaultNode vault3 = new VaultNodeImpl(200);\n        \n        TransferRite transferRite = new TransferRite();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    transferRite.performTransfer(vault1, vault2, new CrystalAmountImpl(50));\n                    System.out.println(\"Thread 1: Transferred 50 crystals from vault1 to vault2\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientCrystalsException | InterruptedException e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    transferRite.performTransfer(vault2, vault3, new CrystalAmountImpl(30));\n                    System.out.println(\"Thread 2: Transferred 30 crystals from vault2 to vault3\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientCrystalsException | InterruptedException e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"Final vault1 crystals: \" + vault1.getCrystals());\n        System.out.println(\"Final vault2 crystals: \" + vault2.getCrystals());\n        System.out.println(\"Final vault3 crystals: \" + vault3.getCrystals());\n    }\n}"
        ],
        "graded_list": [
            true,
            false,
            true
        ],
        "ground_truth": "import java.math.BigDecimal;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class LLMC {\nprivate static final Object tieLock = new Object();\n\npublic void transferMoney(final Account fromAcct,\nfinal Account toAcct,\nfinal DollarAmount amount)\nthrows InsufficientFundsException {\nclass Helper {\npublic void transfer() throws InsufficientFundsException {\nif (fromAcct.getBalance().compareTo(amount) < 0)\nthrow new InsufficientFundsException();\nelse {\nfromAcct.debit(amount);\ntoAcct.credit(amount);\n}\n}\n}\n\nint fromHash = System.identityHashCode(fromAcct);\nint toHash = System.identityHashCode(toAcct);\n\nif (fromHash < toHash) {\nsynchronized (fromAcct) {\nsynchronized (toAcct) {\nnew Helper().transfer();\n}\n}\n} else if (fromHash > toHash) {\nsynchronized (toAcct) {\nsynchronized (fromAcct) {\nnew Helper().transfer();\n}\n}\n} else {\nsynchronized (tieLock) {\nsynchronized (fromAcct) {\nsynchronized (toAcct) {\nnew Helper().transfer();\n}\n}\n}\n}\n}\n\npublic static class DollarAmount implements Comparable<DollarAmount> {\nprivate final BigDecimal value;\n\npublic DollarAmount(BigDecimal value) {\nthis.value = value;\n}\n\npublic DollarAmount add(DollarAmount other) {\nreturn new DollarAmount(this.value.add(other.value));\n}\n\npublic DollarAmount subtract(DollarAmount other) {\nreturn new DollarAmount(this.value.subtract(other.value));\n}\n\n@Override\npublic int compareTo(DollarAmount other) {\nreturn this.value.compareTo(other.value);\n}\n\n@Override\npublic String toString() {\nreturn value.toString();\n}\n}\n\npublic interface Account {\nvoid debit(DollarAmount d);\n\nvoid credit(DollarAmount d);\n\nDollarAmount getBalance();\n\nint getAcctNo();\n}\n\npublic static class AccountImpl implements Account {\nprivate DollarAmount balance;\nprivate final int acctNo;\n\npublic AccountImpl(int acctNo, DollarAmount initialBalance) {\nthis.acctNo = acctNo;\nthis.balance = initialBalance;\n}\n\n@Override\npublic synchronized void debit(DollarAmount d) {\nbalance = balance.subtract(d);\n}\n\n@Override\npublic synchronized void credit(DollarAmount d) {\nbalance = balance.add(d);\n}\n\n@Override\npublic synchronized DollarAmount getBalance() {\nreturn balance;\n}\n\n@Override\npublic int getAcctNo() {\nreturn acctNo;\n}\n}\n\nstatic class InsufficientFundsException extends Exception {\npublic InsufficientFundsException() {\nsuper(\"Insufficient funds in account.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC service = new LLMC();\n\nAccount a1 = new AccountImpl(1, new DollarAmount(new BigDecimal(\"1000.00\")));\nAccount a2 = new AccountImpl(2, new DollarAmount(new BigDecimal(\"1000.00\")));\n\nRunnable task = () -> {\ntry {\n// Reduced iterations to 2 for faster completion\nfor (int i = 0; i < 2; i++) {\nservice.transferMoney(a1, a2, new DollarAmount(new BigDecimal(\"1.00\")));\nservice.transferMoney(a2, a1, new DollarAmount(new BigDecimal(\"1.00\")));\n}\n} catch (InsufficientFundsException e) {\ne.printStackTrace();\n}\n};\n\n// Reduced thread pool size to 2 to reduce thread overhead\nExecutorService executor = Executors.newFixedThreadPool(2);\n// Reduced number of tasks to 2\nfor (int i = 0; i < 2; i++) {\nexecutor.submit(task);\n}\n\nexecutor.shutdown();\nwhile (!executor.isTerminated()) {\nThread.sleep(10);\n}\n\nSystem.out.println(\"Final balance of Account 1: \" + ((AccountImpl) a1).getBalance());\nSystem.out.println(\"Final balance of Account 2: \" + ((AccountImpl) a2).getBalance());\n}\n}",
        "max_depth": "211",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.51%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.69%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.72%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=148723,visited=128290,backtracked=274938,end=86\nsearch:             maxDepth=2110,constraints=61866\nchoice generators:  thread=95548 (signal=0,lock=774,sharedRef=75423,threadApi=2,reschedule=4397), data=0\nheap:               new=500369,released=313520,maxLive=755,gcCycles=277013\ninstructions:       37887890\nmax memory:         1017MB\nloaded code:        classes=141,methods=2423\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.25%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.26%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field VaultNodeImpl@1c9.crystalBalance   ...\"\n\n====================================================== statistics\nstates:             new=87578,visited=16513,backtracked=101981,end=0\nsearch:             maxDepth=2110,constraints=59110\nchoice generators:  thread=36140 (signal=0,lock=263,sharedRef=21695,threadApi=2,reschedule=29), data=0\nheap:               new=36763,released=20933,maxLive=755,gcCycles=104090\ninstructions:       4653341\nmax memory:         995MB\nloaded code:        classes=141,methods=2424\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.13%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.30%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.26%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=135624,visited=97188,backtracked=230719,end=8\nsearch:             maxDepth=2110,constraints=63992\nchoice generators:  thread=81043 (signal=0,lock=25,sharedRef=57731,threadApi=3437,reschedule=419), data=0\nheap:               new=284297,released=115607,maxLive=765,gcCycles=232812\ninstructions:       60987761\nmax memory:         1014MB\nloaded code:        classes=142,methods=2473\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field VaultNodeImpl@1c9.crystalBalance   ...\"",
            "no errors detected"
        ],
        "codebleu_score": [
            52.04,
            54.45,
            55.4
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface CrystalAmount {\n    long getValue();\n}\n\ninterface VaultNode {\n    long getCrystals();\n    void setCrystals(long crystals);\n    ReentrantLock getLock();\n}\n\nclass InsufficientCrystalsException extends Exception {\n    public InsufficientCrystalsException(String message) {\n        super(message);\n    }\n}\n\nclass SimpleCrystalAmount implements CrystalAmount {\n    private final long value;\n    \n    public SimpleCrystalAmount(long value) {\n        this.value = value;\n    }\n    \n    public long getValue() {\n        return value;\n    }\n}\n\nclass SimpleVaultNode implements VaultNode {\n    private long crystals;\n    private final ReentrantLock lock;\n    \n    public SimpleVaultNode(long initialCrystals) {\n        this.crystals = initialCrystals;\n        this.lock = new ReentrantLock();\n    }\n    \n    public long getCrystals() {\n        return crystals;\n    }\n    \n    public void setCrystals(long crystals) {\n        this.crystals = crystals;\n    }\n    \n    public ReentrantLock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final ReentrantLock tieBreakerLock = new ReentrantLock();\n    \n    public static void performTransfer(VaultNode from, VaultNode to, CrystalAmount amount) throws InsufficientCrystalsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    executeTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    executeTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        executeTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void executeTransfer(VaultNode from, VaultNode to, CrystalAmount amount) throws InsufficientCrystalsException {\n        long transferAmount = amount.getValue();\n        if (from.getCrystals() < transferAmount) {\n            throw new InsufficientCrystalsException(\"Insufficient crystals for transfer\");\n        }\n        from.setCrystals(from.getCrystals() - transferAmount);\n        to.setCrystals(to.getCrystals() + transferAmount);\n    }\n}\n\npublic class CrystalTransfer {\n    public static void main(String[] args) {\n        VaultNode vault1 = new SimpleVaultNode(1000);\n        VaultNode vault2 = new SimpleVaultNode(500);\n        VaultNode vault3 = new SimpleVaultNode(200);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                TransferHelper.performTransfer(vault1, vault2, new SimpleCrystalAmount(100));\n                System.out.println(\"Transfer 1 completed\");\n            } catch (InsufficientCrystalsException e) {\n                System.out.println(\"Transfer 1 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                TransferHelper.performTransfer(vault2, vault3, new SimpleCrystalAmount(50));\n                System.out.println(\"Transfer 2 completed\");\n            } catch (InsufficientCrystalsException e) {\n                System.out.println(\"Transfer 2 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Vault 1: \" + vault1.getCrystals());\n        System.out.println(\"Vault 2: \" + vault2.getCrystals());\n        System.out.println(\"Vault 3: \" + vault3.getCrystals());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface CrystalAmount {\n    long getAmount();\n}\n\ninterface VaultNode {\n    void withdraw(CrystalAmount amount) throws InsufficientCrystalsException;\n    void deposit(CrystalAmount amount);\n    long getCrystalBalance();\n}\n\nclass InsufficientCrystalsException extends Exception {\n    public InsufficientCrystalsException(String message) {\n        super(message);\n    }\n}\n\nclass CrystalAmountImpl implements CrystalAmount {\n    private final long amount;\n    \n    public CrystalAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass VaultNodeImpl implements VaultNode {\n    private long crystalBalance;\n    private final ReentrantLock lock = new ReentrantLock();\n    \n    public VaultNodeImpl(long initialBalance) {\n        this.crystalBalance = initialBalance;\n    }\n    \n    @Override\n    public void withdraw(CrystalAmount amount) throws InsufficientCrystalsException {\n        if (crystalBalance < amount.getAmount()) {\n            throw new InsufficientCrystalsException(\"Insufficient crystals for withdrawal\");\n        }\n        crystalBalance -= amount.getAmount();\n    }\n    \n    @Override\n    public void deposit(CrystalAmount amount) {\n        crystalBalance += amount.getAmount();\n    }\n    \n    @Override\n    public long getCrystalBalance() {\n        return crystalBalance;\n    }\n    \n    public ReentrantLock getLock() {\n        return lock;\n    }\n}\n\nclass CrystalTransferHelper {\n    private static final ReentrantLock tieBreakerLock = new ReentrantLock();\n    \n    public static void performTransfer(VaultNodeImpl source, VaultNodeImpl destination, CrystalAmount amount) \n            throws InsufficientCrystalsException {\n        int sourceHash = System.identityHashCode(source);\n        int destHash = System.identityHashCode(destination);\n        \n        if (sourceHash < destHash) {\n            source.getLock().lock();\n            try {\n                destination.getLock().lock();\n                try {\n                    executeTransfer(source, destination, amount);\n                } finally {\n                    destination.getLock().unlock();\n                }\n            } finally {\n                source.getLock().unlock();\n            }\n        } else if (sourceHash > destHash) {\n            destination.getLock().lock();\n            try {\n                source.getLock().lock();\n                try {\n                    executeTransfer(source, destination, amount);\n                } finally {\n                    source.getLock().unlock();\n                }\n            } finally {\n                destination.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                source.getLock().lock();\n                try {\n                    destination.getLock().lock();\n                    try {\n                        executeTransfer(source, destination, amount);\n                    } finally {\n                        destination.getLock().unlock();\n                    }\n                } finally {\n                    source.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private static void executeTransfer(VaultNodeImpl source, VaultNodeImpl destination, CrystalAmount amount) \n            throws InsufficientCrystalsException {\n        source.withdraw(amount);\n        destination.deposit(amount);\n    }\n}\n\npublic class CrystalTransferProgram {\n    public static void main(String[] args) {\n        VaultNodeImpl vault1 = new VaultNodeImpl(1000);\n        VaultNodeImpl vault2 = new VaultNodeImpl(500);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                CrystalAmount amount = new CrystalAmountImpl(100);\n                CrystalTransferHelper.performTransfer(vault1, vault2, amount);\n                System.out.println(\"Transfer 1 completed: Vault1=\" + vault1.getCrystalBalance() + \n                                 \", Vault2=\" + vault2.getCrystalBalance());\n            } catch (InsufficientCrystalsException e) {\n                System.out.println(\"Transfer 1 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                CrystalAmount amount = new CrystalAmountImpl(50);\n                CrystalTransferHelper.performTransfer(vault2, vault1, amount);\n                System.out.println(\"Transfer 2 completed: Vault1=\" + vault1.getCrystalBalance() + \n                                 \", Vault2=\" + vault2.getCrystalBalance());\n            } catch (InsufficientCrystalsException e) {\n                System.out.println(\"Transfer 2 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final balances: Vault1=\" + vault1.getCrystalBalance() + \n                         \", Vault2=\" + vault2.getCrystalBalance());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface CrystalAmount {\n    long getAmount();\n}\n\ninterface VaultNode {\n    long getCrystals();\n    void setCrystals(long crystals);\n    ReentrantLock getLock();\n}\n\nclass InsufficientCrystalsException extends Exception {\n    public InsufficientCrystalsException(String message) {\n        super(message);\n    }\n}\n\nclass CrystalAmountImpl implements CrystalAmount {\n    private final long amount;\n    \n    public CrystalAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    @Override\n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass VaultNodeImpl implements VaultNode {\n    private long crystals;\n    private final ReentrantLock lock = new ReentrantLock();\n    \n    public VaultNodeImpl(long initialCrystals) {\n        this.crystals = initialCrystals;\n    }\n    \n    @Override\n    public long getCrystals() {\n        return crystals;\n    }\n    \n    @Override\n    public void setCrystals(long crystals) {\n        this.crystals = crystals;\n    }\n    \n    @Override\n    public ReentrantLock getLock() {\n        return lock;\n    }\n}\n\nclass TransferRite {\n    private static final ReentrantLock tieBreakerLock = new ReentrantLock();\n    \n    public void performTransfer(VaultNode from, VaultNode to, CrystalAmount amount) throws InsufficientCrystalsException {\n        int fromHash = System.identityHashCode(from);\n        int toHash = System.identityHashCode(to);\n        \n        if (fromHash < toHash) {\n            from.getLock().lock();\n            try {\n                to.getLock().lock();\n                try {\n                    executeTransfer(from, to, amount);\n                } finally {\n                    to.getLock().unlock();\n                }\n            } finally {\n                from.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            to.getLock().lock();\n            try {\n                from.getLock().lock();\n                try {\n                    executeTransfer(from, to, amount);\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                to.getLock().unlock();\n            }\n        } else {\n            tieBreakerLock.lock();\n            try {\n                from.getLock().lock();\n                try {\n                    to.getLock().lock();\n                    try {\n                        executeTransfer(from, to, amount);\n                    } finally {\n                        to.getLock().unlock();\n                    }\n                } finally {\n                    from.getLock().unlock();\n                }\n            } finally {\n                tieBreakerLock.unlock();\n            }\n        }\n    }\n    \n    private void executeTransfer(VaultNode from, VaultNode to, CrystalAmount amount) throws InsufficientCrystalsException {\n        if (from.getCrystals() < amount.getAmount()) {\n            throw new InsufficientCrystalsException(\"Insufficient crystals in source vault\");\n        }\n        from.setCrystals(from.getCrystals() - amount.getAmount());\n        to.setCrystals(to.getCrystals() + amount.getAmount());\n    }\n}\n\npublic class CrystalTransferProgram {\n    public static void main(String[] args) {\n        VaultNode vault1 = new VaultNodeImpl(1000);\n        VaultNode vault2 = new VaultNodeImpl(500);\n        VaultNode vault3 = new VaultNodeImpl(200);\n        \n        TransferRite transferRite = new TransferRite();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    transferRite.performTransfer(vault1, vault2, new CrystalAmountImpl(50));\n                    System.out.println(\"Thread 1: Transferred 50 crystals from vault1 to vault2\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientCrystalsException | InterruptedException e) {\n                System.out.println(\"Thread 1 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    transferRite.performTransfer(vault2, vault3, new CrystalAmountImpl(30));\n                    System.out.println(\"Thread 2: Transferred 30 crystals from vault2 to vault3\");\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientCrystalsException | InterruptedException e) {\n                System.out.println(\"Thread 2 error: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"Final vault1 crystals: \" + vault1.getCrystals());\n        System.out.println(\"Final vault2 crystals: \" + vault2.getCrystals());\n        System.out.println(\"Final vault3 crystals: \" + vault3.getCrystals());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Bounded buffer using Semaphore. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java implementation of a magical orb vault (circular vault) using semaphores for synchronization. The vault should support simultaneous access from multiple sorcerers, ensuring thread-safe placement and retrieval of orbs. Use two semaphores to track the number of available orbs and remaining slots in the vault. Implement methods put(Orb x) to place an orb into the vault and take() to remove and return an orb from the vault, both blocking when necessary until space or orbs become available. Also include helper methods isEmpty() and isFull() to check the current state of the vault. Ensure that internal vault manipulation is synchronized to prevent chaotic collisions during concurrent access. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.LinkedList;\nimport java.util.Queue;\n\nclass Orb {\n    private final int id;\n    private final String type;\n    \n    public Orb(int id, String type) {\n        this.id = id;\n        this.type = type;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Orb{id=\" + id + \", type='\" + type + \"'}\";\n    }\n}\n\nclass MagicalOrbVault {\n    private final int capacity;\n    private final Queue<Orb> vault;\n    private final Semaphore availableOrbs;\n    private final Semaphore availableSlots;\n    private final Object lock = new Object();\n    \n    public MagicalOrbVault(int capacity) {\n        this.capacity = capacity;\n        this.vault = new LinkedList<>();\n        this.availableOrbs = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n    }\n    \n    public void put(Orb orb) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            vault.offer(orb);\n        }\n        availableOrbs.release();\n    }\n    \n    public Orb take() throws InterruptedException {\n        availableOrbs.acquire();\n        Orb orb;\n        synchronized (lock) {\n            orb = vault.poll();\n        }\n        availableSlots.release();\n        return orb;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return vault.isEmpty();\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return vault.size() == capacity;\n        }\n    }\n}\n\npublic class MagicalOrbVaultDemo {\n    public static void main(String[] args) {\n        MagicalOrbVault vault = new MagicalOrbVault(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 1; i <= 7; i++) {\n                    Orb orb = new Orb(i, i % 2 == 0 ? \"Fire\" : \"Ice\");\n                    System.out.println(\"Sorcerer 1 placing: \" + orb);\n                    vault.put(orb);\n                    System.out.println(\"Sorcerer 1 placed: \" + orb + \", Full: \" + vault.isFull());\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(200);\n                for (int i = 0; i < 7; i++) {\n                    System.out.println(\"Sorcerer 2 attempting to take orb...\");\n                    Orb orb = vault.take();\n                    System.out.println(\"Sorcerer 2 retrieved: \" + orb + \", Empty: \" + vault.isEmpty());\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.LinkedList;\nimport java.util.Queue;\n\nclass Orb {\n    private final int id;\n    private final String color;\n    \n    public Orb(int id, String color) {\n        this.id = id;\n        this.color = color;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Orb{id=\" + id + \", color='\" + color + \"'}\";\n    }\n}\n\nclass MagicalOrbVault {\n    private final int capacity;\n    private final Queue<Orb> vault;\n    private final Semaphore availableOrbs;\n    private final Semaphore availableSlots;\n    private final Object lock = new Object();\n    \n    public MagicalOrbVault(int capacity) {\n        this.capacity = capacity;\n        this.vault = new LinkedList<>();\n        this.availableOrbs = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n    }\n    \n    public void put(Orb orb) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            vault.offer(orb);\n            System.out.println(Thread.currentThread().getName() + \" placed \" + orb);\n        }\n        availableOrbs.release();\n    }\n    \n    public Orb take() throws InterruptedException {\n        availableOrbs.acquire();\n        Orb orb;\n        synchronized (lock) {\n            orb = vault.poll();\n            System.out.println(Thread.currentThread().getName() + \" retrieved \" + orb);\n        }\n        availableSlots.release();\n        return orb;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return vault.isEmpty();\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return vault.size() == capacity;\n        }\n    }\n}\n\nclass Sorcerer implements Runnable {\n    private final MagicalOrbVault vault;\n    private final boolean isProducer;\n    private final int operations;\n    \n    public Sorcerer(MagicalOrbVault vault, boolean isProducer, int operations) {\n        this.vault = vault;\n        this.isProducer = isProducer;\n        this.operations = operations;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < operations; i++) {\n                if (isProducer) {\n                    Orb orb = new Orb(i, \"Magic\");\n                    vault.put(orb);\n                    Thread.sleep(100);\n                } else {\n                    Orb orb = vault.take();\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class MagicalOrbVaultSystem {\n    public static void main(String[] args) {\n        MagicalOrbVault vault = new MagicalOrbVault(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(new Sorcerer(vault, true, 10));\n        executor.submit(new Sorcerer(vault, false, 10));\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Vault is empty: \" + vault.isEmpty());\n        System.out.println(\"Vault is full: \" + vault.isFull());\n    }\n}",
            "import java.util.concurrent.Semaphore;\nimport java.util.LinkedList;\nimport java.util.Queue;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Orb {\n    private final String name;\n    private final int power;\n    \n    public Orb(String name, int power) {\n        this.name = name;\n        this.power = power;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Orb{name='\" + name + \"', power=\" + power + \"}\";\n    }\n}\n\nclass MagicalOrbVault {\n    private final int capacity;\n    private final Queue<Orb> vault;\n    private final Semaphore availableOrbs;\n    private final Semaphore availableSlots;\n    private final Object lock = new Object();\n    \n    public MagicalOrbVault(int capacity) {\n        this.capacity = capacity;\n        this.vault = new LinkedList<>();\n        this.availableOrbs = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n    }\n    \n    public void put(Orb orb) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            vault.offer(orb);\n        }\n        availableOrbs.release();\n    }\n    \n    public Orb take() throws InterruptedException {\n        availableOrbs.acquire();\n        Orb orb;\n        synchronized (lock) {\n            orb = vault.poll();\n        }\n        availableSlots.release();\n        return orb;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return vault.isEmpty();\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return vault.size() == capacity;\n        }\n    }\n}\n\npublic class MagicalOrbVaultDemo {\n    public static void main(String[] args) {\n        MagicalOrbVault vault = new MagicalOrbVault(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 1; i <= 8; i++) {\n                    Orb orb = new Orb(\"Fire-\" + i, i * 10);\n                    System.out.println(\"Sorcerer1 placing: \" + orb);\n                    vault.put(orb);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(300);\n                for (int i = 1; i <= 8; i++) {\n                    Orb orb = vault.take();\n                    System.out.println(\"Sorcerer2 retrieved: \" + orb);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.Semaphore;\n\npublic class SemaphoreBoundedBuffer<E> {\nprivate final Semaphore availableItems, availableSpaces;\nprivate final E[] items;\nprivate int putPosition = 0, takePosition = 0;\n\npublic SemaphoreBoundedBuffer(int capacity) {\nif (capacity <= 0) throw new IllegalArgumentException();\navailableItems = new Semaphore(0);\navailableSpaces = new Semaphore(capacity);\nitems = (E[]) new Object[capacity];\n}\n\npublic void put(E x) throws InterruptedException {\navailableSpaces.acquire();\nsynchronized (this) {\nitems[putPosition] = x;\nputPosition = (putPosition + 1) % items.length;\n}\navailableItems.release();\n}\n\npublic E take() throws InterruptedException {\navailableItems.acquire();\nE item;\nsynchronized (this) {\nitem = items[takePosition];\nitems[takePosition] = null;\ntakePosition = (takePosition + 1) % items.length;\n}\navailableSpaces.release();\nreturn item;\n}\n\npublic static void main(String[] args) {\nfinal int bufferSize = 2;\nfinal int numItems = 2;\n\nSemaphoreBoundedBuffer<Integer> buffer = new SemaphoreBoundedBuffer<>(bufferSize);\n\nThread producer = new Thread(() -> {\ntry {\nfor (int i = 0; i < numItems; i++) {\nbuffer.put(i);\n// Avoid printing to reduce state space\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n\nThread consumer = new Thread(() -> {\ntry {\nfor (int i = 0; i < numItems; i++) {\nInteger item = buffer.take();\n// Avoid printing to reduce state space\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n\nproducer.start();\nconsumer.start();\n\ntry {\nproducer.join();\nconsumer.join();\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n\n// Minimal output\nSystem.out.println(\"Done.\");\n}\n}",
        "max_depth": "71",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.81%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 62.96%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=154005,visited=124083,backtracked=277387,end=0\nsearch:             maxDepth=710,constraints=66118\nchoice generators:  thread=97720 (signal=0,lock=21520,sharedRef=52277,threadApi=8561,reschedule=58), data=0\nheap:               new=400904,released=672982,maxLive=790,gcCycles=274318\ninstructions:       30801688\nmax memory:         1019MB\nloaded code:        classes=143,methods=2519\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.06%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.31%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.69%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=200354,visited=75525,backtracked=275179,end=0\nsearch:             maxDepth=710,constraints=119411\nchoice generators:  thread=95562 (signal=0,lock=9426,sharedRef=53883,threadApi=3710,reschedule=12), data=0\nheap:               new=389325,released=166605,maxLive=778,gcCycles=273031\ninstructions:       23051074\nmax memory:         1018MB\nloaded code:        classes=144,methods=2517\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.69%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.87%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=197125,visited=76557,backtracked=272975,end=0\nsearch:             maxDepth=710,constraints=119069\nchoice generators:  thread=93759 (signal=0,lock=6975,sharedRef=55327,threadApi=5134,reschedule=22), data=0\nheap:               new=287729,released=352219,maxLive=789,gcCycles=271144\ninstructions:       20378621\nmax memory:         1018MB\nloaded code:        classes=143,methods=2519\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            53.21,
            58.34,
            52.99
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.LinkedList;\nimport java.util.Queue;\n\nclass Orb {\n    private final int id;\n    private final String type;\n    \n    public Orb(int id, String type) {\n        this.id = id;\n        this.type = type;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Orb{id=\" + id + \", type='\" + type + \"'}\";\n    }\n}\n\nclass MagicalOrbVault {\n    private final int capacity;\n    private final Queue<Orb> vault;\n    private final Semaphore availableOrbs;\n    private final Semaphore availableSlots;\n    private final Object lock = new Object();\n    \n    public MagicalOrbVault(int capacity) {\n        this.capacity = capacity;\n        this.vault = new LinkedList<>();\n        this.availableOrbs = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n    }\n    \n    public void put(Orb orb) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            vault.offer(orb);\n        }\n        availableOrbs.release();\n    }\n    \n    public Orb take() throws InterruptedException {\n        availableOrbs.acquire();\n        Orb orb;\n        synchronized (lock) {\n            orb = vault.poll();\n        }\n        availableSlots.release();\n        return orb;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return vault.isEmpty();\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return vault.size() == capacity;\n        }\n    }\n}\n\npublic class MagicalOrbVaultDemo {\n    public static void main(String[] args) {\n        MagicalOrbVault vault = new MagicalOrbVault(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 1; i <= 7; i++) {\n                    Orb orb = new Orb(i, i % 2 == 0 ? \"Fire\" : \"Ice\");\n                    System.out.println(\"Sorcerer 1 placing: \" + orb);\n                    vault.put(orb);\n                    System.out.println(\"Sorcerer 1 placed: \" + orb + \", Full: \" + vault.isFull());\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(200);\n                for (int i = 0; i < 7; i++) {\n                    System.out.println(\"Sorcerer 2 attempting to take orb...\");\n                    Orb orb = vault.take();\n                    System.out.println(\"Sorcerer 2 retrieved: \" + orb + \", Empty: \" + vault.isEmpty());\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.LinkedList;\nimport java.util.Queue;\n\nclass Orb {\n    private final int id;\n    private final String color;\n    \n    public Orb(int id, String color) {\n        this.id = id;\n        this.color = color;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Orb{id=\" + id + \", color='\" + color + \"'}\";\n    }\n}\n\nclass MagicalOrbVault {\n    private final int capacity;\n    private final Queue<Orb> vault;\n    private final Semaphore availableOrbs;\n    private final Semaphore availableSlots;\n    private final Object lock = new Object();\n    \n    public MagicalOrbVault(int capacity) {\n        this.capacity = capacity;\n        this.vault = new LinkedList<>();\n        this.availableOrbs = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n    }\n    \n    public void put(Orb orb) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            vault.offer(orb);\n            System.out.println(Thread.currentThread().getName() + \" placed \" + orb);\n        }\n        availableOrbs.release();\n    }\n    \n    public Orb take() throws InterruptedException {\n        availableOrbs.acquire();\n        Orb orb;\n        synchronized (lock) {\n            orb = vault.poll();\n            System.out.println(Thread.currentThread().getName() + \" retrieved \" + orb);\n        }\n        availableSlots.release();\n        return orb;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return vault.isEmpty();\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return vault.size() == capacity;\n        }\n    }\n}\n\nclass Sorcerer implements Runnable {\n    private final MagicalOrbVault vault;\n    private final boolean isProducer;\n    private final int operations;\n    \n    public Sorcerer(MagicalOrbVault vault, boolean isProducer, int operations) {\n        this.vault = vault;\n        this.isProducer = isProducer;\n        this.operations = operations;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < operations; i++) {\n                if (isProducer) {\n                    Orb orb = new Orb(i, \"Magic\");\n                    vault.put(orb);\n                    Thread.sleep(100);\n                } else {\n                    Orb orb = vault.take();\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class MagicalOrbVaultSystem {\n    public static void main(String[] args) {\n        MagicalOrbVault vault = new MagicalOrbVault(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(new Sorcerer(vault, true, 10));\n        executor.submit(new Sorcerer(vault, false, 10));\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Vault is empty: \" + vault.isEmpty());\n        System.out.println(\"Vault is full: \" + vault.isFull());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.Semaphore;\nimport java.util.LinkedList;\nimport java.util.Queue;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Orb {\n    private final String name;\n    private final int power;\n    \n    public Orb(String name, int power) {\n        this.name = name;\n        this.power = power;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Orb{name='\" + name + \"', power=\" + power + \"}\";\n    }\n}\n\nclass MagicalOrbVault {\n    private final int capacity;\n    private final Queue<Orb> vault;\n    private final Semaphore availableOrbs;\n    private final Semaphore availableSlots;\n    private final Object lock = new Object();\n    \n    public MagicalOrbVault(int capacity) {\n        this.capacity = capacity;\n        this.vault = new LinkedList<>();\n        this.availableOrbs = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n    }\n    \n    public void put(Orb orb) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            vault.offer(orb);\n        }\n        availableOrbs.release();\n    }\n    \n    public Orb take() throws InterruptedException {\n        availableOrbs.acquire();\n        Orb orb;\n        synchronized (lock) {\n            orb = vault.poll();\n        }\n        availableSlots.release();\n        return orb;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return vault.isEmpty();\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return vault.size() == capacity;\n        }\n    }\n}\n\npublic class MagicalOrbVaultDemo {\n    public static void main(String[] args) {\n        MagicalOrbVault vault = new MagicalOrbVault(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 1; i <= 8; i++) {\n                    Orb orb = new Orb(\"Fire-\" + i, i * 10);\n                    System.out.println(\"Sorcerer1 placing: \" + orb);\n                    vault.put(orb);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(300);\n                for (int i = 1; i <= 8; i++) {\n                    Orb orb = vault.take();\n                    System.out.println(\"Sorcerer2 retrieved: \" + orb);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Bounded buffer using Semaphore. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java implementation of a crystal carousel (circular buffer) using semaphores for synchronization. The carousel should support concurrent access by multiple wizards, ensuring thread-safe insertion and extraction of crystals. Use two semaphores to track the number of available crystals and free slots in the carousel. Implement methods put(Crystal x) to place a crystal into the carousel and take() to retrieve and return a crystal, both blocking when necessary until space or crystals are available. Also include helper methods isEmpty() and isFull() to check the current status of the carousel. Ensure that internal carousel manipulation is synchronized to prevent clashes during simultaneous access. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Crystal {\n    private final int id;\n    private final String type;\n    \n    public Crystal(int id, String type) {\n        this.id = id;\n        this.type = type;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Crystal{id=\" + id + \", type='\" + type + \"'}\";\n    }\n}\n\nclass CrystalCarousel {\n    private final Crystal[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availableSlots;\n    private final Semaphore availableCrystals;\n    private final Object lock;\n    \n    public CrystalCarousel(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Crystal[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availableSlots = new Semaphore(capacity);\n        this.availableCrystals = new Semaphore(0);\n        this.lock = new Object();\n    }\n    \n    public void put(Crystal x) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = x;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availableCrystals.release();\n    }\n    \n    public Crystal take() throws InterruptedException {\n        availableCrystals.acquire();\n        Crystal crystal;\n        synchronized (lock) {\n            crystal = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        availableSlots.release();\n        return crystal;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Wizard implements Runnable {\n    private final String name;\n    private final CrystalCarousel carousel;\n    private final boolean isProducer;\n    private final int operations;\n    \n    public Wizard(String name, CrystalCarousel carousel, boolean isProducer, int operations) {\n        this.name = name;\n        this.carousel = carousel;\n        this.isProducer = isProducer;\n        this.operations = operations;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < operations; i++) {\n                if (isProducer) {\n                    Crystal crystal = new Crystal(i, name + \"-Crystal\");\n                    carousel.put(crystal);\n                    System.out.println(name + \" placed: \" + crystal);\n                    Thread.sleep(100);\n                } else {\n                    Crystal crystal = carousel.take();\n                    System.out.println(name + \" retrieved: \" + crystal);\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class CrystalCarouselProgram {\n    public static void main(String[] args) {\n        CrystalCarousel carousel = new CrystalCarousel(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Wizard producer = new Wizard(\"ProducerWizard\", carousel, true, 10);\n        Wizard consumer = new Wizard(\"ConsumerWizard\", carousel, false, 10);\n        \n        executor.submit(producer);\n        executor.submit(consumer);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Carousel is empty: \" + carousel.isEmpty());\n        System.out.println(\"Carousel is full: \" + carousel.isFull());\n    }\n}",
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Crystal {\n    private final String type;\n    private final int power;\n    \n    public Crystal(String type, int power) {\n        this.type = type;\n        this.power = power;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Crystal{type='\" + type + \"', power=\" + power + \"}\";\n    }\n}\n\nclass CrystalCarousel {\n    private final Crystal[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availableCrystals;\n    private final Semaphore freeSlots;\n    private final Object lock;\n    \n    public CrystalCarousel(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Crystal[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availableCrystals = new Semaphore(0);\n        this.freeSlots = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n    \n    public void put(Crystal crystal) throws InterruptedException {\n        freeSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = crystal;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availableCrystals.release();\n    }\n    \n    public Crystal take() throws InterruptedException {\n        availableCrystals.acquire();\n        Crystal crystal;\n        synchronized (lock) {\n            crystal = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        freeSlots.release();\n        return crystal;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Wizard implements Runnable {\n    private final String name;\n    private final CrystalCarousel carousel;\n    private final boolean isProducer;\n    private final int operations;\n    \n    public Wizard(String name, CrystalCarousel carousel, boolean isProducer, int operations) {\n        this.name = name;\n        this.carousel = carousel;\n        this.isProducer = isProducer;\n        this.operations = operations;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < operations; i++) {\n                if (isProducer) {\n                    Crystal crystal = new Crystal(\"Magic-\" + i, i * 10);\n                    carousel.put(crystal);\n                    System.out.println(name + \" placed: \" + crystal);\n                    Thread.sleep(100);\n                } else {\n                    Crystal crystal = carousel.take();\n                    System.out.println(name + \" retrieved: \" + crystal);\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class CrystalCarouselDemo {\n    public static void main(String[] args) {\n        CrystalCarousel carousel = new CrystalCarousel(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Wizard producer = new Wizard(\"ProducerWizard\", carousel, true, 10);\n        Wizard consumer = new Wizard(\"ConsumerWizard\", carousel, false, 10);\n        \n        executor.submit(producer);\n        executor.submit(consumer);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Carousel empty: \" + carousel.isEmpty());\n        System.out.println(\"Carousel full: \" + carousel.isFull());\n    }\n}",
            "import java.util.concurrent.*;\nimport java.util.Random;\n\nclass Crystal {\n    private final int id;\n    private final String type;\n    \n    public Crystal(int id, String type) {\n        this.id = id;\n        this.type = type;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Crystal{id=\" + id + \", type='\" + type + \"'}\";\n    }\n}\n\nclass CrystalCarousel {\n    private final Crystal[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availableCrystals;\n    private final Semaphore availableSlots;\n    private final Object lock;\n    \n    public CrystalCarousel(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Crystal[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availableCrystals = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n    \n    public void put(Crystal x) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = x;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availableCrystals.release();\n    }\n    \n    public Crystal take() throws InterruptedException {\n        availableCrystals.acquire();\n        Crystal crystal;\n        synchronized (lock) {\n            crystal = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        availableSlots.release();\n        return crystal;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Wizard implements Runnable {\n    private final String name;\n    private final CrystalCarousel carousel;\n    private final boolean isProducer;\n    private final Random random;\n    \n    public Wizard(String name, CrystalCarousel carousel, boolean isProducer) {\n        this.name = name;\n        this.carousel = carousel;\n        this.isProducer = isProducer;\n        this.random = new Random();\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < 5; i++) {\n                if (isProducer) {\n                    Crystal crystal = new Crystal(i, name + \"-Crystal\");\n                    System.out.println(name + \" is placing \" + crystal);\n                    carousel.put(crystal);\n                    System.out.println(name + \" placed \" + crystal);\n                } else {\n                    System.out.println(name + \" is retrieving a crystal\");\n                    Crystal crystal = carousel.take();\n                    System.out.println(name + \" retrieved \" + crystal);\n                }\n                Thread.sleep(random.nextInt(500) + 100);\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class CrystalCarouselDemo {\n    public static void main(String[] args) {\n        CrystalCarousel carousel = new CrystalCarousel(3);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Wizard producer = new Wizard(\"Merlin\", carousel, true);\n        Wizard consumer = new Wizard(\"Gandalf\", carousel, false);\n        \n        executor.submit(producer);\n        executor.submit(consumer);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Carousel is empty: \" + carousel.isEmpty());\n        System.out.println(\"Carousel is full: \" + carousel.isFull());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.Semaphore;\n\npublic class SemaphoreBoundedBuffer<E> {\nprivate final Semaphore availableItems, availableSpaces;\nprivate final E[] items;\nprivate int putPosition = 0, takePosition = 0;\n\npublic SemaphoreBoundedBuffer(int capacity) {\nif (capacity <= 0) throw new IllegalArgumentException();\navailableItems = new Semaphore(0);\navailableSpaces = new Semaphore(capacity);\nitems = (E[]) new Object[capacity];\n}\n\npublic void put(E x) throws InterruptedException {\navailableSpaces.acquire();\nsynchronized (this) {\nitems[putPosition] = x;\nputPosition = (putPosition + 1) % items.length;\n}\navailableItems.release();\n}\n\npublic E take() throws InterruptedException {\navailableItems.acquire();\nE item;\nsynchronized (this) {\nitem = items[takePosition];\nitems[takePosition] = null;\ntakePosition = (takePosition + 1) % items.length;\n}\navailableSpaces.release();\nreturn item;\n}\n\npublic static void main(String[] args) {\nfinal int bufferSize = 2;\nfinal int numItems = 2;\n\nSemaphoreBoundedBuffer<Integer> buffer = new SemaphoreBoundedBuffer<>(bufferSize);\n\nThread producer = new Thread(() -> {\ntry {\nfor (int i = 0; i < numItems; i++) {\nbuffer.put(i);\n// Avoid printing to reduce state space\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n\nThread consumer = new Thread(() -> {\ntry {\nfor (int i = 0; i < numItems; i++) {\nInteger item = buffer.take();\n// Avoid printing to reduce state space\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n\nproducer.start();\nconsumer.start();\n\ntry {\nproducer.join();\nconsumer.join();\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n\n// Minimal output\nSystem.out.println(\"Done.\");\n}\n}",
        "max_depth": "71",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.06%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.33%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=194250,visited=71880,backtracked=265423,end=0\nsearch:             maxDepth=710,constraints=116417\nchoice generators:  thread=92105 (signal=0,lock=9337,sharedRef=49026,threadApi=3799,reschedule=2237), data=0\nheap:               new=453875,released=221618,maxLive=783,gcCycles=266130\ninstructions:       22263092\nmax memory:         1019MB\nloaded code:        classes=140,methods=2424\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.06%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.32%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.49%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=192587,visited=72004,backtracked=263888,end=0\nsearch:             maxDepth=710,constraints=115153\nchoice generators:  thread=91602 (signal=0,lock=9416,sharedRef=48705,threadApi=3845,reschedule=2254), data=0\nheap:               new=432072,released=199828,maxLive=783,gcCycles=264591\ninstructions:       22256534\nmax memory:         1019MB\nloaded code:        classes=140,methods=2424\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.08%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.13%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.34%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=181517,visited=66200,backtracked=247018,end=0\nsearch:             maxDepth=710,constraints=108962\nchoice generators:  thread=86074 (signal=0,lock=8562,sharedRef=44852,threadApi=3576,reschedule=2270), data=0\nheap:               new=725258,released=426840,maxLive=788,gcCycles=247717\ninstructions:       22331082\nmax memory:         1019MB\nloaded code:        classes=141,methods=2436\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            57.76,
            57.28,
            54.38
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Crystal {\n    private final int id;\n    private final String type;\n    \n    public Crystal(int id, String type) {\n        this.id = id;\n        this.type = type;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Crystal{id=\" + id + \", type='\" + type + \"'}\";\n    }\n}\n\nclass CrystalCarousel {\n    private final Crystal[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availableSlots;\n    private final Semaphore availableCrystals;\n    private final Object lock;\n    \n    public CrystalCarousel(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Crystal[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availableSlots = new Semaphore(capacity);\n        this.availableCrystals = new Semaphore(0);\n        this.lock = new Object();\n    }\n    \n    public void put(Crystal x) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = x;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availableCrystals.release();\n    }\n    \n    public Crystal take() throws InterruptedException {\n        availableCrystals.acquire();\n        Crystal crystal;\n        synchronized (lock) {\n            crystal = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        availableSlots.release();\n        return crystal;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Wizard implements Runnable {\n    private final String name;\n    private final CrystalCarousel carousel;\n    private final boolean isProducer;\n    private final int operations;\n    \n    public Wizard(String name, CrystalCarousel carousel, boolean isProducer, int operations) {\n        this.name = name;\n        this.carousel = carousel;\n        this.isProducer = isProducer;\n        this.operations = operations;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < operations; i++) {\n                if (isProducer) {\n                    Crystal crystal = new Crystal(i, name + \"-Crystal\");\n                    carousel.put(crystal);\n                    System.out.println(name + \" placed: \" + crystal);\n                    Thread.sleep(100);\n                } else {\n                    Crystal crystal = carousel.take();\n                    System.out.println(name + \" retrieved: \" + crystal);\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class CrystalCarouselProgram {\n    public static void main(String[] args) {\n        CrystalCarousel carousel = new CrystalCarousel(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Wizard producer = new Wizard(\"ProducerWizard\", carousel, true, 10);\n        Wizard consumer = new Wizard(\"ConsumerWizard\", carousel, false, 10);\n        \n        executor.submit(producer);\n        executor.submit(consumer);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Carousel is empty: \" + carousel.isEmpty());\n        System.out.println(\"Carousel is full: \" + carousel.isFull());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Crystal {\n    private final String type;\n    private final int power;\n    \n    public Crystal(String type, int power) {\n        this.type = type;\n        this.power = power;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Crystal{type='\" + type + \"', power=\" + power + \"}\";\n    }\n}\n\nclass CrystalCarousel {\n    private final Crystal[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availableCrystals;\n    private final Semaphore freeSlots;\n    private final Object lock;\n    \n    public CrystalCarousel(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Crystal[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availableCrystals = new Semaphore(0);\n        this.freeSlots = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n    \n    public void put(Crystal crystal) throws InterruptedException {\n        freeSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = crystal;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availableCrystals.release();\n    }\n    \n    public Crystal take() throws InterruptedException {\n        availableCrystals.acquire();\n        Crystal crystal;\n        synchronized (lock) {\n            crystal = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        freeSlots.release();\n        return crystal;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Wizard implements Runnable {\n    private final String name;\n    private final CrystalCarousel carousel;\n    private final boolean isProducer;\n    private final int operations;\n    \n    public Wizard(String name, CrystalCarousel carousel, boolean isProducer, int operations) {\n        this.name = name;\n        this.carousel = carousel;\n        this.isProducer = isProducer;\n        this.operations = operations;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < operations; i++) {\n                if (isProducer) {\n                    Crystal crystal = new Crystal(\"Magic-\" + i, i * 10);\n                    carousel.put(crystal);\n                    System.out.println(name + \" placed: \" + crystal);\n                    Thread.sleep(100);\n                } else {\n                    Crystal crystal = carousel.take();\n                    System.out.println(name + \" retrieved: \" + crystal);\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class CrystalCarouselDemo {\n    public static void main(String[] args) {\n        CrystalCarousel carousel = new CrystalCarousel(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Wizard producer = new Wizard(\"ProducerWizard\", carousel, true, 10);\n        Wizard consumer = new Wizard(\"ConsumerWizard\", carousel, false, 10);\n        \n        executor.submit(producer);\n        executor.submit(consumer);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Carousel empty: \" + carousel.isEmpty());\n        System.out.println(\"Carousel full: \" + carousel.isFull());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.*;\nimport java.util.Random;\n\nclass Crystal {\n    private final int id;\n    private final String type;\n    \n    public Crystal(int id, String type) {\n        this.id = id;\n        this.type = type;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Crystal{id=\" + id + \", type='\" + type + \"'}\";\n    }\n}\n\nclass CrystalCarousel {\n    private final Crystal[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availableCrystals;\n    private final Semaphore availableSlots;\n    private final Object lock;\n    \n    public CrystalCarousel(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Crystal[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availableCrystals = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n    \n    public void put(Crystal x) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = x;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availableCrystals.release();\n    }\n    \n    public Crystal take() throws InterruptedException {\n        availableCrystals.acquire();\n        Crystal crystal;\n        synchronized (lock) {\n            crystal = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        availableSlots.release();\n        return crystal;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Wizard implements Runnable {\n    private final String name;\n    private final CrystalCarousel carousel;\n    private final boolean isProducer;\n    private final Random random;\n    \n    public Wizard(String name, CrystalCarousel carousel, boolean isProducer) {\n        this.name = name;\n        this.carousel = carousel;\n        this.isProducer = isProducer;\n        this.random = new Random();\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < 5; i++) {\n                if (isProducer) {\n                    Crystal crystal = new Crystal(i, name + \"-Crystal\");\n                    System.out.println(name + \" is placing \" + crystal);\n                    carousel.put(crystal);\n                    System.out.println(name + \" placed \" + crystal);\n                } else {\n                    System.out.println(name + \" is retrieving a crystal\");\n                    Crystal crystal = carousel.take();\n                    System.out.println(name + \" retrieved \" + crystal);\n                }\n                Thread.sleep(random.nextInt(500) + 100);\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class CrystalCarouselDemo {\n    public static void main(String[] args) {\n        CrystalCarousel carousel = new CrystalCarousel(3);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Wizard producer = new Wizard(\"Merlin\", carousel, true);\n        Wizard consumer = new Wizard(\"Gandalf\", carousel, false);\n        \n        executor.submit(producer);\n        executor.submit(consumer);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Carousel is empty: \" + carousel.isEmpty());\n        System.out.println(\"Carousel is full: \" + carousel.isFull());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Bounded buffer using Semaphore. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java implementation of a potion loop (circular buffer) using semaphores for synchronization. The loop should support simultaneous access by multiple alchemists, ensuring thread-safe addition and extraction of potions. Use two semaphores to track the number of available potions and open slots in the loop. Implement methods put(Potion x) to insert a potion into the loop and take() to remove and return a potion, both blocking when necessary until space or potions are available. Also include helper methods isEmpty() and isFull() to check the current condition of the loop. Ensure that internal loop manipulation is synchronized to prevent collisions during concurrent access. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Potion {\n    private final String name;\n    private final int strength;\n\n    public Potion(String name, int strength) {\n        this.name = name;\n        this.strength = strength;\n    }\n\n    @Override\n    public String toString() {\n        return name + \" (strength: \" + strength + \")\";\n    }\n}\n\nclass PotionLoop {\n    private final Potion[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availablePotions;\n    private final Semaphore availableSlots;\n    private final Object lock;\n\n    public PotionLoop(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Potion[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availablePotions = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n\n    public void put(Potion potion) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = potion;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availablePotions.release();\n    }\n\n    public Potion take() throws InterruptedException {\n        availablePotions.acquire();\n        Potion potion;\n        synchronized (lock) {\n            potion = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        availableSlots.release();\n        return potion;\n    }\n\n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n\n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Alchemist implements Runnable {\n    private final PotionLoop loop;\n    private final String name;\n    private final boolean isProducer;\n\n    public Alchemist(PotionLoop loop, String name, boolean isProducer) {\n        this.loop = loop;\n        this.name = name;\n        this.isProducer = isProducer;\n    }\n\n    @Override\n    public void run() {\n        try {\n            if (isProducer) {\n                for (int i = 0; i < 3; i++) {\n                    Potion potion = new Potion(name + \"-Potion-\" + i, i * 10);\n                    System.out.println(name + \" creating \" + potion);\n                    loop.put(potion);\n                    System.out.println(name + \" added \" + potion);\n                    Thread.sleep(100);\n                }\n            } else {\n                for (int i = 0; i < 3; i++) {\n                    System.out.println(name + \" waiting for potion...\");\n                    Potion potion = loop.take();\n                    System.out.println(name + \" extracted \" + potion);\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class PotionLoopDemo {\n    public static void main(String[] args) {\n        PotionLoop loop = new PotionLoop(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.execute(new Alchemist(loop, \"Producer-Alchemist\", true));\n        executor.execute(new Alchemist(loop, \"Consumer-Alchemist\", false));\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Loop is empty: \" + loop.isEmpty());\n        System.out.println(\"Loop is full: \" + loop.isFull());\n    }\n}",
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Potion {\n    private final String name;\n    private final int strength;\n    \n    public Potion(String name, int strength) {\n        this.name = name;\n        this.strength = strength;\n    }\n    \n    @Override\n    public String toString() {\n        return name + \" (strength: \" + strength + \")\";\n    }\n}\n\nclass PotionLoop {\n    private final Potion[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore available;\n    private final Semaphore spaces;\n    private final Object lock;\n    \n    public PotionLoop(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Potion[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.available = new Semaphore(0);\n        this.spaces = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n    \n    public void put(Potion x) throws InterruptedException {\n        spaces.acquire();\n        synchronized (lock) {\n            buffer[tail] = x;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        available.release();\n    }\n    \n    public Potion take() throws InterruptedException {\n        available.acquire();\n        Potion potion;\n        synchronized (lock) {\n            potion = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        spaces.release();\n        return potion;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Alchemist implements Runnable {\n    private final PotionLoop loop;\n    private final boolean isProducer;\n    private final int id;\n    \n    public Alchemist(PotionLoop loop, boolean isProducer, int id) {\n        this.loop = loop;\n        this.isProducer = isProducer;\n        this.id = id;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < 3; i++) {\n                if (isProducer) {\n                    Potion potion = new Potion(\"Potion-\" + id + \"-\" + i, (id + 1) * 10 + i);\n                    System.out.println(\"Alchemist \" + id + \" creating: \" + potion);\n                    loop.put(potion);\n                    System.out.println(\"Alchemist \" + id + \" added: \" + potion);\n                    Thread.sleep(100);\n                } else {\n                    Potion potion = loop.take();\n                    System.out.println(\"Alchemist \" + id + \" extracted: \" + potion);\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class PotionLoopDemo {\n    public static void main(String[] args) {\n        PotionLoop loop = new PotionLoop(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(new Alchemist(loop, true, 1));\n        executor.submit(new Alchemist(loop, false, 2));\n        \n        try {\n            Thread.sleep(500);\n            \n            loop.put(new Potion(\"HealthPotion\", 50));\n            loop.put(new Potion(\"ManaPotion\", 30));\n            \n            System.out.println(\"Is loop empty? \" + loop.isEmpty());\n            System.out.println(\"Is loop full? \" + loop.isFull());\n            \n            Potion taken = loop.take();\n            System.out.println(\"Main thread took: \" + taken);\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(2, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Potion {\n    private final String name;\n    private final int power;\n\n    public Potion(String name, int power) {\n        this.name = name;\n        this.power = power;\n    }\n\n    @Override\n    public String toString() {\n        return \"Potion{name='\" + name + \"', power=\" + power + \"}\";\n    }\n}\n\nclass PotionLoop {\n    private final Potion[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availablePotions;\n    private final Semaphore availableSlots;\n    private final Object lock;\n\n    public PotionLoop(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Potion[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availablePotions = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n\n    public void put(Potion x) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = x;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availablePotions.release();\n    }\n\n    public Potion take() throws InterruptedException {\n        availablePotions.acquire();\n        Potion potion;\n        synchronized (lock) {\n            potion = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        availableSlots.release();\n        return potion;\n    }\n\n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n\n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\npublic class PotionLoopDemo {\n    public static void main(String[] args) {\n        PotionLoop potionLoop = new PotionLoop(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Potion potion = new Potion(\"Healing-\" + i, 10 + i);\n                    System.out.println(\"Producer adding: \" + potion);\n                    potionLoop.put(potion);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Potion potion = potionLoop.take();\n                    System.out.println(\"Consumer took: \" + potion);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.Semaphore;\n\npublic class SemaphoreBoundedBuffer<E> {\nprivate final Semaphore availableItems, availableSpaces;\nprivate final E[] items;\nprivate int putPosition = 0, takePosition = 0;\n\npublic SemaphoreBoundedBuffer(int capacity) {\nif (capacity <= 0) throw new IllegalArgumentException();\navailableItems = new Semaphore(0);\navailableSpaces = new Semaphore(capacity);\nitems = (E[]) new Object[capacity];\n}\n\npublic void put(E x) throws InterruptedException {\navailableSpaces.acquire();\nsynchronized (this) {\nitems[putPosition] = x;\nputPosition = (putPosition + 1) % items.length;\n}\navailableItems.release();\n}\n\npublic E take() throws InterruptedException {\navailableItems.acquire();\nE item;\nsynchronized (this) {\nitem = items[takePosition];\nitems[takePosition] = null;\ntakePosition = (takePosition + 1) % items.length;\n}\navailableSpaces.release();\nreturn item;\n}\n\npublic static void main(String[] args) {\nfinal int bufferSize = 2;\nfinal int numItems = 2;\n\nSemaphoreBoundedBuffer<Integer> buffer = new SemaphoreBoundedBuffer<>(bufferSize);\n\nThread producer = new Thread(() -> {\ntry {\nfor (int i = 0; i < numItems; i++) {\nbuffer.put(i);\n// Avoid printing to reduce state space\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n\nThread consumer = new Thread(() -> {\ntry {\nfor (int i = 0; i < numItems; i++) {\nInteger item = buffer.take();\n// Avoid printing to reduce state space\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n\nproducer.start();\nconsumer.start();\n\ntry {\nproducer.join();\nconsumer.join();\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n\n// Minimal output\nSystem.out.println(\"Done.\");\n}\n}",
        "max_depth": "71",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.22%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 59.20%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.96%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=129676,visited=100037,backtracked=229101,end=195\nsearch:             maxDepth=710,constraints=45166\nchoice generators:  thread=86496 (signal=0,lock=21657,sharedRef=22421,threadApi=11345,reschedule=12774), data=0\nheap:               new=1246244,released=989305,maxLive=750,gcCycles=229713\ninstructions:       43429599\nmax memory:         1018MB\nloaded code:        classes=137,methods=2415\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.25%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.04%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.44%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=115564,visited=152826,backtracked=267750,end=66\nsearch:             maxDepth=710,constraints=27027\nchoice generators:  thread=93993 (signal=0,lock=13375,sharedRef=55714,threadApi=8059,reschedule=10135), data=0\nheap:               new=499833,released=996056,maxLive=779,gcCycles=268390\ninstructions:       38760954\nmax memory:         1019MB\nloaded code:        classes=142,methods=2442\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.53%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.17%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=198592,visited=78202,backtracked=276107,end=0\nsearch:             maxDepth=710,constraints=118780\nchoice generators:  thread=95243 (signal=0,lock=8556,sharedRef=53855,threadApi=3874,reschedule=2106), data=0\nheap:               new=321571,released=386345,maxLive=778,gcCycles=276794\ninstructions:       21743099\nmax memory:         1018MB\nloaded code:        classes=139,methods=2426\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            56.79,
            58.25,
            55.34
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Potion {\n    private final String name;\n    private final int strength;\n\n    public Potion(String name, int strength) {\n        this.name = name;\n        this.strength = strength;\n    }\n\n    @Override\n    public String toString() {\n        return name + \" (strength: \" + strength + \")\";\n    }\n}\n\nclass PotionLoop {\n    private final Potion[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availablePotions;\n    private final Semaphore availableSlots;\n    private final Object lock;\n\n    public PotionLoop(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Potion[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availablePotions = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n\n    public void put(Potion potion) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = potion;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availablePotions.release();\n    }\n\n    public Potion take() throws InterruptedException {\n        availablePotions.acquire();\n        Potion potion;\n        synchronized (lock) {\n            potion = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        availableSlots.release();\n        return potion;\n    }\n\n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n\n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Alchemist implements Runnable {\n    private final PotionLoop loop;\n    private final String name;\n    private final boolean isProducer;\n\n    public Alchemist(PotionLoop loop, String name, boolean isProducer) {\n        this.loop = loop;\n        this.name = name;\n        this.isProducer = isProducer;\n    }\n\n    @Override\n    public void run() {\n        try {\n            if (isProducer) {\n                for (int i = 0; i < 3; i++) {\n                    Potion potion = new Potion(name + \"-Potion-\" + i, i * 10);\n                    System.out.println(name + \" creating \" + potion);\n                    loop.put(potion);\n                    System.out.println(name + \" added \" + potion);\n                    Thread.sleep(100);\n                }\n            } else {\n                for (int i = 0; i < 3; i++) {\n                    System.out.println(name + \" waiting for potion...\");\n                    Potion potion = loop.take();\n                    System.out.println(name + \" extracted \" + potion);\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class PotionLoopDemo {\n    public static void main(String[] args) {\n        PotionLoop loop = new PotionLoop(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.execute(new Alchemist(loop, \"Producer-Alchemist\", true));\n        executor.execute(new Alchemist(loop, \"Consumer-Alchemist\", false));\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Loop is empty: \" + loop.isEmpty());\n        System.out.println(\"Loop is full: \" + loop.isFull());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Potion {\n    private final String name;\n    private final int strength;\n    \n    public Potion(String name, int strength) {\n        this.name = name;\n        this.strength = strength;\n    }\n    \n    @Override\n    public String toString() {\n        return name + \" (strength: \" + strength + \")\";\n    }\n}\n\nclass PotionLoop {\n    private final Potion[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore available;\n    private final Semaphore spaces;\n    private final Object lock;\n    \n    public PotionLoop(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Potion[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.available = new Semaphore(0);\n        this.spaces = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n    \n    public void put(Potion x) throws InterruptedException {\n        spaces.acquire();\n        synchronized (lock) {\n            buffer[tail] = x;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        available.release();\n    }\n    \n    public Potion take() throws InterruptedException {\n        available.acquire();\n        Potion potion;\n        synchronized (lock) {\n            potion = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        spaces.release();\n        return potion;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\nclass Alchemist implements Runnable {\n    private final PotionLoop loop;\n    private final boolean isProducer;\n    private final int id;\n    \n    public Alchemist(PotionLoop loop, boolean isProducer, int id) {\n        this.loop = loop;\n        this.isProducer = isProducer;\n        this.id = id;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            for (int i = 0; i < 3; i++) {\n                if (isProducer) {\n                    Potion potion = new Potion(\"Potion-\" + id + \"-\" + i, (id + 1) * 10 + i);\n                    System.out.println(\"Alchemist \" + id + \" creating: \" + potion);\n                    loop.put(potion);\n                    System.out.println(\"Alchemist \" + id + \" added: \" + potion);\n                    Thread.sleep(100);\n                } else {\n                    Potion potion = loop.take();\n                    System.out.println(\"Alchemist \" + id + \" extracted: \" + potion);\n                    Thread.sleep(150);\n                }\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class PotionLoopDemo {\n    public static void main(String[] args) {\n        PotionLoop loop = new PotionLoop(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(new Alchemist(loop, true, 1));\n        executor.submit(new Alchemist(loop, false, 2));\n        \n        try {\n            Thread.sleep(500);\n            \n            loop.put(new Potion(\"HealthPotion\", 50));\n            loop.put(new Potion(\"ManaPotion\", 30));\n            \n            System.out.println(\"Is loop empty? \" + loop.isEmpty());\n            System.out.println(\"Is loop full? \" + loop.isFull());\n            \n            Potion taken = loop.take();\n            System.out.println(\"Main thread took: \" + taken);\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(2, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass Potion {\n    private final String name;\n    private final int power;\n\n    public Potion(String name, int power) {\n        this.name = name;\n        this.power = power;\n    }\n\n    @Override\n    public String toString() {\n        return \"Potion{name='\" + name + \"', power=\" + power + \"}\";\n    }\n}\n\nclass PotionLoop {\n    private final Potion[] buffer;\n    private final int capacity;\n    private int head;\n    private int tail;\n    private int count;\n    private final Semaphore availablePotions;\n    private final Semaphore availableSlots;\n    private final Object lock;\n\n    public PotionLoop(int capacity) {\n        this.capacity = capacity;\n        this.buffer = new Potion[capacity];\n        this.head = 0;\n        this.tail = 0;\n        this.count = 0;\n        this.availablePotions = new Semaphore(0);\n        this.availableSlots = new Semaphore(capacity);\n        this.lock = new Object();\n    }\n\n    public void put(Potion x) throws InterruptedException {\n        availableSlots.acquire();\n        synchronized (lock) {\n            buffer[tail] = x;\n            tail = (tail + 1) % capacity;\n            count++;\n        }\n        availablePotions.release();\n    }\n\n    public Potion take() throws InterruptedException {\n        availablePotions.acquire();\n        Potion potion;\n        synchronized (lock) {\n            potion = buffer[head];\n            buffer[head] = null;\n            head = (head + 1) % capacity;\n            count--;\n        }\n        availableSlots.release();\n        return potion;\n    }\n\n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n\n    public boolean isFull() {\n        synchronized (lock) {\n            return count == capacity;\n        }\n    }\n}\n\npublic class PotionLoopDemo {\n    public static void main(String[] args) {\n        PotionLoop potionLoop = new PotionLoop(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Potion potion = new Potion(\"Healing-\" + i, 10 + i);\n                    System.out.println(\"Producer adding: \" + potion);\n                    potionLoop.put(potion);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Potion potion = potionLoop.take();\n                    System.out.println(\"Consumer took: \" + potion);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Wrapping a Map with a read-write lock. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called CrystalCache that wraps a standard Map of enchanted relics and provides thread-safe access using a read-write lock enchantment. The class should allow multiple seers or a single enchanter at any given time. Use ReentrantReadWriteLock from the java.util.concurrent.locks package to govern access. For all write rituals (put, remove, putAll, clear), acquire the write lock, and for all read rituals (get, size, isEmpty, containsKey, containsValue), acquire the read lock. Ensure that locks are always released after each ritual using try-finally blocks. The constructor should accept an existing Map of relics to wrap. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass CrystalCache<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public CrystalCache(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public void put(K key, V value) {\n        writeLock.lock();\n        try {\n            map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void remove(K key) {\n        writeLock.lock();\n        try {\n            map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Integer> initialMap = new HashMap<>();\n        initialMap.put(\"relic1\", 100);\n        initialMap.put(\"relic2\", 200);\n        \n        CrystalCache<String, Integer> cache = new CrystalCache<>(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                cache.put(\"enchanted_\" + i, i * 10);\n                System.out.println(\"Writer added enchanted_\" + i);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = cache.get(\"relic1\");\n                System.out.println(\"Reader1 read relic1: \" + value);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int size = cache.size();\n                System.out.println(\"Reader2 cache size: \" + size);\n                try {\n                    Thread.sleep(75);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class CrystalCache<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public CrystalCache(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> relics = new HashMap<>();\n        CrystalCache<String, Integer> cache = new CrystalCache<>(relics);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                cache.put(\"relic\" + i, i * 100);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = cache.get(\"relic\" + i);\n                System.out.println(\"Read: relic\" + i + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int size = cache.size();\n                System.out.println(\"Cache size: \" + size);\n                boolean contains = cache.containsKey(\"relic\" + i);\n                System.out.println(\"Contains relic\" + i + \": \" + contains);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final cache size: \" + cache.size());\n        for (int i = 0; i < 10; i++) {\n            System.out.println(\"relic\" + i + \" = \" + cache.get(\"relic\" + i));\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class CrystalCache<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public CrystalCache(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> relics = new HashMap<>();\n        CrystalCache<String, Integer> cache = new CrystalCache<>(relics);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                cache.put(\"relic\" + i, i * 100);\n                System.out.println(Thread.currentThread().getName() + \" put relic\" + i + \" = \" + (i * 100));\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 15; i++) {\n                Integer value = cache.get(\"relic\" + (i % 10));\n                System.out.println(Thread.currentThread().getName() + \" read relic\" + (i % 10) + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 15; i++) {\n                boolean contains = cache.containsKey(\"relic\" + (i % 10));\n                System.out.println(Thread.currentThread().getName() + \" contains relic\" + (i % 10) + \" = \" + contains);\n                int size = cache.size();\n                System.out.println(Thread.currentThread().getName() + \" cache size = \" + size);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n\n        System.out.println(\"Final cache size: \" + cache.size());\n        for (int i = 0; i < 10; i++) {\n            System.out.println(\"relic\" + i + \" = \" + cache.get(\"relic\" + i));\n        }\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.HashMap;\nimport java.util.Map;\n\npublic class SimpleReadWriteMap<K, V> {\nprivate final Map<K, V> map = new HashMap<>();\n\npublic synchronized V put(K key, V value) {\nreturn map.put(key, value);\n}\n\npublic synchronized V get(Object key) {\nreturn map.get(key);\n}\n\npublic synchronized int size() {\nreturn map.size();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal SimpleReadWriteMap<String, String> rwMap = new SimpleReadWriteMap<>();\n\nThread writer = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nrwMap.put(\"key\" + i, \"value\" + i);\nSystem.out.println(\"Writer wrote: key\" + i);\n}\n}\n});\n\nThread reader1 = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nString val = rwMap.get(\"key\" + i);\nif (val != null) {\nSystem.out.println(\"Reader1 read: \" + val);\n}\n}\n}\n});\n\nThread reader2 = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nString val = rwMap.get(\"key\" + i);\nif (val != null) {\nSystem.out.println(\"Reader2 read: \" + val);\n}\n}\n}\n});\n\nwriter.start();\nreader1.start();\nreader2.start();\n\nwriter.join();\nreader1.join();\nreader2.join();\n\nSystem.out.println(\"Final size: \" + rwMap.size());\n}\n}",
        "max_depth": "98",
        "jpf_details": [
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=768,released=0,maxLive=0,gcCycles=0\ninstructions:       6676\nmax memory:         981MB\nloaded code:        classes=91,methods=1752\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=491,released=0,maxLive=0,gcCycles=0\ninstructions:       6422\nmax memory:         981MB\nloaded code:        classes=89,methods=1744\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=491,released=0,maxLive=0,gcCycles=0\ninstructions:       6422\nmax memory:         981MB\nloaded code:        classes=89,methods=1744\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\""
        ],
        "codebleu_score": [
            57.54,
            60.53,
            57.89
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass CrystalCache<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public CrystalCache(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public void put(K key, V value) {\n        writeLock.lock();\n        try {\n            map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void remove(K key) {\n        writeLock.lock();\n        try {\n            map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Integer> initialMap = new HashMap<>();\n        initialMap.put(\"relic1\", 100);\n        initialMap.put(\"relic2\", 200);\n        \n        CrystalCache<String, Integer> cache = new CrystalCache<>(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                cache.put(\"enchanted_\" + i, i * 10);\n                System.out.println(\"Writer added enchanted_\" + i);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = cache.get(\"relic1\");\n                System.out.println(\"Reader1 read relic1: \" + value);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int size = cache.size();\n                System.out.println(\"Reader2 cache size: \" + size);\n                try {\n                    Thread.sleep(75);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class CrystalCache<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public CrystalCache(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> relics = new HashMap<>();\n        CrystalCache<String, Integer> cache = new CrystalCache<>(relics);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                cache.put(\"relic\" + i, i * 100);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = cache.get(\"relic\" + i);\n                System.out.println(\"Read: relic\" + i + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int size = cache.size();\n                System.out.println(\"Cache size: \" + size);\n                boolean contains = cache.containsKey(\"relic\" + i);\n                System.out.println(\"Contains relic\" + i + \": \" + contains);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final cache size: \" + cache.size());\n        for (int i = 0; i < 10; i++) {\n            System.out.println(\"relic\" + i + \" = \" + cache.get(\"relic\" + i));\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class CrystalCache<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public CrystalCache(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> relics = new HashMap<>();\n        CrystalCache<String, Integer> cache = new CrystalCache<>(relics);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                cache.put(\"relic\" + i, i * 100);\n                System.out.println(Thread.currentThread().getName() + \" put relic\" + i + \" = \" + (i * 100));\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 15; i++) {\n                Integer value = cache.get(\"relic\" + (i % 10));\n                System.out.println(Thread.currentThread().getName() + \" read relic\" + (i % 10) + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 15; i++) {\n                boolean contains = cache.containsKey(\"relic\" + (i % 10));\n                System.out.println(Thread.currentThread().getName() + \" contains relic\" + (i % 10) + \" = \" + contains);\n                int size = cache.size();\n                System.out.println(Thread.currentThread().getName() + \" cache size = \" + size);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n\n        System.out.println(\"Final cache size: \" + cache.size());\n        for (int i = 0; i < 10; i++) {\n            System.out.println(\"relic\" + i + \" = \" + cache.get(\"relic\" + i));\n        }\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Wrapping a Map with a read-write lock. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called SigilLedger that wraps a standard Map of mystical runes and provides thread-safe access using a read-write lock charm. The class should allow multiple diviners or a single inscriber at any given time. Use ReentrantReadWriteLock from the java.util.concurrent.locks package to regulate access. For all write incantations (put, remove, putAll, clear), acquire the write lock, and for all read incantations (get, size, isEmpty, containsKey, containsValue), acquire the read lock. Ensure that locks are always released after each incantation using try-finally blocks. The constructor should accept an existing Map of runes to wrap. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class SigilLedger<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public SigilLedger(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) {\n        Map<String, Integer> baseMap = new HashMap<>();\n        SigilLedger<String, Integer> ledger = new SigilLedger<>(baseMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                ledger.put(\"rune\" + i, i * 10);\n                System.out.println(\"Writer 1: Added rune\" + i + \" = \" + (i * 10));\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = ledger.get(\"rune\" + i);\n                System.out.println(\"Reader 1: rune\" + i + \" = \" + value);\n                try {\n                    Thread.sleep(70);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                boolean contains = ledger.containsKey(\"rune\" + i);\n                int size = ledger.size();\n                System.out.println(\"Reader 2: Contains rune\" + i + \"? \" + contains + \", Size: \" + size);\n                try {\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Final ledger size: \" + ledger.size());\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass SigilLedger<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public SigilLedger(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Integer> baseMap = new HashMap<>();\n        SigilLedger<String, Integer> ledger = new SigilLedger<>(baseMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                ledger.put(\"rune\" + i, i * 10);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 20; i++) {\n                Integer value = ledger.get(\"rune\" + (i % 10));\n                System.out.println(\"Reader 1 read: rune\" + (i % 10) + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 20; i++) {\n                boolean contains = ledger.containsKey(\"rune\" + (i % 10));\n                System.out.println(\"Reader 2 check: rune\" + (i % 10) + \" exists = \" + contains);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Final ledger size: \" + ledger.size());\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class SigilLedger<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public SigilLedger(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> baseMap = new HashMap<>();\n        SigilLedger<String, Integer> ledger = new SigilLedger<>(baseMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                ledger.put(\"rune\" + i, i * 10);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 20; i++) {\n                Integer value = ledger.get(\"rune\" + (i % 10));\n                System.out.println(\"Reader 1: rune\" + (i % 10) + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 20; i++) {\n                boolean contains = ledger.containsKey(\"rune\" + (i % 10));\n                System.out.println(\"Reader 2: contains rune\" + (i % 10) + \" = \" + contains);\n                int size = ledger.size();\n                System.out.println(\"Reader 2: size = \" + size);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.HashMap;\nimport java.util.Map;\n\npublic class SimpleReadWriteMap<K, V> {\nprivate final Map<K, V> map = new HashMap<>();\n\npublic synchronized V put(K key, V value) {\nreturn map.put(key, value);\n}\n\npublic synchronized V get(Object key) {\nreturn map.get(key);\n}\n\npublic synchronized int size() {\nreturn map.size();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal SimpleReadWriteMap<String, String> rwMap = new SimpleReadWriteMap<>();\n\nThread writer = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nrwMap.put(\"key\" + i, \"value\" + i);\nSystem.out.println(\"Writer wrote: key\" + i);\n}\n}\n});\n\nThread reader1 = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nString val = rwMap.get(\"key\" + i);\nif (val != null) {\nSystem.out.println(\"Reader1 read: \" + val);\n}\n}\n}\n});\n\nThread reader2 = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nString val = rwMap.get(\"key\" + i);\nif (val != null) {\nSystem.out.println(\"Reader2 read: \" + val);\n}\n}\n}\n});\n\nwriter.start();\nreader1.start();\nreader2.start();\n\nwriter.join();\nreader1.join();\nreader2.join();\n\nSystem.out.println(\"Final size: \" + rwMap.size());\n}\n}",
        "max_depth": "98",
        "jpf_details": [
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=491,released=0,maxLive=0,gcCycles=0\ninstructions:       6422\nmax memory:         981MB\nloaded code:        classes=89,methods=1744\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=494,released=0,maxLive=0,gcCycles=0\ninstructions:       6422\nmax memory:         981MB\nloaded code:        classes=90,methods=1745\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=491,released=0,maxLive=0,gcCycles=0\ninstructions:       6422\nmax memory:         981MB\nloaded code:        classes=89,methods=1744\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\""
        ],
        "codebleu_score": [
            58.23,
            54.43,
            56.99
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class SigilLedger<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public SigilLedger(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) {\n        Map<String, Integer> baseMap = new HashMap<>();\n        SigilLedger<String, Integer> ledger = new SigilLedger<>(baseMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                ledger.put(\"rune\" + i, i * 10);\n                System.out.println(\"Writer 1: Added rune\" + i + \" = \" + (i * 10));\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = ledger.get(\"rune\" + i);\n                System.out.println(\"Reader 1: rune\" + i + \" = \" + value);\n                try {\n                    Thread.sleep(70);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                boolean contains = ledger.containsKey(\"rune\" + i);\n                int size = ledger.size();\n                System.out.println(\"Reader 2: Contains rune\" + i + \"? \" + contains + \", Size: \" + size);\n                try {\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Final ledger size: \" + ledger.size());\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass SigilLedger<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public SigilLedger(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Integer> baseMap = new HashMap<>();\n        SigilLedger<String, Integer> ledger = new SigilLedger<>(baseMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                ledger.put(\"rune\" + i, i * 10);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 20; i++) {\n                Integer value = ledger.get(\"rune\" + (i % 10));\n                System.out.println(\"Reader 1 read: rune\" + (i % 10) + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 20; i++) {\n                boolean contains = ledger.containsKey(\"rune\" + (i % 10));\n                System.out.println(\"Reader 2 check: rune\" + (i % 10) + \" exists = \" + contains);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Final ledger size: \" + ledger.size());\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class SigilLedger<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public SigilLedger(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> baseMap = new HashMap<>();\n        SigilLedger<String, Integer> ledger = new SigilLedger<>(baseMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                ledger.put(\"rune\" + i, i * 10);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 20; i++) {\n                Integer value = ledger.get(\"rune\" + (i % 10));\n                System.out.println(\"Reader 1: rune\" + (i % 10) + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 20; i++) {\n                boolean contains = ledger.containsKey(\"rune\" + (i % 10));\n                System.out.println(\"Reader 2: contains rune\" + (i % 10) + \" = \" + contains);\n                int size = ledger.size();\n                System.out.println(\"Reader 2: size = \" + size);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Wrapping a Map with a read-write lock. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called EnchantedRegistry that wraps a standard Map of arcane artifacts and provides thread-safe access using a read-write lock spell. The class should allow multiple observers or a single crafter at any given time. Use ReentrantReadWriteLock from the java.util.concurrent.locks package to control access. For all write operations (put, remove, putAll, clear), acquire the write lock, and for all read operations (get, size, isEmpty, containsKey, containsValue), acquire the read lock. Ensure that locks are always released after each operation using try-finally blocks. The constructor should accept an existing Map of artifacts to wrap. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass ArcaneArtifact {\n    private final String name;\n    private final int power;\n    \n    public ArcaneArtifact(String name, int power) {\n        this.name = name;\n        this.power = power;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getPower() {\n        return power;\n    }\n    \n    @Override\n    public String toString() {\n        return \"ArcaneArtifact{name='\" + name + \"', power=\" + power + \"}\";\n    }\n}\n\nclass EnchantedRegistry<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n    \n    public EnchantedRegistry(Map<K, V> map) {\n        this.map = map;\n    }\n    \n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n    \n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n    \n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n    \n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n}\n\npublic class MagicalArtifactManager {\n    \n    public static void main(String[] args) {\n        Map<String, ArcaneArtifact> initialMap = new HashMap<>();\n        initialMap.put(\"Wand\", new ArcaneArtifact(\"Elder Wand\", 100));\n        initialMap.put(\"Stone\", new ArcaneArtifact(\"Philosopher's Stone\", 90));\n        \n        EnchantedRegistry<String, ArcaneArtifact> registry = new EnchantedRegistry<>(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                ArcaneArtifact artifact = registry.get(\"Wand\");\n                System.out.println(\"Observer 1 read: \" + artifact);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                System.out.println(\"Observer 2 - Registry size: \" + registry.size());\n                System.out.println(\"Observer 2 - Contains Stone: \" + registry.containsKey(\"Stone\"));\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            \n            registry.put(\"Ring\", new ArcaneArtifact(\"One Ring\", 95));\n            System.out.println(\"Crafter added Ring\");\n            \n            try {\n                Thread.sleep(300);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            \n            Map<String, ArcaneArtifact> newArtifacts = new HashMap<>();\n            newArtifacts.put(\"Cloak\", new ArcaneArtifact(\"Invisibility Cloak\", 85));\n            newArtifacts.put(\"Sword\", new ArcaneArtifact(\"Excalibur\", 88));\n            registry.putAll(newArtifacts);\n            System.out.println(\"Crafter added multiple artifacts\");\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            \n            registry.remove(\"Stone\");\n            System.out.println(\"Crafter removed Stone\");\n        });\n        \n        executor.shutdown();\n        \n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final registry size: \" + registry.size());\n        System.out.println(\"Final registry is empty: \" + registry.isEmpty());\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass EnchantedRegistry<K, V> {\n    private final Map<K, V> artifacts;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public EnchantedRegistry(Map<K, V> artifacts) {\n        this.artifacts = artifacts;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return artifacts.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return artifacts.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return artifacts.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return artifacts.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return artifacts.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return artifacts.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return artifacts.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> map) {\n        writeLock.lock();\n        try {\n            artifacts.putAll(map);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            artifacts.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> initialMap = new HashMap<>();\n        initialMap.put(\"Wand\", 100);\n        initialMap.put(\"Potion\", 50);\n        \n        EnchantedRegistry<String, Integer> registry = new EnchantedRegistry<>(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                registry.put(\"Artifact\" + i, i * 10);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = registry.get(\"Wand\");\n                System.out.println(\"Read Wand: \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int size = registry.size();\n                System.out.println(\"Registry size: \" + size);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final registry size: \" + registry.size());\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class EnchantedRegistry<K, V> {\n    private final Map<K, V> artifacts;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public EnchantedRegistry(Map<K, V> artifacts) {\n        this.artifacts = artifacts;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return artifacts.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return artifacts.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return artifacts.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return artifacts.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return artifacts.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return artifacts.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return artifacts.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> map) {\n        writeLock.lock();\n        try {\n            artifacts.putAll(map);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            artifacts.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) {\n        Map<String, Integer> initialMap = new HashMap<>();\n        initialMap.put(\"Wand\", 100);\n        initialMap.put(\"Potion\", 50);\n        initialMap.put(\"Scroll\", 75);\n\n        EnchantedRegistry<String, Integer> registry = new EnchantedRegistry<>(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                registry.put(\"Item\" + i, i * 10);\n                System.out.println(\"Writer added Item\" + i + \" with value \" + (i * 10));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = registry.get(\"Wand\");\n                System.out.println(\"Reader 1 read Wand: \" + value);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int size = registry.size();\n                System.out.println(\"Reader 2 registry size: \" + size);\n                try {\n                    Thread.sleep(75);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Final registry size: \" + registry.size());\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.HashMap;\nimport java.util.Map;\n\npublic class SimpleReadWriteMap<K, V> {\nprivate final Map<K, V> map = new HashMap<>();\n\npublic synchronized V put(K key, V value) {\nreturn map.put(key, value);\n}\n\npublic synchronized V get(Object key) {\nreturn map.get(key);\n}\n\npublic synchronized int size() {\nreturn map.size();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal SimpleReadWriteMap<String, String> rwMap = new SimpleReadWriteMap<>();\n\nThread writer = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nrwMap.put(\"key\" + i, \"value\" + i);\nSystem.out.println(\"Writer wrote: key\" + i);\n}\n}\n});\n\nThread reader1 = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nString val = rwMap.get(\"key\" + i);\nif (val != null) {\nSystem.out.println(\"Reader1 read: \" + val);\n}\n}\n}\n});\n\nThread reader2 = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nString val = rwMap.get(\"key\" + i);\nif (val != null) {\nSystem.out.println(\"Reader2 read: \" + val);\n}\n}\n}\n});\n\nwriter.start();\nreader1.start();\nreader2.start();\n\nwriter.join();\nreader1.join();\nreader2.join();\n\nSystem.out.println(\"Final size: \" + rwMap.size());\n}\n}",
        "max_depth": "98",
        "jpf_details": [
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=516,released=0,maxLive=0,gcCycles=0\ninstructions:       6698\nmax memory:         981MB\nloaded code:        classes=92,methods=1756\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=767,released=0,maxLive=0,gcCycles=0\ninstructions:       6676\nmax memory:         981MB\nloaded code:        classes=91,methods=1752\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=767,released=0,maxLive=0,gcCycles=0\ninstructions:       6784\nmax memory:         981MB\nloaded code:        classes=90,methods=1751\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\""
        ],
        "codebleu_score": [
            62.7,
            58.95,
            59.13
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass ArcaneArtifact {\n    private final String name;\n    private final int power;\n    \n    public ArcaneArtifact(String name, int power) {\n        this.name = name;\n        this.power = power;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getPower() {\n        return power;\n    }\n    \n    @Override\n    public String toString() {\n        return \"ArcaneArtifact{name='\" + name + \"', power=\" + power + \"}\";\n    }\n}\n\nclass EnchantedRegistry<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n    \n    public EnchantedRegistry(Map<K, V> map) {\n        this.map = map;\n    }\n    \n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n    \n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n    \n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n    \n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n    \n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n}\n\npublic class MagicalArtifactManager {\n    \n    public static void main(String[] args) {\n        Map<String, ArcaneArtifact> initialMap = new HashMap<>();\n        initialMap.put(\"Wand\", new ArcaneArtifact(\"Elder Wand\", 100));\n        initialMap.put(\"Stone\", new ArcaneArtifact(\"Philosopher's Stone\", 90));\n        \n        EnchantedRegistry<String, ArcaneArtifact> registry = new EnchantedRegistry<>(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                ArcaneArtifact artifact = registry.get(\"Wand\");\n                System.out.println(\"Observer 1 read: \" + artifact);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                System.out.println(\"Observer 2 - Registry size: \" + registry.size());\n                System.out.println(\"Observer 2 - Contains Stone: \" + registry.containsKey(\"Stone\"));\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            \n            registry.put(\"Ring\", new ArcaneArtifact(\"One Ring\", 95));\n            System.out.println(\"Crafter added Ring\");\n            \n            try {\n                Thread.sleep(300);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            \n            Map<String, ArcaneArtifact> newArtifacts = new HashMap<>();\n            newArtifacts.put(\"Cloak\", new ArcaneArtifact(\"Invisibility Cloak\", 85));\n            newArtifacts.put(\"Sword\", new ArcaneArtifact(\"Excalibur\", 88));\n            registry.putAll(newArtifacts);\n            System.out.println(\"Crafter added multiple artifacts\");\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            \n            registry.remove(\"Stone\");\n            System.out.println(\"Crafter removed Stone\");\n        });\n        \n        executor.shutdown();\n        \n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final registry size: \" + registry.size());\n        System.out.println(\"Final registry is empty: \" + registry.isEmpty());\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass EnchantedRegistry<K, V> {\n    private final Map<K, V> artifacts;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public EnchantedRegistry(Map<K, V> artifacts) {\n        this.artifacts = artifacts;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return artifacts.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return artifacts.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return artifacts.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return artifacts.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return artifacts.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return artifacts.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return artifacts.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> map) {\n        writeLock.lock();\n        try {\n            artifacts.putAll(map);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            artifacts.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> initialMap = new HashMap<>();\n        initialMap.put(\"Wand\", 100);\n        initialMap.put(\"Potion\", 50);\n        \n        EnchantedRegistry<String, Integer> registry = new EnchantedRegistry<>(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                registry.put(\"Artifact\" + i, i * 10);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = registry.get(\"Wand\");\n                System.out.println(\"Read Wand: \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int size = registry.size();\n                System.out.println(\"Registry size: \" + size);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final registry size: \" + registry.size());\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\npublic class EnchantedRegistry<K, V> {\n    private final Map<K, V> artifacts;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public EnchantedRegistry(Map<K, V> artifacts) {\n        this.artifacts = artifacts;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return artifacts.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return artifacts.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return artifacts.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return artifacts.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return artifacts.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return artifacts.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return artifacts.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> map) {\n        writeLock.lock();\n        try {\n            artifacts.putAll(map);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            artifacts.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public static void main(String[] args) {\n        Map<String, Integer> initialMap = new HashMap<>();\n        initialMap.put(\"Wand\", 100);\n        initialMap.put(\"Potion\", 50);\n        initialMap.put(\"Scroll\", 75);\n\n        EnchantedRegistry<String, Integer> registry = new EnchantedRegistry<>(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                registry.put(\"Item\" + i, i * 10);\n                System.out.println(\"Writer added Item\" + i + \" with value \" + (i * 10));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = registry.get(\"Wand\");\n                System.out.println(\"Reader 1 read Wand: \" + value);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int size = registry.size();\n                System.out.println(\"Reader 2 registry size: \" + size);\n                try {\n                    Thread.sleep(75);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Final registry size: \" + registry.size());\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Simulated CAS operation. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class called MysticCounter that simulates the behavior of an Arcane Compare-and-Swap (CAS) ritual, commonly used in concurrent spellcraft for atomic enchantments. The class should maintain an internal integer essence and provide thread-safe incantations to interact with it. \n\nThe class should include: \n\nA private integer field essence to store the current magical value. \nA synchronized get() method that reveals the current essence. \nA synchronized compareAndSwap(int expectedEssence, int newEssence) method that checks if the current essence matches the expectedEssence. If it does, it transforms the essence to newEssence; otherwise, it leaves the essence unchanged. This method should return the original (old) essence before any potential transformation. \nA synchronized compareAndSet(int expectedEssence, int newEssence) method that uses compareAndSwap() to determine whether the essence was successfully transformed. It should return true if the essence was changed (i.e., if the old essence matched the expected essence), and false otherwise. \n\nEnsure that all methods are thread-safe using the synchronized keyword to prevent collisions of magical energy when accessed by multiple threads concurrently. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticCounter {\n    private int essence;\n    \n    public MysticCounter() {\n        this.essence = 0;\n    }\n    \n    public MysticCounter(int initialEssence) {\n        this.essence = initialEssence;\n    }\n    \n    public synchronized int get() {\n        return essence;\n    }\n    \n    public synchronized int compareAndSwap(int expectedEssence, int newEssence) {\n        int oldEssence = essence;\n        if (essence == expectedEssence) {\n            essence = newEssence;\n        }\n        return oldEssence;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedEssence, int newEssence) {\n        int oldEssence = compareAndSwap(expectedEssence, newEssence);\n        return oldEssence == expectedEssence;\n    }\n    \n    public static void main(String[] args) {\n        MysticCounter counter = new MysticCounter(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 1) + \", success: \" + success);\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                int oldValue = counter.compareAndSwap(current, current + 10);\n                System.out.println(\"Thread 2: compareAndSwap expected \" + current + \", old value was \" + oldValue + \", new value: \" + counter.get());\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        \n        for (int i = 0; i < 5; i++) {\n            int current = counter.get();\n            boolean success = counter.compareAndSet(current, current + 100);\n            System.out.println(\"Main thread: Attempted to change \" + current + \" to \" + (current + 100) + \", success: \" + success);\n            try {\n                Thread.sleep(20);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final essence value: \" + counter.get());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass MysticCounter {\n    private int essence;\n    \n    public MysticCounter() {\n        this.essence = 0;\n    }\n    \n    public MysticCounter(int initialEssence) {\n        this.essence = initialEssence;\n    }\n    \n    public synchronized int get() {\n        return essence;\n    }\n    \n    public synchronized int compareAndSwap(int expectedEssence, int newEssence) {\n        int oldEssence = essence;\n        if (essence == expectedEssence) {\n            essence = newEssence;\n        }\n        return oldEssence;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedEssence, int newEssence) {\n        int oldEssence = compareAndSwap(expectedEssence, newEssence);\n        return oldEssence == expectedEssence;\n    }\n}\n\npublic class MysticCounterDemo {\n    public static void main(String[] args) {\n        MysticCounter counter = new MysticCounter(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 1) + \", Success: \" + success);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 10; i++) {\n            int current = counter.get();\n            boolean success = counter.compareAndSet(current, current + 2);\n            System.out.println(\"Main Thread: Attempted to change \" + current + \" to \" + (current + 2) + \", Success: \" + success);\n            try {\n                Thread.sleep(30);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final essence value: \" + counter.get());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticCounter {\n    private int essence;\n    \n    public MysticCounter() {\n        this.essence = 0;\n    }\n    \n    public MysticCounter(int initialEssence) {\n        this.essence = initialEssence;\n    }\n    \n    public synchronized int get() {\n        return essence;\n    }\n    \n    public synchronized int compareAndSwap(int expectedEssence, int newEssence) {\n        int oldEssence = essence;\n        if (essence == expectedEssence) {\n            essence = newEssence;\n        }\n        return oldEssence;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedEssence, int newEssence) {\n        int oldEssence = compareAndSwap(expectedEssence, newEssence);\n        return oldEssence == expectedEssence;\n    }\n    \n    public static void main(String[] args) {\n        MysticCounter counter = new MysticCounter(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 1) + \", success: \" + success);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 5; i++) {\n            int current = counter.get();\n            boolean success = counter.compareAndSet(current, current + 10);\n            System.out.println(\"Main thread: Attempted to change \" + current + \" to \" + (current + 10) + \", success: \" + success);\n            try {\n                Thread.sleep(150);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final essence value: \" + counter.get());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class SimulatedCAS {\nprivate int value;\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized int compareAndSwap(int expectedValue, int newValue) {\nint oldValue = value;\nif (oldValue == expectedValue) {\nvalue = newValue;\n}\nreturn oldValue;\n}\n\npublic synchronized boolean compareAndSet(int expectedValue, int newValue) {\nreturn expectedValue == compareAndSwap(expectedValue, newValue);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal SimulatedCAS cas = new SimulatedCAS();\n\n// Reduce number of threads and iterations for faster JPF analysis\nint threadCount = 2;\nint iterationsPerThread = 3;\n\nThread[] threads = new Thread[threadCount];\nfor (int i = 0; i < threadCount; i++) {\nfinal int threadId = i;\nthreads[i] = new Thread(new Runnable() {\npublic void run() {\nfor (int j = 0; j < iterationsPerThread; j++) {\nint expected;\ndo {\nexpected = cas.get();\n} while (!cas.compareAndSet(expected, expected + 1));\nSystem.out.println(Thread.currentThread().getName() + \" incremented to: \" + cas.get());\n}\n}\n}, \"Worker-\" + threadId);\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final value: \" + cas.get());\nSystem.out.println(\"Expected value: \" + (threadCount * iterationsPerThread));\n}\n}",
        "max_depth": "101",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.94%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.90%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=201290,visited=80638,backtracked=281047,end=5052\nsearch:             maxDepth=1010,constraints=57405\nchoice generators:  thread=143940 (signal=0,lock=69283,sharedRef=254,threadApi=34624,reschedule=5081), data=0\nheap:               new=825678,released=715766,maxLive=723,gcCycles=242717\ninstructions:       39706320\nmax memory:         1015MB\nloaded code:        classes=136,methods=2413\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.65%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=247206,visited=44314,backtracked=290957,end=1509\nsearch:             maxDepth=1010,constraints=100425\nchoice generators:  thread=146810 (signal=0,lock=61933,sharedRef=262,threadApi=30919,reschedule=1548), data=0\nheap:               new=611152,released=496756,maxLive=722,gcCycles=245167\ninstructions:       28326921\nmax memory:         1018MB\nloaded code:        classes=137,methods=2412\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.77%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=260745,visited=31572,backtracked=291307,end=2015\nsearch:             maxDepth=1010,constraints=113079\nchoice generators:  thread=147679 (signal=0,lock=57315,sharedRef=158,threadApi=28638,reschedule=2038), data=0\nheap:               new=534709,released=490017,maxLive=719,gcCycles=246756\ninstructions:       25592915\nmax memory:         1017MB\nloaded code:        classes=136,methods=2411\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            63.35,
            62.19,
            62.19
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticCounter {\n    private int essence;\n    \n    public MysticCounter() {\n        this.essence = 0;\n    }\n    \n    public MysticCounter(int initialEssence) {\n        this.essence = initialEssence;\n    }\n    \n    public synchronized int get() {\n        return essence;\n    }\n    \n    public synchronized int compareAndSwap(int expectedEssence, int newEssence) {\n        int oldEssence = essence;\n        if (essence == expectedEssence) {\n            essence = newEssence;\n        }\n        return oldEssence;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedEssence, int newEssence) {\n        int oldEssence = compareAndSwap(expectedEssence, newEssence);\n        return oldEssence == expectedEssence;\n    }\n    \n    public static void main(String[] args) {\n        MysticCounter counter = new MysticCounter(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 1) + \", success: \" + success);\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                int oldValue = counter.compareAndSwap(current, current + 10);\n                System.out.println(\"Thread 2: compareAndSwap expected \" + current + \", old value was \" + oldValue + \", new value: \" + counter.get());\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        \n        for (int i = 0; i < 5; i++) {\n            int current = counter.get();\n            boolean success = counter.compareAndSet(current, current + 100);\n            System.out.println(\"Main thread: Attempted to change \" + current + \" to \" + (current + 100) + \", success: \" + success);\n            try {\n                Thread.sleep(20);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final essence value: \" + counter.get());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass MysticCounter {\n    private int essence;\n    \n    public MysticCounter() {\n        this.essence = 0;\n    }\n    \n    public MysticCounter(int initialEssence) {\n        this.essence = initialEssence;\n    }\n    \n    public synchronized int get() {\n        return essence;\n    }\n    \n    public synchronized int compareAndSwap(int expectedEssence, int newEssence) {\n        int oldEssence = essence;\n        if (essence == expectedEssence) {\n            essence = newEssence;\n        }\n        return oldEssence;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedEssence, int newEssence) {\n        int oldEssence = compareAndSwap(expectedEssence, newEssence);\n        return oldEssence == expectedEssence;\n    }\n}\n\npublic class MysticCounterDemo {\n    public static void main(String[] args) {\n        MysticCounter counter = new MysticCounter(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 1) + \", Success: \" + success);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 10; i++) {\n            int current = counter.get();\n            boolean success = counter.compareAndSet(current, current + 2);\n            System.out.println(\"Main Thread: Attempted to change \" + current + \" to \" + (current + 2) + \", Success: \" + success);\n            try {\n                Thread.sleep(30);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final essence value: \" + counter.get());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticCounter {\n    private int essence;\n    \n    public MysticCounter() {\n        this.essence = 0;\n    }\n    \n    public MysticCounter(int initialEssence) {\n        this.essence = initialEssence;\n    }\n    \n    public synchronized int get() {\n        return essence;\n    }\n    \n    public synchronized int compareAndSwap(int expectedEssence, int newEssence) {\n        int oldEssence = essence;\n        if (essence == expectedEssence) {\n            essence = newEssence;\n        }\n        return oldEssence;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedEssence, int newEssence) {\n        int oldEssence = compareAndSwap(expectedEssence, newEssence);\n        return oldEssence == expectedEssence;\n    }\n    \n    public static void main(String[] args) {\n        MysticCounter counter = new MysticCounter(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 1) + \", success: \" + success);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 5; i++) {\n            int current = counter.get();\n            boolean success = counter.compareAndSet(current, current + 10);\n            System.out.println(\"Main thread: Attempted to change \" + current + \" to \" + (current + 10) + \", success: \" + success);\n            try {\n                Thread.sleep(150);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final essence value: \" + counter.get());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Simulated CAS operation. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class called ArcaneGauge that simulates the behavior of a Compare-and-Swap (CAS) enchantment, commonly used in concurrent spellcraft for atomic updates. The class should maintain an internal integer mana level and provide thread-safe rituals to manipulate it. \n\nThe class should include: \n\nA private integer field mana to store the current magical value. A synchronized get() method that discloses the current mana. \nA synchronized compareAndSwap(int expectedMana, int newMana) method that checks if the current mana matches the expectedMana. If it does, it alters the mana to newMana; otherwise, it leaves the mana unchanged. This method should return the original (old) mana before any potential alteration. \nA synchronized compareAndSet(int expectedMana, int newMana) method that uses compareAndSwap() to determine whether the mana was successfully altered. It should return true if the mana was changed (i.e., if the old mana matched the expected mana), and false otherwise. \n\nEnsure that all methods are thread-safe using the synchronized keyword to prevent energy clashes when multiple threads access the mana concurrently. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ArcaneGauge {\n    private int mana;\n    \n    public ArcaneGauge(int initialMana) {\n        this.mana = initialMana;\n    }\n    \n    public synchronized int get() {\n        return mana;\n    }\n    \n    public synchronized int compareAndSwap(int expectedMana, int newMana) {\n        int oldMana = mana;\n        if (mana == expectedMana) {\n            mana = newMana;\n        }\n        return oldMana;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedMana, int newMana) {\n        return compareAndSwap(expectedMana, newMana) == expectedMana;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        ArcaneGauge gauge = new ArcaneGauge(100);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int current = gauge.get();\n                boolean success = gauge.compareAndSet(current, current + 10);\n                System.out.println(\"Thread 1: Attempted to increase mana from \" + current + \n                                 \" to \" + (current + 10) + \", success: \" + success);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 5; i++) {\n            int current = gauge.get();\n            boolean success = gauge.compareAndSet(current, current - 5);\n            System.out.println(\"Main Thread: Attempted to decrease mana from \" + current + \n                             \" to \" + (current - 5) + \", success: \" + success);\n            Thread.sleep(60);\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        System.out.println(\"Final mana level: \" + gauge.get());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ArcaneGauge {\n    private int mana;\n    \n    public ArcaneGauge(int initialMana) {\n        this.mana = initialMana;\n    }\n    \n    public synchronized int get() {\n        return mana;\n    }\n    \n    public synchronized int compareAndSwap(int expectedMana, int newMana) {\n        int oldMana = mana;\n        if (mana == expectedMana) {\n            mana = newMana;\n        }\n        return oldMana;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedMana, int newMana) {\n        int oldMana = compareAndSwap(expectedMana, newMana);\n        return oldMana == expectedMana;\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        ArcaneGauge gauge = new ArcaneGauge(100);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int current = gauge.get();\n                boolean success = gauge.compareAndSet(current, current + 10);\n                System.out.println(\"Thread 1 - Attempt \" + (i + 1) + \": \" + \n                    (success ? \"Success\" : \"Failed\") + \", New mana: \" + gauge.get());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 5; i++) {\n            int current = gauge.get();\n            boolean success = gauge.compareAndSet(current, current - 5);\n            System.out.println(\"Main Thread - Attempt \" + (i + 1) + \": \" + \n                (success ? \"Success\" : \"Failed\") + \", New mana: \" + gauge.get());\n            try {\n                Thread.sleep(150);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        System.out.println(\"Final mana level: \" + gauge.get());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ArcaneGauge {\n    private int mana;\n    \n    public ArcaneGauge(int initialMana) {\n        this.mana = initialMana;\n    }\n    \n    public synchronized int get() {\n        return mana;\n    }\n    \n    public synchronized int compareAndSwap(int expectedMana, int newMana) {\n        int oldMana = mana;\n        if (mana == expectedMana) {\n            mana = newMana;\n        }\n        return oldMana;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedMana, int newMana) {\n        return compareAndSwap(expectedMana, newMana) == expectedMana;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        ArcaneGauge gauge = new ArcaneGauge(100);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int current = gauge.get();\n                boolean success = gauge.compareAndSet(current, current + 10);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 10) + \", success: \" + success);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 5; i++) {\n            int current = gauge.get();\n            boolean success = gauge.compareAndSet(current, current - 5);\n            System.out.println(\"Main thread: Attempted to change \" + current + \" to \" + (current - 5) + \", success: \" + success);\n            Thread.sleep(60);\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        System.out.println(\"Final mana level: \" + gauge.get());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class SimulatedCAS {\nprivate int value;\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized int compareAndSwap(int expectedValue, int newValue) {\nint oldValue = value;\nif (oldValue == expectedValue) {\nvalue = newValue;\n}\nreturn oldValue;\n}\n\npublic synchronized boolean compareAndSet(int expectedValue, int newValue) {\nreturn expectedValue == compareAndSwap(expectedValue, newValue);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal SimulatedCAS cas = new SimulatedCAS();\n\n// Reduce number of threads and iterations for faster JPF analysis\nint threadCount = 2;\nint iterationsPerThread = 3;\n\nThread[] threads = new Thread[threadCount];\nfor (int i = 0; i < threadCount; i++) {\nfinal int threadId = i;\nthreads[i] = new Thread(new Runnable() {\npublic void run() {\nfor (int j = 0; j < iterationsPerThread; j++) {\nint expected;\ndo {\nexpected = cas.get();\n} while (!cas.compareAndSet(expected, expected + 1));\nSystem.out.println(Thread.currentThread().getName() + \" incremented to: \" + cas.get());\n}\n}\n}, \"Worker-\" + threadId);\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final value: \" + cas.get());\nSystem.out.println(\"Expected value: \" + (threadCount * iterationsPerThread));\n}\n}",
        "max_depth": "101",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.76%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.49%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=264717,visited=31561,backtracked=295273,end=2015\nsearch:             maxDepth=1010,constraints=115072\nchoice generators:  thread=149659 (signal=0,lock=57973,sharedRef=158,threadApi=28964,reschedule=2038), data=0\nheap:               new=539276,released=494615,maxLive=719,gcCycles=250056\ninstructions:       25678972\nmax memory:         1017MB\nloaded code:        classes=136,methods=2410\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.77%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.49%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=258052,visited=41117,backtracked=298163,end=2012\nsearch:             maxDepth=1010,constraints=106964\nchoice generators:  thread=151110 (signal=0,lock=69262,sharedRef=189,threadApi=23157,reschedule=2045), data=0\nheap:               new=515773,released=433462,maxLive=726,gcCycles=264712\ninstructions:       27512126\nmax memory:         1018MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.76%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=260216,visited=31547,backtracked=290753,end=2012\nsearch:             maxDepth=1010,constraints=112831\nchoice generators:  thread=147402 (signal=0,lock=57221,sharedRef=144,threadApi=28596,reschedule=2033), data=0\nheap:               new=534018,released=489122,maxLive=719,gcCycles=246291\ninstructions:       25432728\nmax memory:         1017MB\nloaded code:        classes=136,methods=2410\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            59.6,
            60.44,
            59.6
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ArcaneGauge {\n    private int mana;\n    \n    public ArcaneGauge(int initialMana) {\n        this.mana = initialMana;\n    }\n    \n    public synchronized int get() {\n        return mana;\n    }\n    \n    public synchronized int compareAndSwap(int expectedMana, int newMana) {\n        int oldMana = mana;\n        if (mana == expectedMana) {\n            mana = newMana;\n        }\n        return oldMana;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedMana, int newMana) {\n        return compareAndSwap(expectedMana, newMana) == expectedMana;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        ArcaneGauge gauge = new ArcaneGauge(100);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int current = gauge.get();\n                boolean success = gauge.compareAndSet(current, current + 10);\n                System.out.println(\"Thread 1: Attempted to increase mana from \" + current + \n                                 \" to \" + (current + 10) + \", success: \" + success);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 5; i++) {\n            int current = gauge.get();\n            boolean success = gauge.compareAndSet(current, current - 5);\n            System.out.println(\"Main Thread: Attempted to decrease mana from \" + current + \n                             \" to \" + (current - 5) + \", success: \" + success);\n            Thread.sleep(60);\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        System.out.println(\"Final mana level: \" + gauge.get());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ArcaneGauge {\n    private int mana;\n    \n    public ArcaneGauge(int initialMana) {\n        this.mana = initialMana;\n    }\n    \n    public synchronized int get() {\n        return mana;\n    }\n    \n    public synchronized int compareAndSwap(int expectedMana, int newMana) {\n        int oldMana = mana;\n        if (mana == expectedMana) {\n            mana = newMana;\n        }\n        return oldMana;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedMana, int newMana) {\n        int oldMana = compareAndSwap(expectedMana, newMana);\n        return oldMana == expectedMana;\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        ArcaneGauge gauge = new ArcaneGauge(100);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int current = gauge.get();\n                boolean success = gauge.compareAndSet(current, current + 10);\n                System.out.println(\"Thread 1 - Attempt \" + (i + 1) + \": \" + \n                    (success ? \"Success\" : \"Failed\") + \", New mana: \" + gauge.get());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 5; i++) {\n            int current = gauge.get();\n            boolean success = gauge.compareAndSet(current, current - 5);\n            System.out.println(\"Main Thread - Attempt \" + (i + 1) + \": \" + \n                (success ? \"Success\" : \"Failed\") + \", New mana: \" + gauge.get());\n            try {\n                Thread.sleep(150);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        System.out.println(\"Final mana level: \" + gauge.get());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ArcaneGauge {\n    private int mana;\n    \n    public ArcaneGauge(int initialMana) {\n        this.mana = initialMana;\n    }\n    \n    public synchronized int get() {\n        return mana;\n    }\n    \n    public synchronized int compareAndSwap(int expectedMana, int newMana) {\n        int oldMana = mana;\n        if (mana == expectedMana) {\n            mana = newMana;\n        }\n        return oldMana;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedMana, int newMana) {\n        return compareAndSwap(expectedMana, newMana) == expectedMana;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        ArcaneGauge gauge = new ArcaneGauge(100);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                int current = gauge.get();\n                boolean success = gauge.compareAndSet(current, current + 10);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 10) + \", success: \" + success);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        for (int i = 0; i < 5; i++) {\n            int current = gauge.get();\n            boolean success = gauge.compareAndSet(current, current - 5);\n            System.out.println(\"Main thread: Attempted to change \" + current + \" to \" + (current - 5) + \", success: \" + success);\n            Thread.sleep(60);\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        System.out.println(\"Final mana level: \" + gauge.get());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Simulated CAS operation. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class called EtherealCounter that simulates the behavior of a Compare-and-Swap (CAS) incantation, often used in concurrent magic for atomic transformations. The class should maintain an internal integer aura and provide thread-safe rituals to interact with it. \n\nThe class should include: \n\nA private integer field aura to store the current mystical value. \nA synchronized get() method that reveals the current aura. \nA synchronized compareAndSwap(int expectedAura, int newAura) method that checks if the current aura matches the expectedAura. If it does, it shifts the aura to newAura; otherwise, it leaves the aura unchanged. This method should return the original (old) aura before any potential shift. \nA synchronized compareAndSet(int expectedAura, int newAura) method that uses compareAndSwap() to determine whether the aura was successfully shifted. It should return true if the aura was changed (i.e., if the old aura matched the expected aura), and false otherwise. \n\nEnsure that all methods are thread-safe using the synchronized keyword to prevent concurrent energy clashes when accessed by multiple threads. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EtherealCounter {\n    private int aura;\n    \n    public EtherealCounter() {\n        this.aura = 0;\n    }\n    \n    public synchronized int get() {\n        return aura;\n    }\n    \n    public synchronized int compareAndSwap(int expectedAura, int newAura) {\n        int oldAura = aura;\n        if (aura == expectedAura) {\n            aura = newAura;\n        }\n        return oldAura;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedAura, int newAura) {\n        int oldAura = compareAndSwap(expectedAura, newAura);\n        return oldAura == expectedAura;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        EtherealCounter counter = new EtherealCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: CAS \" + current + \" -> \" + (current + 1) + \" = \" + success);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                int oldValue = counter.compareAndSwap(current, current + 10);\n                System.out.println(\"Thread 2: Swap \" + current + \" -> \" + (current + 10) + \", old = \" + oldValue);\n                try {\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        task2.run();\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final aura: \" + counter.get());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EtherealCounter {\n    private int aura;\n    \n    public EtherealCounter() {\n        this.aura = 0;\n    }\n    \n    public EtherealCounter(int initialAura) {\n        this.aura = initialAura;\n    }\n    \n    public synchronized int get() {\n        return aura;\n    }\n    \n    public synchronized int compareAndSwap(int expectedAura, int newAura) {\n        int oldAura = aura;\n        if (aura == expectedAura) {\n            aura = newAura;\n        }\n        return oldAura;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedAura, int newAura) {\n        int oldAura = compareAndSwap(expectedAura, newAura);\n        return oldAura == expectedAura;\n    }\n    \n    public static void main(String[] args) {\n        EtherealCounter counter = new EtherealCounter(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: CAS(\" + current + \", \" + (current + 1) + \") = \" + success);\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                int oldValue = counter.compareAndSwap(current, current + 10);\n                System.out.println(\"Thread 2: Swap(\" + current + \", \" + (current + 10) + \") returned \" + oldValue);\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        \n        for (int i = 0; i < 5; i++) {\n            int current = counter.get();\n            boolean result = counter.compareAndSet(current, current + 100);\n            System.out.println(\"Main Thread: CAS(\" + current + \", \" + (current + 100) + \") = \" + result);\n            try {\n                Thread.sleep(20);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final aura value: \" + counter.get());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EtherealCounter {\n    private int aura;\n    \n    public EtherealCounter() {\n        this.aura = 0;\n    }\n    \n    public synchronized int get() {\n        return aura;\n    }\n    \n    public synchronized int compareAndSwap(int expectedAura, int newAura) {\n        int oldAura = aura;\n        if (aura == expectedAura) {\n            aura = newAura;\n        }\n        return oldAura;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedAura, int newAura) {\n        return compareAndSwap(expectedAura, newAura) == expectedAura;\n    }\n    \n    public static void main(String[] args) {\n        EtherealCounter counter = new EtherealCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 1) + \", success: \" + success);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 2);\n                System.out.println(\"Thread 2: Attempted to change \" + current + \" to \" + (current + 2) + \", success: \" + success);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        \n        task2.run();\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final aura value: \" + counter.get());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class SimulatedCAS {\nprivate int value;\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized int compareAndSwap(int expectedValue, int newValue) {\nint oldValue = value;\nif (oldValue == expectedValue) {\nvalue = newValue;\n}\nreturn oldValue;\n}\n\npublic synchronized boolean compareAndSet(int expectedValue, int newValue) {\nreturn expectedValue == compareAndSwap(expectedValue, newValue);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal SimulatedCAS cas = new SimulatedCAS();\n\n// Reduce number of threads and iterations for faster JPF analysis\nint threadCount = 2;\nint iterationsPerThread = 3;\n\nThread[] threads = new Thread[threadCount];\nfor (int i = 0; i < threadCount; i++) {\nfinal int threadId = i;\nthreads[i] = new Thread(new Runnable() {\npublic void run() {\nfor (int j = 0; j < iterationsPerThread; j++) {\nint expected;\ndo {\nexpected = cas.get();\n} while (!cas.compareAndSet(expected, expected + 1));\nSystem.out.println(Thread.currentThread().getName() + \" incremented to: \" + cas.get());\n}\n}\n}, \"Worker-\" + threadId);\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final value: \" + cas.get());\nSystem.out.println(\"Expected value: \" + (threadCount * iterationsPerThread));\n}\n}",
        "max_depth": "101",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.74%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.50%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=270866,visited=31535,backtracked=301392,end=2006\nsearch:             maxDepth=1010,constraints=118165\nchoice generators:  thread=152716 (signal=0,lock=59008,sharedRef=141,threadApi=29469,reschedule=2027), data=0\nheap:               new=472493,released=422490,maxLive=725,gcCycles=255159\ninstructions:       26103400\nmax memory:         1017MB\nloaded code:        classes=136,methods=2412\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.93%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.90%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=204805,visited=81551,backtracked=285518,end=5108\nsearch:             maxDepth=1010,constraints=58704\nchoice generators:  thread=146155 (signal=0,lock=70280,sharedRef=271,threadApi=35118,reschedule=5137), data=0\nheap:               new=786100,released=675184,maxLive=723,gcCycles=246490\ninstructions:       40212312\nmax memory:         1015MB\nloaded code:        classes=136,methods=2413\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.77%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.47%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=257140,visited=31543,backtracked=287674,end=2009\nsearch:             maxDepth=1010,constraints=111292\nchoice generators:  thread=145861 (signal=0,lock=56716,sharedRef=141,threadApi=28334,reschedule=2029), data=0\nheap:               new=530338,released=487308,maxLive=723,gcCycles=243723\ninstructions:       25295010\nmax memory:         1016MB\nloaded code:        classes=136,methods=2412\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            59.67,
            63.35,
            56.44
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EtherealCounter {\n    private int aura;\n    \n    public EtherealCounter() {\n        this.aura = 0;\n    }\n    \n    public synchronized int get() {\n        return aura;\n    }\n    \n    public synchronized int compareAndSwap(int expectedAura, int newAura) {\n        int oldAura = aura;\n        if (aura == expectedAura) {\n            aura = newAura;\n        }\n        return oldAura;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedAura, int newAura) {\n        int oldAura = compareAndSwap(expectedAura, newAura);\n        return oldAura == expectedAura;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        EtherealCounter counter = new EtherealCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: CAS \" + current + \" -> \" + (current + 1) + \" = \" + success);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                int oldValue = counter.compareAndSwap(current, current + 10);\n                System.out.println(\"Thread 2: Swap \" + current + \" -> \" + (current + 10) + \", old = \" + oldValue);\n                try {\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        task2.run();\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final aura: \" + counter.get());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EtherealCounter {\n    private int aura;\n    \n    public EtherealCounter() {\n        this.aura = 0;\n    }\n    \n    public EtherealCounter(int initialAura) {\n        this.aura = initialAura;\n    }\n    \n    public synchronized int get() {\n        return aura;\n    }\n    \n    public synchronized int compareAndSwap(int expectedAura, int newAura) {\n        int oldAura = aura;\n        if (aura == expectedAura) {\n            aura = newAura;\n        }\n        return oldAura;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedAura, int newAura) {\n        int oldAura = compareAndSwap(expectedAura, newAura);\n        return oldAura == expectedAura;\n    }\n    \n    public static void main(String[] args) {\n        EtherealCounter counter = new EtherealCounter(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: CAS(\" + current + \", \" + (current + 1) + \") = \" + success);\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                int oldValue = counter.compareAndSwap(current, current + 10);\n                System.out.println(\"Thread 2: Swap(\" + current + \", \" + (current + 10) + \") returned \" + oldValue);\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        \n        for (int i = 0; i < 5; i++) {\n            int current = counter.get();\n            boolean result = counter.compareAndSet(current, current + 100);\n            System.out.println(\"Main Thread: CAS(\" + current + \", \" + (current + 100) + \") = \" + result);\n            try {\n                Thread.sleep(20);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final aura value: \" + counter.get());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EtherealCounter {\n    private int aura;\n    \n    public EtherealCounter() {\n        this.aura = 0;\n    }\n    \n    public synchronized int get() {\n        return aura;\n    }\n    \n    public synchronized int compareAndSwap(int expectedAura, int newAura) {\n        int oldAura = aura;\n        if (aura == expectedAura) {\n            aura = newAura;\n        }\n        return oldAura;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedAura, int newAura) {\n        return compareAndSwap(expectedAura, newAura) == expectedAura;\n    }\n    \n    public static void main(String[] args) {\n        EtherealCounter counter = new EtherealCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: Attempted to change \" + current + \" to \" + (current + 1) + \", success: \" + success);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = counter.get();\n                boolean success = counter.compareAndSet(current, current + 2);\n                System.out.println(\"Thread 2: Attempted to change \" + current + \" to \" + (current + 2) + \", success: \" + success);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        \n        task2.run();\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final aura value: \" + counter.get());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Eager initialization. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that demonstrates eager summoning of a singleton relic. The program should include a class with a static instance of the relic that is conjured at class loading. Provide a static method to retrieve this relic. The relic class should have a simple method (e.g., invokeSpell) that outputs an incantation to the console. In the main method, create and start multiple threads that access the shared relic and invoke the invokeSpell method. Ensure all threads complete before printing a final message of ritual completion. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class RelicSummoner {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Relic relic = Relic.getInstance();\n                System.out.println(\"Thread \" + threadId + \" accessing relic\");\n                relic.invokeSpell();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Ritual completion\");\n    }\n}\n\nclass Relic {\n    private static final Relic INSTANCE = new Relic();\n    \n    private Relic() {\n        System.out.println(\"Relic conjured at class loading\");\n    }\n    \n    public static Relic getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void invokeSpell() {\n        System.out.println(\"Casting ancient incantation from thread: \" + Thread.currentThread().getName());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class RelicSummoner {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Relic relic = Relic.getRelic();\n                System.out.println(\"Thread \" + threadId + \" accessing relic\");\n                relic.invokeSpell();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Ritual completion\");\n    }\n}\n\nclass Relic {\n    private static final Relic INSTANCE = new Relic();\n    \n    private Relic() {\n        System.out.println(\"Relic conjured\");\n    }\n    \n    public static Relic getRelic() {\n        return INSTANCE;\n    }\n    \n    public synchronized void invokeSpell() {\n        System.out.println(\"Abracadabra! Spell invoked by \" + Thread.currentThread().getName());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class RelicSummoner {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Relic relic = Relic.getInstance();\n                System.out.println(\"Thread \" + threadId + \" accessing relic\");\n                relic.invokeSpell();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Ritual completion\");\n    }\n}\n\nclass Relic {\n    private static final Relic INSTANCE = new Relic();\n    \n    private Relic() {\n        System.out.println(\"Relic conjured at class loading\");\n    }\n    \n    public static Relic getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void invokeSpell() {\n        System.out.println(\"Casting ancient incantation by thread: \" + Thread.currentThread().getName());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class EagerInitialization {\nprivate static final Resource resource = new Resource();\n\npublic static Resource getResource() {\nreturn resource;\n}\n\nstatic class Resource {\npublic void doSomething() {\nSystem.out.println(Thread.currentThread().getName() + \": Resource is doing something.\");\n}\n}\n\npublic static void main(String[] args) {\nRunnable task = () -> {\nResource res = getResource();\nres.doSomething();\n};\n\nThread t1 = new Thread(task, \"Thread-1\");\nThread t2 = new Thread(task, \"Thread-2\");\nThread t3 = new Thread(task, \"Thread-3\");\n\nt1.start();\nt2.start();\nt3.start();\n\ntry {\nt1.join();\nt2.join();\nt3.join();\n} catch (InterruptedException e) {\ne.printStackTrace();\n}\n\nSystem.out.println(\"All threads completed.\");\n}\n}",
        "max_depth": "46",
        "jpf_details": [
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.62%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.64%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.65%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=176193,visited=102486,backtracked=278219,end=1\nsearch:             maxDepth=460,constraints=140311\nchoice generators:  thread=70287 (signal=0,lock=2674,sharedRef=52154,threadApi=3,reschedule=507), data=0\nheap:               new=150672,released=191537,maxLive=736,gcCycles=277739\ninstructions:       17020646\nmax memory:         1020MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.34%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.36%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.39%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=133517,visited=151989,backtracked=285050,end=1\nsearch:             maxDepth=460,constraints=87619\nchoice generators:  thread=72153 (signal=0,lock=5128,sharedRef=58341,threadApi=3,reschedule=1231), data=0\nheap:               new=311405,released=422312,maxLive=736,gcCycles=282157\ninstructions:       24233927\nmax memory:         1019MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.62%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.64%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.64%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=176437,visited=104134,backtracked=280120,end=1\nsearch:             maxDepth=460,constraints=140187\nchoice generators:  thread=70761 (signal=0,lock=2772,sharedRef=52590,threadApi=3,reschedule=525), data=0\nheap:               new=156971,released=198846,maxLive=736,gcCycles=279434\ninstructions:       17258481\nmax memory:         1020MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            52.29,
            52.29,
            52.29
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class RelicSummoner {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Relic relic = Relic.getInstance();\n                System.out.println(\"Thread \" + threadId + \" accessing relic\");\n                relic.invokeSpell();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Ritual completion\");\n    }\n}\n\nclass Relic {\n    private static final Relic INSTANCE = new Relic();\n    \n    private Relic() {\n        System.out.println(\"Relic conjured at class loading\");\n    }\n    \n    public static Relic getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void invokeSpell() {\n        System.out.println(\"Casting ancient incantation from thread: \" + Thread.currentThread().getName());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class RelicSummoner {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Relic relic = Relic.getRelic();\n                System.out.println(\"Thread \" + threadId + \" accessing relic\");\n                relic.invokeSpell();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Ritual completion\");\n    }\n}\n\nclass Relic {\n    private static final Relic INSTANCE = new Relic();\n    \n    private Relic() {\n        System.out.println(\"Relic conjured\");\n    }\n    \n    public static Relic getRelic() {\n        return INSTANCE;\n    }\n    \n    public synchronized void invokeSpell() {\n        System.out.println(\"Abracadabra! Spell invoked by \" + Thread.currentThread().getName());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class RelicSummoner {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Relic relic = Relic.getInstance();\n                System.out.println(\"Thread \" + threadId + \" accessing relic\");\n                relic.invokeSpell();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Ritual completion\");\n    }\n}\n\nclass Relic {\n    private static final Relic INSTANCE = new Relic();\n    \n    private Relic() {\n        System.out.println(\"Relic conjured at class loading\");\n    }\n    \n    public static Relic getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void invokeSpell() {\n        System.out.println(\"Casting ancient incantation by thread: \" + Thread.currentThread().getName());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Eager initialization. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that demonstrates eager manifestation of a singleton artifact. The program should include a class with a static instance of the artifact that is materialized at class loading. Provide a static method to access this artifact. The artifact class should have a simple method (e.g., performRitual) that prints a magical message to the console. In the main method, create and start multiple threads that interact with the shared artifact and invoke the performRitual method. Ensure all threads finish before printing a final message signaling the ritual’s completion. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MagicalRitual {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                System.out.println(\"Thread \" + threadId + \" accessing the artifact...\");\n                MagicalArtifact.getInstance().performRitual();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"The ritual is complete!\");\n    }\n}\n\nclass MagicalArtifact {\n    private static final MagicalArtifact INSTANCE = new MagicalArtifact();\n    \n    private MagicalArtifact() {\n        System.out.println(\"The magical artifact has been manifested!\");\n    }\n    \n    public static MagicalArtifact getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void performRitual() {\n        System.out.println(\"✨ Casting ancient spell from thread: \" + Thread.currentThread().getName() + \" ✨\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        System.out.println(\"Spell cast successfully by: \" + Thread.currentThread().getName());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MagicalRitual {\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        executor.submit(() -> {\n            MagicalArtifact.getInstance().performRitual();\n        });\n        \n        executor.submit(() -> {\n            MagicalArtifact.getInstance().performRitual();\n        });\n        \n        executor.submit(() -> {\n            MagicalArtifact.getInstance().performRitual();\n        });\n        \n        executor.shutdown();\n        \n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"The ritual is complete!\");\n    }\n}\n\nclass MagicalArtifact {\n    private static final MagicalArtifact INSTANCE = new MagicalArtifact();\n    \n    private MagicalArtifact() {\n        System.out.println(\"The magical artifact has been created!\");\n    }\n    \n    public static MagicalArtifact getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void performRitual() {\n        System.out.println(\"Thread \" + Thread.currentThread().getName() + \" invokes the ancient magic!\");\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MagicalRitual {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                System.out.println(\"Thread \" + threadId + \" accessing the artifact...\");\n                MagicalArtifact.getInstance().performRitual();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"The ritual has been completed!\");\n    }\n}\n\nclass MagicalArtifact {\n    private static final MagicalArtifact INSTANCE = new MagicalArtifact();\n    \n    private MagicalArtifact() {\n        System.out.println(\"The ancient artifact materializes with ethereal energy...\");\n    }\n    \n    public static MagicalArtifact getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void performRitual() {\n        System.out.println(\"✨ The artifact channels mystical powers through Thread: \" + Thread.currentThread().getName() + \" ✨\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class EagerInitialization {\nprivate static final Resource resource = new Resource();\n\npublic static Resource getResource() {\nreturn resource;\n}\n\nstatic class Resource {\npublic void doSomething() {\nSystem.out.println(Thread.currentThread().getName() + \": Resource is doing something.\");\n}\n}\n\npublic static void main(String[] args) {\nRunnable task = () -> {\nResource res = getResource();\nres.doSomething();\n};\n\nThread t1 = new Thread(task, \"Thread-1\");\nThread t2 = new Thread(task, \"Thread-2\");\nThread t3 = new Thread(task, \"Thread-3\");\n\nt1.start();\nt2.start();\nt3.start();\n\ntry {\nt1.join();\nt2.join();\nt3.join();\n} catch (InterruptedException e) {\ne.printStackTrace();\n}\n\nSystem.out.println(\"All threads completed.\");\n}\n}",
        "max_depth": "46",
        "jpf_details": [
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.57%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.59%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.58%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=173364,visited=99519,backtracked=272423,end=1\nsearch:             maxDepth=460,constraints=138038\nchoice generators:  thread=68822 (signal=0,lock=2589,sharedRef=49897,threadApi=1143,reschedule=427), data=0\nheap:               new=173234,released=200754,maxLive=740,gcCycles=271990\ninstructions:       16620163\nmax memory:         1019MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.62%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.62%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.62%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=175466,visited=103551,backtracked=278564,end=1\nsearch:             maxDepth=460,constraints=139586\nchoice generators:  thread=70351 (signal=0,lock=3480,sharedRef=51524,threadApi=3,reschedule=639), data=0\nheap:               new=144001,released=184021,maxLive=740,gcCycles=277322\ninstructions:       17270046\nmax memory:         1020MB\nloaded code:        classes=137,methods=2415\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.52%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.55%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.55%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=174060,visited=102433,backtracked=276036,end=1\nsearch:             maxDepth=460,constraints=138157\nchoice generators:  thread=69769 (signal=0,lock=2724,sharedRef=50681,threadApi=1215,reschedule=466), data=0\nheap:               new=162651,released=196134,maxLive=738,gcCycles=275172\ninstructions:       16931245\nmax memory:         1020MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            54.36,
            63.73,
            54.36
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MagicalRitual {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                System.out.println(\"Thread \" + threadId + \" accessing the artifact...\");\n                MagicalArtifact.getInstance().performRitual();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"The ritual is complete!\");\n    }\n}\n\nclass MagicalArtifact {\n    private static final MagicalArtifact INSTANCE = new MagicalArtifact();\n    \n    private MagicalArtifact() {\n        System.out.println(\"The magical artifact has been manifested!\");\n    }\n    \n    public static MagicalArtifact getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void performRitual() {\n        System.out.println(\"✨ Casting ancient spell from thread: \" + Thread.currentThread().getName() + \" ✨\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        System.out.println(\"Spell cast successfully by: \" + Thread.currentThread().getName());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MagicalRitual {\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        executor.submit(() -> {\n            MagicalArtifact.getInstance().performRitual();\n        });\n        \n        executor.submit(() -> {\n            MagicalArtifact.getInstance().performRitual();\n        });\n        \n        executor.submit(() -> {\n            MagicalArtifact.getInstance().performRitual();\n        });\n        \n        executor.shutdown();\n        \n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"The ritual is complete!\");\n    }\n}\n\nclass MagicalArtifact {\n    private static final MagicalArtifact INSTANCE = new MagicalArtifact();\n    \n    private MagicalArtifact() {\n        System.out.println(\"The magical artifact has been created!\");\n    }\n    \n    public static MagicalArtifact getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void performRitual() {\n        System.out.println(\"Thread \" + Thread.currentThread().getName() + \" invokes the ancient magic!\");\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MagicalRitual {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                System.out.println(\"Thread \" + threadId + \" accessing the artifact...\");\n                MagicalArtifact.getInstance().performRitual();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"The ritual has been completed!\");\n    }\n}\n\nclass MagicalArtifact {\n    private static final MagicalArtifact INSTANCE = new MagicalArtifact();\n    \n    private MagicalArtifact() {\n        System.out.println(\"The ancient artifact materializes with ethereal energy...\");\n    }\n    \n    public static MagicalArtifact getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void performRitual() {\n        System.out.println(\"✨ The artifact channels mystical powers through Thread: \" + Thread.currentThread().getName() + \" ✨\");\n        try {\n            Thread.sleep(500);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Eager initialization. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that demonstrates eager conjuration of a singleton talisman. The program should include a class with a static instance of the talisman that is summoned at class loading. Provide a static method to obtain this talisman. The talisman class should have a simple method (e.g., activate) that displays a mystical message to the console. In the main method, create and start multiple threads that access the shared talisman and invoke the activate method. Ensure all threads complete before printing a final message marking the completion of the ritual. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticalRitual {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Talisman talisman = Talisman.getInstance();\n                System.out.println(\"Thread \" + threadId + \" accessing the talisman...\");\n                talisman.activate();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"The ritual is complete. The talisman has been shared among all seekers.\");\n    }\n}\n\nclass Talisman {\n    private static final Talisman INSTANCE = new Talisman();\n    \n    private Talisman() {\n        System.out.println(\"The ancient talisman has been summoned into existence!\");\n    }\n    \n    public static Talisman getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void activate() {\n        System.out.println(\"✨ The talisman glows with mystical energy in thread: \" + Thread.currentThread().getName());\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticalRitual {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadNum = i + 1;\n            executor.submit(() -> {\n                Talisman talisman = Talisman.getInstance();\n                System.out.println(\"Thread \" + threadNum + \" accessing the talisman...\");\n                talisman.activate();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"The ritual is complete. The mystical energies have been harmonized.\");\n    }\n}\n\nclass Talisman {\n    private static final Talisman INSTANCE = new Talisman();\n    \n    private Talisman() {\n        System.out.println(\"The ancient talisman has been summoned into existence!\");\n    }\n    \n    public static Talisman getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void activate() {\n        System.out.println(\"✨ The talisman glows with ethereal power! Thread: \" + Thread.currentThread().getName());\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticalRitual {\n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Talisman talisman = Talisman.getInstance();\n                System.out.println(\"Thread \" + threadId + \" accessing the talisman...\");\n                talisman.activate();\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"The ritual is complete. All threads have accessed the sacred talisman.\");\n    }\n}\n\nclass Talisman {\n    private static final Talisman INSTANCE = new Talisman();\n    \n    private Talisman() {\n        System.out.println(\"The ancient talisman has been conjured!\");\n    }\n    \n    public static Talisman getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void activate() {\n        System.out.println(\"✨ The talisman glows with mystical energy from thread: \" + Thread.currentThread().getName() + \" ✨\");\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class EagerInitialization {\nprivate static final Resource resource = new Resource();\n\npublic static Resource getResource() {\nreturn resource;\n}\n\nstatic class Resource {\npublic void doSomething() {\nSystem.out.println(Thread.currentThread().getName() + \": Resource is doing something.\");\n}\n}\n\npublic static void main(String[] args) {\nRunnable task = () -> {\nResource res = getResource();\nres.doSomething();\n};\n\nThread t1 = new Thread(task, \"Thread-1\");\nThread t2 = new Thread(task, \"Thread-2\");\nThread t3 = new Thread(task, \"Thread-3\");\n\nt1.start();\nt2.start();\nt3.start();\n\ntry {\nt1.join();\nt2.join();\nt3.join();\n} catch (InterruptedException e) {\ne.printStackTrace();\n}\n\nSystem.out.println(\"All threads completed.\");\n}\n}",
        "max_depth": "46",
        "jpf_details": [
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.55%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.56%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.56%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=171340,visited=99590,backtracked=270470,end=1\nsearch:             maxDepth=460,constraints=136227\nchoice generators:  thread=68370 (signal=0,lock=2611,sharedRef=49624,threadApi=1158,reschedule=433), data=0\nheap:               new=144042,released=182894,maxLive=736,gcCycles=269850\ninstructions:       16459979\nmax memory:         1019MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.54%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.56%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.56%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=175124,visited=101570,backtracked=276236,end=1\nsearch:             maxDepth=460,constraints=139321\nchoice generators:  thread=69816 (signal=0,lock=2659,sharedRef=50671,threadApi=1181,reschedule=443), data=0\nheap:               new=148638,released=187942,maxLive=736,gcCycles=275506\ninstructions:       16813516\nmax memory:         1019MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.56%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.58%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.58%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=169581,visited=98420,backtracked=267541,end=1\nsearch:             maxDepth=460,constraints=134729\nchoice generators:  thread=67601 (signal=0,lock=2577,sharedRef=49071,threadApi=1140,reschedule=421), data=0\nheap:               new=148296,released=181068,maxLive=738,gcCycles=266946\ninstructions:       16346762\nmax memory:         1018MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            53.32,
            53.32,
            53.32
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticalRitual {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Talisman talisman = Talisman.getInstance();\n                System.out.println(\"Thread \" + threadId + \" accessing the talisman...\");\n                talisman.activate();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"The ritual is complete. The talisman has been shared among all seekers.\");\n    }\n}\n\nclass Talisman {\n    private static final Talisman INSTANCE = new Talisman();\n    \n    private Talisman() {\n        System.out.println(\"The ancient talisman has been summoned into existence!\");\n    }\n    \n    public static Talisman getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void activate() {\n        System.out.println(\"✨ The talisman glows with mystical energy in thread: \" + Thread.currentThread().getName());\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticalRitual {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadNum = i + 1;\n            executor.submit(() -> {\n                Talisman talisman = Talisman.getInstance();\n                System.out.println(\"Thread \" + threadNum + \" accessing the talisman...\");\n                talisman.activate();\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"The ritual is complete. The mystical energies have been harmonized.\");\n    }\n}\n\nclass Talisman {\n    private static final Talisman INSTANCE = new Talisman();\n    \n    private Talisman() {\n        System.out.println(\"The ancient talisman has been summoned into existence!\");\n    }\n    \n    public static Talisman getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void activate() {\n        System.out.println(\"✨ The talisman glows with ethereal power! Thread: \" + Thread.currentThread().getName());\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticalRitual {\n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Talisman talisman = Talisman.getInstance();\n                System.out.println(\"Thread \" + threadId + \" accessing the talisman...\");\n                talisman.activate();\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"The ritual is complete. All threads have accessed the sacred talisman.\");\n    }\n}\n\nclass Talisman {\n    private static final Talisman INSTANCE = new Talisman();\n    \n    private Talisman() {\n        System.out.println(\"The ancient talisman has been conjured!\");\n    }\n    \n    public static Talisman getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void activate() {\n        System.out.println(\"✨ The talisman glows with mystical energy from thread: \" + Thread.currentThread().getName() + \" ✨\");\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Monitor-based vehicle tracker implementation. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe ChronomanticDragonTracker class in Java that enchants the whereabouts of dragons using a synchronized constellation. The class should take an initial Constellation<String, MutableOrb> in its constructor and make a deep copy of it to prevent external tampering. All public methods must be synchronized to ensure thread safety. Implement a getConstellations() method that returns an unmodifiable deep copy of the entire constellation. Also provide a getOrb(String sigil) method that returns a new MutableOrb copy of the location for the given sigil, or null if not found. Include a setOrb(String sigil, int shimmerX, int shimmerY) method that updates the coordinates for the specified dragon and throws an IllegalArgumentException if the sigil is not present. Use a private static deepClone method to create a new constellation with copies of all MutableOrb values. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableOrb {\n    private int shimmerX;\n    private int shimmerY;\n    \n    public MutableOrb(int shimmerX, int shimmerY) {\n        this.shimmerX = shimmerX;\n        this.shimmerY = shimmerY;\n    }\n    \n    public MutableOrb(MutableOrb other) {\n        this.shimmerX = other.shimmerX;\n        this.shimmerY = other.shimmerY;\n    }\n    \n    public int getShimmerX() {\n        return shimmerX;\n    }\n    \n    public int getShimmerY() {\n        return shimmerY;\n    }\n    \n    public void setShimmerX(int shimmerX) {\n        this.shimmerX = shimmerX;\n    }\n    \n    public void setShimmerY(int shimmerY) {\n        this.shimmerY = shimmerY;\n    }\n}\n\nclass Constellation<K, V> extends HashMap<K, V> {\n    public Constellation() {\n        super();\n    }\n    \n    public Constellation(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass ChronomanticDragonTracker {\n    private final Constellation<String, MutableOrb> constellation;\n    \n    public ChronomanticDragonTracker(Constellation<String, MutableOrb> initialConstellation) {\n        this.constellation = deepClone(initialConstellation);\n    }\n    \n    public synchronized Map<String, MutableOrb> getConstellations() {\n        return Collections.unmodifiableMap(deepClone(constellation));\n    }\n    \n    public synchronized MutableOrb getOrb(String sigil) {\n        MutableOrb orb = constellation.get(sigil);\n        return orb != null ? new MutableOrb(orb) : null;\n    }\n    \n    public synchronized void setOrb(String sigil, int shimmerX, int shimmerY) {\n        MutableOrb orb = constellation.get(sigil);\n        if (orb == null) {\n            throw new IllegalArgumentException(\"Sigil not present: \" + sigil);\n        }\n        orb.setShimmerX(shimmerX);\n        orb.setShimmerY(shimmerY);\n    }\n    \n    private static Constellation<String, MutableOrb> deepClone(Constellation<String, MutableOrb> original) {\n        Constellation<String, MutableOrb> clone = new Constellation<>();\n        for (Map.Entry<String, MutableOrb> entry : original.entrySet()) {\n            clone.put(entry.getKey(), new MutableOrb(entry.getValue()));\n        }\n        return clone;\n    }\n}\n\npublic class DragonTrackerApp {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Constellation<String, MutableOrb> initialConstellation = new Constellation<>();\n        initialConstellation.put(\"FireDragon\", new MutableOrb(100, 200));\n        initialConstellation.put(\"IceDragon\", new MutableOrb(300, 400));\n        initialConstellation.put(\"WindDragon\", new MutableOrb(500, 600));\n        \n        ChronomanticDragonTracker tracker = new ChronomanticDragonTracker(initialConstellation);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setOrb(\"FireDragon\", 100 + i * 10, 200 + i * 10);\n                MutableOrb orb = tracker.getOrb(\"FireDragon\");\n                System.out.println(\"Thread 1 - FireDragon: \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setOrb(\"IceDragon\", 300 - i * 5, 400 - i * 5);\n                MutableOrb orb = tracker.getOrb(\"IceDragon\");\n                System.out.println(\"Thread 2 - IceDragon: \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Final constellations:\");\n        Map<String, MutableOrb> finalConstellations = tracker.getConstellations();\n        for (Map.Entry<String, MutableOrb> entry : finalConstellations.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + \n                entry.getValue().getShimmerX() + \", \" + entry.getValue().getShimmerY());\n        }\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableOrb {\n    private int shimmerX;\n    private int shimmerY;\n    \n    public MutableOrb(int shimmerX, int shimmerY) {\n        this.shimmerX = shimmerX;\n        this.shimmerY = shimmerY;\n    }\n    \n    public MutableOrb(MutableOrb other) {\n        this.shimmerX = other.shimmerX;\n        this.shimmerY = other.shimmerY;\n    }\n    \n    public int getShimmerX() {\n        return shimmerX;\n    }\n    \n    public int getShimmerY() {\n        return shimmerY;\n    }\n    \n    public void setShimmerX(int shimmerX) {\n        this.shimmerX = shimmerX;\n    }\n    \n    public void setShimmerY(int shimmerY) {\n        this.shimmerY = shimmerY;\n    }\n}\n\nclass Constellation<K, V> extends HashMap<K, V> {\n    public Constellation() {\n        super();\n    }\n    \n    public Constellation(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass ChronomanticDragonTracker {\n    private final Constellation<String, MutableOrb> constellation;\n    \n    public ChronomanticDragonTracker(Constellation<String, MutableOrb> initialConstellation) {\n        this.constellation = deepClone(initialConstellation);\n    }\n    \n    public synchronized Map<String, MutableOrb> getConstellations() {\n        return Collections.unmodifiableMap(deepClone(constellation));\n    }\n    \n    public synchronized MutableOrb getOrb(String sigil) {\n        MutableOrb orb = constellation.get(sigil);\n        return orb == null ? null : new MutableOrb(orb);\n    }\n    \n    public synchronized void setOrb(String sigil, int shimmerX, int shimmerY) {\n        MutableOrb orb = constellation.get(sigil);\n        if (orb == null) {\n            throw new IllegalArgumentException(\"Sigil not found: \" + sigil);\n        }\n        orb.setShimmerX(shimmerX);\n        orb.setShimmerY(shimmerY);\n    }\n    \n    private static Constellation<String, MutableOrb> deepClone(Constellation<String, MutableOrb> original) {\n        Constellation<String, MutableOrb> clone = new Constellation<>();\n        for (Map.Entry<String, MutableOrb> entry : original.entrySet()) {\n            clone.put(entry.getKey(), new MutableOrb(entry.getValue()));\n        }\n        return clone;\n    }\n}\n\npublic class DragonTrackerApp {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Constellation<String, MutableOrb> initialConstellation = new Constellation<>();\n        initialConstellation.put(\"Flamewing\", new MutableOrb(100, 200));\n        initialConstellation.put(\"Frostscale\", new MutableOrb(300, 400));\n        initialConstellation.put(\"Shadowtail\", new MutableOrb(500, 600));\n        \n        ChronomanticDragonTracker tracker = new ChronomanticDragonTracker(initialConstellation);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> updateTask = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    tracker.setOrb(\"Flamewing\", 150 + i * 10, 250 + i * 10);\n                    Thread.sleep(100);\n                    tracker.setOrb(\"Frostscale\", 350 + i * 5, 450 + i * 5);\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> readTask = executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    MutableOrb flamewing = tracker.getOrb(\"Flamewing\");\n                    if (flamewing != null) {\n                        System.out.println(\"Flamewing at: \" + flamewing.getShimmerX() + \", \" + flamewing.getShimmerY());\n                    }\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        updateTask.get();\n        readTask.get();\n        \n        Map<String, MutableOrb> finalConstellations = tracker.getConstellations();\n        for (Map.Entry<String, MutableOrb> entry : finalConstellations.entrySet()) {\n            System.out.println(entry.getKey() + \" final position: \" + \n                             entry.getValue().getShimmerX() + \", \" + \n                             entry.getValue().getShimmerY());\n        }\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableOrb {\n    private int shimmerX;\n    private int shimmerY;\n    \n    public MutableOrb(int shimmerX, int shimmerY) {\n        this.shimmerX = shimmerX;\n        this.shimmerY = shimmerY;\n    }\n    \n    public MutableOrb(MutableOrb other) {\n        this.shimmerX = other.shimmerX;\n        this.shimmerY = other.shimmerY;\n    }\n    \n    public int getShimmerX() {\n        return shimmerX;\n    }\n    \n    public int getShimmerY() {\n        return shimmerY;\n    }\n    \n    public void setShimmerX(int shimmerX) {\n        this.shimmerX = shimmerX;\n    }\n    \n    public void setShimmerY(int shimmerY) {\n        this.shimmerY = shimmerY;\n    }\n}\n\nclass Constellation<K, V> extends HashMap<K, V> {\n    public Constellation() {\n        super();\n    }\n    \n    public Constellation(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass ChronomanticDragonTracker {\n    private final Constellation<String, MutableOrb> constellation;\n    \n    public ChronomanticDragonTracker(Constellation<String, MutableOrb> initialConstellation) {\n        this.constellation = deepClone(initialConstellation);\n    }\n    \n    public synchronized Map<String, MutableOrb> getConstellations() {\n        return Collections.unmodifiableMap(deepClone(constellation));\n    }\n    \n    public synchronized MutableOrb getOrb(String sigil) {\n        MutableOrb orb = constellation.get(sigil);\n        return orb == null ? null : new MutableOrb(orb);\n    }\n    \n    public synchronized void setOrb(String sigil, int shimmerX, int shimmerY) {\n        MutableOrb orb = constellation.get(sigil);\n        if (orb == null) {\n            throw new IllegalArgumentException(\"Sigil not found: \" + sigil);\n        }\n        orb.setShimmerX(shimmerX);\n        orb.setShimmerY(shimmerY);\n    }\n    \n    private static Constellation<String, MutableOrb> deepClone(Constellation<String, MutableOrb> original) {\n        Constellation<String, MutableOrb> cloned = new Constellation<>();\n        for (Map.Entry<String, MutableOrb> entry : original.entrySet()) {\n            cloned.put(entry.getKey(), new MutableOrb(entry.getValue()));\n        }\n        return cloned;\n    }\n}\n\npublic class DragonTrackerApp {\n    public static void main(String[] args) {\n        Constellation<String, MutableOrb> initialConstellation = new Constellation<>();\n        initialConstellation.put(\"Draconius\", new MutableOrb(100, 200));\n        initialConstellation.put(\"Pyraxis\", new MutableOrb(300, 400));\n        initialConstellation.put(\"Glacius\", new MutableOrb(500, 600));\n        \n        ChronomanticDragonTracker tracker = new ChronomanticDragonTracker(initialConstellation);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    tracker.setOrb(\"Draconius\", 100 + i * 10, 200 + i * 20);\n                    Thread.sleep(100);\n                    MutableOrb orb = tracker.getOrb(\"Draconius\");\n                    System.out.println(\"Thread 1 - Draconius: \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    tracker.setOrb(\"Pyraxis\", 300 + i * 15, 400 + i * 25);\n                    Thread.sleep(150);\n                    Map<String, MutableOrb> constellations = tracker.getConstellations();\n                    MutableOrb orb = constellations.get(\"Pyraxis\");\n                    System.out.println(\"Thread 2 - Pyraxis: \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final constellation state:\");\n        Map<String, MutableOrb> finalState = tracker.getConstellations();\n        for (Map.Entry<String, MutableOrb> entry : finalState.entrySet()) {\n            MutableOrb orb = entry.getValue();\n            System.out.println(entry.getKey() + \": \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            false
        ],
        "ground_truth": "import java.util.*;\n\npublic class MonitorVehicleTracker {\nprivate final Map<String, MutablePoint> locations;\n\npublic MonitorVehicleTracker(Map<String, MutablePoint> locations) {\nthis.locations = deepCopy(locations);\n}\n\npublic synchronized Map<String, MutablePoint> getLocations() {\nreturn deepCopy(locations);\n}\n\npublic synchronized MutablePoint getLocation(String id) {\nMutablePoint loc = locations.get(id);\nreturn loc == null ? null : new MutablePoint(loc);\n}\n\npublic synchronized void setLocation(String id, int x, int y) {\nMutablePoint loc = locations.get(id);\nif (loc == null)\nthrow new IllegalArgumentException(\"No such ID: \" + id);\nloc.x = x;\nloc.y = y;\n}\n\nprivate static Map<String, MutablePoint> deepCopy(Map<String, MutablePoint> m) {\nMap<String, MutablePoint> result = new HashMap<>();\nfor (String id : m.keySet())\nresult.put(id, new MutablePoint(m.get(id)));\nreturn Collections.unmodifiableMap(result);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, MutablePoint> initialLocations = new HashMap<>();\ninitialLocations.put(\"car1\", new MutablePoint(0, 0));\ninitialLocations.put(\"car2\", new MutablePoint(10, 10));\n\nMonitorVehicleTracker tracker = new MonitorVehicleTracker(initialLocations);\n\nThread updater = new Thread(() -> {\ntry {\nThread.sleep(500);\ntracker.setLocation(\"car1\", 5, 5);\nSystem.out.println(\"Updated car1 to (5,5)\");\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nThread reader = new Thread(() -> {\ntry {\nThread.sleep(1000);\nMap<String, MutablePoint> snapshot = tracker.getLocations();\nSystem.out.println(\"Current locations:\");\nsnapshot.forEach((id, point) -> System.out.println(id + \": (\" + point.x + \", \" + point.y + \")\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nupdater.start();\nreader.start();\n\nupdater.join();\nreader.join();\n\nSystem.out.println(\"All threads completed.\");\n}\n}\n\nclass MutablePoint {\npublic int x, y;\n\npublic MutablePoint() {\nthis(0, 0);\n}\n\npublic MutablePoint(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\npublic MutablePoint(MutablePoint p) {\nthis(p.x, p.y);\n}\n}",
        "max_depth": "51",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 61.30%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 61.08%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 62.25%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=122831,visited=215354,backtracked=338089,end=164\nsearch:             maxDepth=224,constraints=0\nchoice generators:  thread=122829 (signal=0,lock=21595,sharedRef=70223,threadApi=4883,reschedule=15016), data=0\nheap:               new=494922,released=304277,maxLive=771,gcCycles=330578\ninstructions:       18938170\nmax memory:         1019MB\nloaded code:        classes=151,methods=2540\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 55.12%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 58.51%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 62.16%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=130311,visited=212410,backtracked=342554,end=73\nsearch:             maxDepth=221,constraints=0\nchoice generators:  thread=130310 (signal=0,lock=22922,sharedRef=68249,threadApi=15311,reschedule=14784), data=0\nheap:               new=400483,released=392033,maxLive=767,gcCycles=336728\ninstructions:       15752186\nmax memory:         1019MB\nloaded code:        classes=151,methods=2540\n\n====================================================== search finished",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nDragonTrackerApp.main()\n====================================================== search started: 11/16/25 5:01 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            63.74,
            63.0,
            64.13
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableOrb {\n    private int shimmerX;\n    private int shimmerY;\n    \n    public MutableOrb(int shimmerX, int shimmerY) {\n        this.shimmerX = shimmerX;\n        this.shimmerY = shimmerY;\n    }\n    \n    public MutableOrb(MutableOrb other) {\n        this.shimmerX = other.shimmerX;\n        this.shimmerY = other.shimmerY;\n    }\n    \n    public int getShimmerX() {\n        return shimmerX;\n    }\n    \n    public int getShimmerY() {\n        return shimmerY;\n    }\n    \n    public void setShimmerX(int shimmerX) {\n        this.shimmerX = shimmerX;\n    }\n    \n    public void setShimmerY(int shimmerY) {\n        this.shimmerY = shimmerY;\n    }\n}\n\nclass Constellation<K, V> extends HashMap<K, V> {\n    public Constellation() {\n        super();\n    }\n    \n    public Constellation(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass ChronomanticDragonTracker {\n    private final Constellation<String, MutableOrb> constellation;\n    \n    public ChronomanticDragonTracker(Constellation<String, MutableOrb> initialConstellation) {\n        this.constellation = deepClone(initialConstellation);\n    }\n    \n    public synchronized Map<String, MutableOrb> getConstellations() {\n        return Collections.unmodifiableMap(deepClone(constellation));\n    }\n    \n    public synchronized MutableOrb getOrb(String sigil) {\n        MutableOrb orb = constellation.get(sigil);\n        return orb != null ? new MutableOrb(orb) : null;\n    }\n    \n    public synchronized void setOrb(String sigil, int shimmerX, int shimmerY) {\n        MutableOrb orb = constellation.get(sigil);\n        if (orb == null) {\n            throw new IllegalArgumentException(\"Sigil not present: \" + sigil);\n        }\n        orb.setShimmerX(shimmerX);\n        orb.setShimmerY(shimmerY);\n    }\n    \n    private static Constellation<String, MutableOrb> deepClone(Constellation<String, MutableOrb> original) {\n        Constellation<String, MutableOrb> clone = new Constellation<>();\n        for (Map.Entry<String, MutableOrb> entry : original.entrySet()) {\n            clone.put(entry.getKey(), new MutableOrb(entry.getValue()));\n        }\n        return clone;\n    }\n}\n\npublic class DragonTrackerApp {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Constellation<String, MutableOrb> initialConstellation = new Constellation<>();\n        initialConstellation.put(\"FireDragon\", new MutableOrb(100, 200));\n        initialConstellation.put(\"IceDragon\", new MutableOrb(300, 400));\n        initialConstellation.put(\"WindDragon\", new MutableOrb(500, 600));\n        \n        ChronomanticDragonTracker tracker = new ChronomanticDragonTracker(initialConstellation);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setOrb(\"FireDragon\", 100 + i * 10, 200 + i * 10);\n                MutableOrb orb = tracker.getOrb(\"FireDragon\");\n                System.out.println(\"Thread 1 - FireDragon: \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setOrb(\"IceDragon\", 300 - i * 5, 400 - i * 5);\n                MutableOrb orb = tracker.getOrb(\"IceDragon\");\n                System.out.println(\"Thread 2 - IceDragon: \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Final constellations:\");\n        Map<String, MutableOrb> finalConstellations = tracker.getConstellations();\n        for (Map.Entry<String, MutableOrb> entry : finalConstellations.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + \n                entry.getValue().getShimmerX() + \", \" + entry.getValue().getShimmerY());\n        }\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableOrb {\n    private int shimmerX;\n    private int shimmerY;\n    \n    public MutableOrb(int shimmerX, int shimmerY) {\n        this.shimmerX = shimmerX;\n        this.shimmerY = shimmerY;\n    }\n    \n    public MutableOrb(MutableOrb other) {\n        this.shimmerX = other.shimmerX;\n        this.shimmerY = other.shimmerY;\n    }\n    \n    public int getShimmerX() {\n        return shimmerX;\n    }\n    \n    public int getShimmerY() {\n        return shimmerY;\n    }\n    \n    public void setShimmerX(int shimmerX) {\n        this.shimmerX = shimmerX;\n    }\n    \n    public void setShimmerY(int shimmerY) {\n        this.shimmerY = shimmerY;\n    }\n}\n\nclass Constellation<K, V> extends HashMap<K, V> {\n    public Constellation() {\n        super();\n    }\n    \n    public Constellation(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass ChronomanticDragonTracker {\n    private final Constellation<String, MutableOrb> constellation;\n    \n    public ChronomanticDragonTracker(Constellation<String, MutableOrb> initialConstellation) {\n        this.constellation = deepClone(initialConstellation);\n    }\n    \n    public synchronized Map<String, MutableOrb> getConstellations() {\n        return Collections.unmodifiableMap(deepClone(constellation));\n    }\n    \n    public synchronized MutableOrb getOrb(String sigil) {\n        MutableOrb orb = constellation.get(sigil);\n        return orb == null ? null : new MutableOrb(orb);\n    }\n    \n    public synchronized void setOrb(String sigil, int shimmerX, int shimmerY) {\n        MutableOrb orb = constellation.get(sigil);\n        if (orb == null) {\n            throw new IllegalArgumentException(\"Sigil not found: \" + sigil);\n        }\n        orb.setShimmerX(shimmerX);\n        orb.setShimmerY(shimmerY);\n    }\n    \n    private static Constellation<String, MutableOrb> deepClone(Constellation<String, MutableOrb> original) {\n        Constellation<String, MutableOrb> clone = new Constellation<>();\n        for (Map.Entry<String, MutableOrb> entry : original.entrySet()) {\n            clone.put(entry.getKey(), new MutableOrb(entry.getValue()));\n        }\n        return clone;\n    }\n}\n\npublic class DragonTrackerApp {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Constellation<String, MutableOrb> initialConstellation = new Constellation<>();\n        initialConstellation.put(\"Flamewing\", new MutableOrb(100, 200));\n        initialConstellation.put(\"Frostscale\", new MutableOrb(300, 400));\n        initialConstellation.put(\"Shadowtail\", new MutableOrb(500, 600));\n        \n        ChronomanticDragonTracker tracker = new ChronomanticDragonTracker(initialConstellation);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> updateTask = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    tracker.setOrb(\"Flamewing\", 150 + i * 10, 250 + i * 10);\n                    Thread.sleep(100);\n                    tracker.setOrb(\"Frostscale\", 350 + i * 5, 450 + i * 5);\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> readTask = executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    MutableOrb flamewing = tracker.getOrb(\"Flamewing\");\n                    if (flamewing != null) {\n                        System.out.println(\"Flamewing at: \" + flamewing.getShimmerX() + \", \" + flamewing.getShimmerY());\n                    }\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        updateTask.get();\n        readTask.get();\n        \n        Map<String, MutableOrb> finalConstellations = tracker.getConstellations();\n        for (Map.Entry<String, MutableOrb> entry : finalConstellations.entrySet()) {\n            System.out.println(entry.getKey() + \" final position: \" + \n                             entry.getValue().getShimmerX() + \", \" + \n                             entry.getValue().getShimmerY());\n        }\n        \n        executor.shutdown();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableOrb {\n    private int shimmerX;\n    private int shimmerY;\n    \n    public MutableOrb(int shimmerX, int shimmerY) {\n        this.shimmerX = shimmerX;\n        this.shimmerY = shimmerY;\n    }\n    \n    public MutableOrb(MutableOrb other) {\n        this.shimmerX = other.shimmerX;\n        this.shimmerY = other.shimmerY;\n    }\n    \n    public int getShimmerX() {\n        return shimmerX;\n    }\n    \n    public int getShimmerY() {\n        return shimmerY;\n    }\n    \n    public void setShimmerX(int shimmerX) {\n        this.shimmerX = shimmerX;\n    }\n    \n    public void setShimmerY(int shimmerY) {\n        this.shimmerY = shimmerY;\n    }\n}\n\nclass Constellation<K, V> extends HashMap<K, V> {\n    public Constellation() {\n        super();\n    }\n    \n    public Constellation(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass ChronomanticDragonTracker {\n    private final Constellation<String, MutableOrb> constellation;\n    \n    public ChronomanticDragonTracker(Constellation<String, MutableOrb> initialConstellation) {\n        this.constellation = deepClone(initialConstellation);\n    }\n    \n    public synchronized Map<String, MutableOrb> getConstellations() {\n        return Collections.unmodifiableMap(deepClone(constellation));\n    }\n    \n    public synchronized MutableOrb getOrb(String sigil) {\n        MutableOrb orb = constellation.get(sigil);\n        return orb == null ? null : new MutableOrb(orb);\n    }\n    \n    public synchronized void setOrb(String sigil, int shimmerX, int shimmerY) {\n        MutableOrb orb = constellation.get(sigil);\n        if (orb == null) {\n            throw new IllegalArgumentException(\"Sigil not found: \" + sigil);\n        }\n        orb.setShimmerX(shimmerX);\n        orb.setShimmerY(shimmerY);\n    }\n    \n    private static Constellation<String, MutableOrb> deepClone(Constellation<String, MutableOrb> original) {\n        Constellation<String, MutableOrb> cloned = new Constellation<>();\n        for (Map.Entry<String, MutableOrb> entry : original.entrySet()) {\n            cloned.put(entry.getKey(), new MutableOrb(entry.getValue()));\n        }\n        return cloned;\n    }\n}\n\npublic class DragonTrackerApp {\n    public static void main(String[] args) {\n        Constellation<String, MutableOrb> initialConstellation = new Constellation<>();\n        initialConstellation.put(\"Draconius\", new MutableOrb(100, 200));\n        initialConstellation.put(\"Pyraxis\", new MutableOrb(300, 400));\n        initialConstellation.put(\"Glacius\", new MutableOrb(500, 600));\n        \n        ChronomanticDragonTracker tracker = new ChronomanticDragonTracker(initialConstellation);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    tracker.setOrb(\"Draconius\", 100 + i * 10, 200 + i * 20);\n                    Thread.sleep(100);\n                    MutableOrb orb = tracker.getOrb(\"Draconius\");\n                    System.out.println(\"Thread 1 - Draconius: \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    tracker.setOrb(\"Pyraxis\", 300 + i * 15, 400 + i * 25);\n                    Thread.sleep(150);\n                    Map<String, MutableOrb> constellations = tracker.getConstellations();\n                    MutableOrb orb = constellations.get(\"Pyraxis\");\n                    System.out.println(\"Thread 2 - Pyraxis: \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final constellation state:\");\n        Map<String, MutableOrb> finalState = tracker.getConstellations();\n        for (Map.Entry<String, MutableOrb> entry : finalState.entrySet()) {\n            MutableOrb orb = entry.getValue();\n            System.out.println(entry.getKey() + \": \" + orb.getShimmerX() + \", \" + orb.getShimmerY());\n        }\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Monitor-based vehicle tracker implementation. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe MysticSeahorseTracker class in Java that charts the currents of seahorses using a synchronized bubbleMap. The class should take an initial BubbleMap<String, MutableShell> in its constructor and make a deep copy of it to prevent external tinkering. All public methods must be synchronized to ensure thread safety. Implement a getCurrents() method that returns an unmodifiable deep copy of the entire bubbleMap. Also provide a getShell(String rune) method that returns a new MutableShell copy of the location for the given rune, or null if not found. Include a setShell(String rune, int swirlX, int swirlY) method that updates the coordinates for the specified seahorse and throws an IllegalArgumentException if the rune is not present. Use a private static deepReplicate method to create a new bubbleMap with copies of all MutableShell values. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticSeahorseTracker {\n    private final Map<String, MutableShell> bubbleMap;\n    \n    public MysticSeahorseTracker(Map<String, MutableShell> initialBubbleMap) {\n        this.bubbleMap = deepReplicate(initialBubbleMap);\n    }\n    \n    public synchronized Map<String, MutableShell> getCurrents() {\n        return Collections.unmodifiableMap(deepReplicate(bubbleMap));\n    }\n    \n    public synchronized MutableShell getShell(String rune) {\n        MutableShell shell = bubbleMap.get(rune);\n        return shell == null ? null : new MutableShell(shell.swirlX, shell.swirlY);\n    }\n    \n    public synchronized void setShell(String rune, int swirlX, int swirlY) {\n        if (!bubbleMap.containsKey(rune)) {\n            throw new IllegalArgumentException(\"Rune not present: \" + rune);\n        }\n        bubbleMap.get(rune).swirlX = swirlX;\n        bubbleMap.get(rune).swirlY = swirlY;\n    }\n    \n    private static Map<String, MutableShell> deepReplicate(Map<String, MutableShell> original) {\n        Map<String, MutableShell> copy = new HashMap<>();\n        for (Map.Entry<String, MutableShell> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableShell(entry.getValue().swirlX, entry.getValue().swirlY));\n        }\n        return copy;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutableShell> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new MutableShell(10, 20));\n        initialMap.put(\"beta\", new MutableShell(30, 40));\n        initialMap.put(\"gamma\", new MutableShell(50, 60));\n        \n        MysticSeahorseTracker tracker = new MysticSeahorseTracker(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"alpha\", i * 10, i * 20);\n                MutableShell shell = tracker.getShell(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + shell.swirlX + \", \" + shell.swirlY);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"beta\", i * 5, i * 15);\n                Map<String, MutableShell> currents = tracker.getCurrents();\n                MutableShell betaShell = currents.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaShell.swirlX + \", \" + betaShell.swirlY);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final state:\");\n        Map<String, MutableShell> finalState = tracker.getCurrents();\n        for (Map.Entry<String, MutableShell> entry : finalState.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue().swirlX + \", \" + entry.getValue().swirlY);\n        }\n    }\n}\n\nclass MutableShell {\n    int swirlX;\n    int swirlY;\n    \n    public MutableShell(int swirlX, int swirlY) {\n        this.swirlX = swirlX;\n        this.swirlY = swirlY;\n    }\n}\n\nclass BubbleMap<K, V> extends HashMap<K, V> {\n    public BubbleMap() {\n        super();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticSeahorseTracker {\n    private final Map<String, MutableShell> bubbleMap;\n    \n    public MysticSeahorseTracker(Map<String, MutableShell> initialBubbleMap) {\n        this.bubbleMap = deepReplicate(initialBubbleMap);\n    }\n    \n    public synchronized Map<String, MutableShell> getCurrents() {\n        return Collections.unmodifiableMap(deepReplicate(bubbleMap));\n    }\n    \n    public synchronized MutableShell getShell(String rune) {\n        MutableShell shell = bubbleMap.get(rune);\n        return shell != null ? new MutableShell(shell.swirlX, shell.swirlY) : null;\n    }\n    \n    public synchronized void setShell(String rune, int swirlX, int swirlY) {\n        if (!bubbleMap.containsKey(rune)) {\n            throw new IllegalArgumentException(\"Rune not present: \" + rune);\n        }\n        bubbleMap.get(rune).swirlX = swirlX;\n        bubbleMap.get(rune).swirlY = swirlY;\n    }\n    \n    private static Map<String, MutableShell> deepReplicate(Map<String, MutableShell> original) {\n        Map<String, MutableShell> copy = new HashMap<>();\n        for (Map.Entry<String, MutableShell> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableShell(entry.getValue().swirlX, entry.getValue().swirlY));\n        }\n        return copy;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutableShell> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new MutableShell(10, 20));\n        initialMap.put(\"beta\", new MutableShell(30, 40));\n        initialMap.put(\"gamma\", new MutableShell(50, 60));\n        \n        MysticSeahorseTracker tracker = new MysticSeahorseTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"alpha\", i * 10, i * 20);\n                MutableShell shell = tracker.getShell(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + shell.swirlX + \", \" + shell.swirlY);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"beta\", i * 15, i * 25);\n                Map<String, MutableShell> currents = tracker.getCurrents();\n                MutableShell betaShell = currents.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaShell.swirlX + \", \" + betaShell.swirlY);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final state:\");\n        Map<String, MutableShell> finalState = tracker.getCurrents();\n        for (Map.Entry<String, MutableShell> entry : finalState.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue().swirlX + \", \" + entry.getValue().swirlY);\n        }\n    }\n}\n\nclass MutableShell {\n    int swirlX;\n    int swirlY;\n    \n    MutableShell(int swirlX, int swirlY) {\n        this.swirlX = swirlX;\n        this.swirlY = swirlY;\n    }\n}\n\nclass BubbleMap<K, V> extends HashMap<K, V> {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableShell {\n    private int swirlX;\n    private int swirlY;\n    \n    public MutableShell(int swirlX, int swirlY) {\n        this.swirlX = swirlX;\n        this.swirlY = swirlY;\n    }\n    \n    public MutableShell(MutableShell other) {\n        this.swirlX = other.swirlX;\n        this.swirlY = other.swirlY;\n    }\n    \n    public int getSwirlX() {\n        return swirlX;\n    }\n    \n    public int getSwirlY() {\n        return swirlY;\n    }\n    \n    public void setSwirlX(int swirlX) {\n        this.swirlX = swirlX;\n    }\n    \n    public void setSwirlY(int swirlY) {\n        this.swirlY = swirlY;\n    }\n}\n\nclass BubbleMap<K, V> extends HashMap<K, V> {\n    public BubbleMap() {\n        super();\n    }\n    \n    public BubbleMap(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass MysticSeahorseTracker {\n    private final BubbleMap<String, MutableShell> bubbleMap;\n    \n    public MysticSeahorseTracker(BubbleMap<String, MutableShell> initialMap) {\n        this.bubbleMap = deepReplicate(initialMap);\n    }\n    \n    public synchronized BubbleMap<String, MutableShell> getCurrents() {\n        return Collections.unmodifiableMap(deepReplicate(bubbleMap));\n    }\n    \n    public synchronized MutableShell getShell(String rune) {\n        MutableShell shell = bubbleMap.get(rune);\n        return shell == null ? null : new MutableShell(shell);\n    }\n    \n    public synchronized void setShell(String rune, int swirlX, int swirlY) {\n        MutableShell shell = bubbleMap.get(rune);\n        if (shell == null) {\n            throw new IllegalArgumentException(\"Rune not found: \" + rune);\n        }\n        shell.setSwirlX(swirlX);\n        shell.setSwirlY(swirlY);\n    }\n    \n    private static BubbleMap<String, MutableShell> deepReplicate(BubbleMap<String, MutableShell> original) {\n        BubbleMap<String, MutableShell> copy = new BubbleMap<>();\n        for (Map.Entry<String, MutableShell> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableShell(entry.getValue()));\n        }\n        return copy;\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        BubbleMap<String, MutableShell> initialMap = new BubbleMap<>();\n        initialMap.put(\"seahorse1\", new MutableShell(10, 20));\n        initialMap.put(\"seahorse2\", new MutableShell(30, 40));\n        initialMap.put(\"seahorse3\", new MutableShell(50, 60));\n        \n        MysticSeahorseTracker tracker = new MysticSeahorseTracker(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"seahorse1\", i * 10, i * 20);\n                MutableShell shell = tracker.getShell(\"seahorse1\");\n                System.out.println(\"Thread 1 - seahorse1: \" + shell.getSwirlX() + \", \" + shell.getSwirlY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"seahorse2\", i * 15, i * 25);\n                MutableShell shell = tracker.getShell(\"seahorse2\");\n                System.out.println(\"Thread 2 - seahorse2: \" + shell.getSwirlX() + \", \" + shell.getSwirlY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Final state:\");\n        BubbleMap<String, MutableShell> finalMap = tracker.getCurrents();\n        for (Map.Entry<String, MutableShell> entry : finalMap.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + \n                entry.getValue().getSwirlX() + \", \" + entry.getValue().getSwirlY());\n        }\n        \n        executor.shutdown();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            false
        ],
        "ground_truth": "import java.util.*;\n\npublic class MonitorVehicleTracker {\nprivate final Map<String, MutablePoint> locations;\n\npublic MonitorVehicleTracker(Map<String, MutablePoint> locations) {\nthis.locations = deepCopy(locations);\n}\n\npublic synchronized Map<String, MutablePoint> getLocations() {\nreturn deepCopy(locations);\n}\n\npublic synchronized MutablePoint getLocation(String id) {\nMutablePoint loc = locations.get(id);\nreturn loc == null ? null : new MutablePoint(loc);\n}\n\npublic synchronized void setLocation(String id, int x, int y) {\nMutablePoint loc = locations.get(id);\nif (loc == null)\nthrow new IllegalArgumentException(\"No such ID: \" + id);\nloc.x = x;\nloc.y = y;\n}\n\nprivate static Map<String, MutablePoint> deepCopy(Map<String, MutablePoint> m) {\nMap<String, MutablePoint> result = new HashMap<>();\nfor (String id : m.keySet())\nresult.put(id, new MutablePoint(m.get(id)));\nreturn Collections.unmodifiableMap(result);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, MutablePoint> initialLocations = new HashMap<>();\ninitialLocations.put(\"car1\", new MutablePoint(0, 0));\ninitialLocations.put(\"car2\", new MutablePoint(10, 10));\n\nMonitorVehicleTracker tracker = new MonitorVehicleTracker(initialLocations);\n\nThread updater = new Thread(() -> {\ntry {\nThread.sleep(500);\ntracker.setLocation(\"car1\", 5, 5);\nSystem.out.println(\"Updated car1 to (5,5)\");\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nThread reader = new Thread(() -> {\ntry {\nThread.sleep(1000);\nMap<String, MutablePoint> snapshot = tracker.getLocations();\nSystem.out.println(\"Current locations:\");\nsnapshot.forEach((id, point) -> System.out.println(id + \": (\" + point.x + \", \" + point.y + \")\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nupdater.start();\nreader.start();\n\nupdater.join();\nreader.join();\n\nSystem.out.println(\"All threads completed.\");\n}\n}\n\nclass MutablePoint {\npublic int x, y;\n\npublic MutablePoint() {\nthis(0, 0);\n}\n\npublic MutablePoint(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\npublic MutablePoint(MutablePoint p) {\nthis(p.x, p.y);\n}\n}",
        "max_depth": "51",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 39.99%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 23.70%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.24%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=76363,visited=50778,backtracked=126714,end=27808\nsearch:             maxDepth=510,constraints=4091\nchoice generators:  thread=73680 (signal=0,lock=32,sharedRef=30359,threadApi=12,reschedule=38149), data=0\nheap:               new=1694909,released=2749750,maxLive=777,gcCycles=127140\ninstructions:       105011818\nmax memory:         1012MB\nloaded code:        classes=149,methods=2532\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 23.81%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.32%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=77370,visited=51453,backtracked=128315,end=28063\nsearch:             maxDepth=510,constraints=4220\nchoice generators:  thread=74618 (signal=0,lock=32,sharedRef=30890,threadApi=12,reschedule=38489), data=0\nheap:               new=1710522,released=2775729,maxLive=777,gcCycles=128822\ninstructions:       106039070\nmax memory:         1013MB\nloaded code:        classes=149,methods=2532\n\n====================================================== search finished",
            "./temp_compile/Main.java:53: error: incompatible types: no instance(s) of type variable(s) K,V exist so that Map<K,V> conforms to BubbleMap<String,MutableShell>\n        return Collections.unmodifiableMap(deepReplicate(bubbleMap));\n                                          ^\n  where K,V are type-variables:\n    K extends Object declared in method <K,V>unmodifiableMap(Map<? extends K,? extends V>)\n    V extends Object declared in method <K,V>unmodifiableMap(Map<? extends K,? extends V>)\n1 error"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "syntax error"
        ],
        "codebleu_score": [
            60.14,
            59.95,
            63.05
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticSeahorseTracker {\n    private final Map<String, MutableShell> bubbleMap;\n    \n    public MysticSeahorseTracker(Map<String, MutableShell> initialBubbleMap) {\n        this.bubbleMap = deepReplicate(initialBubbleMap);\n    }\n    \n    public synchronized Map<String, MutableShell> getCurrents() {\n        return Collections.unmodifiableMap(deepReplicate(bubbleMap));\n    }\n    \n    public synchronized MutableShell getShell(String rune) {\n        MutableShell shell = bubbleMap.get(rune);\n        return shell == null ? null : new MutableShell(shell.swirlX, shell.swirlY);\n    }\n    \n    public synchronized void setShell(String rune, int swirlX, int swirlY) {\n        if (!bubbleMap.containsKey(rune)) {\n            throw new IllegalArgumentException(\"Rune not present: \" + rune);\n        }\n        bubbleMap.get(rune).swirlX = swirlX;\n        bubbleMap.get(rune).swirlY = swirlY;\n    }\n    \n    private static Map<String, MutableShell> deepReplicate(Map<String, MutableShell> original) {\n        Map<String, MutableShell> copy = new HashMap<>();\n        for (Map.Entry<String, MutableShell> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableShell(entry.getValue().swirlX, entry.getValue().swirlY));\n        }\n        return copy;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutableShell> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new MutableShell(10, 20));\n        initialMap.put(\"beta\", new MutableShell(30, 40));\n        initialMap.put(\"gamma\", new MutableShell(50, 60));\n        \n        MysticSeahorseTracker tracker = new MysticSeahorseTracker(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"alpha\", i * 10, i * 20);\n                MutableShell shell = tracker.getShell(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + shell.swirlX + \", \" + shell.swirlY);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"beta\", i * 5, i * 15);\n                Map<String, MutableShell> currents = tracker.getCurrents();\n                MutableShell betaShell = currents.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaShell.swirlX + \", \" + betaShell.swirlY);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final state:\");\n        Map<String, MutableShell> finalState = tracker.getCurrents();\n        for (Map.Entry<String, MutableShell> entry : finalState.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue().swirlX + \", \" + entry.getValue().swirlY);\n        }\n    }\n}\n\nclass MutableShell {\n    int swirlX;\n    int swirlY;\n    \n    public MutableShell(int swirlX, int swirlY) {\n        this.swirlX = swirlX;\n        this.swirlY = swirlY;\n    }\n}\n\nclass BubbleMap<K, V> extends HashMap<K, V> {\n    public BubbleMap() {\n        super();\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class MysticSeahorseTracker {\n    private final Map<String, MutableShell> bubbleMap;\n    \n    public MysticSeahorseTracker(Map<String, MutableShell> initialBubbleMap) {\n        this.bubbleMap = deepReplicate(initialBubbleMap);\n    }\n    \n    public synchronized Map<String, MutableShell> getCurrents() {\n        return Collections.unmodifiableMap(deepReplicate(bubbleMap));\n    }\n    \n    public synchronized MutableShell getShell(String rune) {\n        MutableShell shell = bubbleMap.get(rune);\n        return shell != null ? new MutableShell(shell.swirlX, shell.swirlY) : null;\n    }\n    \n    public synchronized void setShell(String rune, int swirlX, int swirlY) {\n        if (!bubbleMap.containsKey(rune)) {\n            throw new IllegalArgumentException(\"Rune not present: \" + rune);\n        }\n        bubbleMap.get(rune).swirlX = swirlX;\n        bubbleMap.get(rune).swirlY = swirlY;\n    }\n    \n    private static Map<String, MutableShell> deepReplicate(Map<String, MutableShell> original) {\n        Map<String, MutableShell> copy = new HashMap<>();\n        for (Map.Entry<String, MutableShell> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableShell(entry.getValue().swirlX, entry.getValue().swirlY));\n        }\n        return copy;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutableShell> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new MutableShell(10, 20));\n        initialMap.put(\"beta\", new MutableShell(30, 40));\n        initialMap.put(\"gamma\", new MutableShell(50, 60));\n        \n        MysticSeahorseTracker tracker = new MysticSeahorseTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"alpha\", i * 10, i * 20);\n                MutableShell shell = tracker.getShell(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + shell.swirlX + \", \" + shell.swirlY);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"beta\", i * 15, i * 25);\n                Map<String, MutableShell> currents = tracker.getCurrents();\n                MutableShell betaShell = currents.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaShell.swirlX + \", \" + betaShell.swirlY);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final state:\");\n        Map<String, MutableShell> finalState = tracker.getCurrents();\n        for (Map.Entry<String, MutableShell> entry : finalState.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue().swirlX + \", \" + entry.getValue().swirlY);\n        }\n    }\n}\n\nclass MutableShell {\n    int swirlX;\n    int swirlY;\n    \n    MutableShell(int swirlX, int swirlY) {\n        this.swirlX = swirlX;\n        this.swirlY = swirlY;\n    }\n}\n\nclass BubbleMap<K, V> extends HashMap<K, V> {\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableShell {\n    private int swirlX;\n    private int swirlY;\n    \n    public MutableShell(int swirlX, int swirlY) {\n        this.swirlX = swirlX;\n        this.swirlY = swirlY;\n    }\n    \n    public MutableShell(MutableShell other) {\n        this.swirlX = other.swirlX;\n        this.swirlY = other.swirlY;\n    }\n    \n    public int getSwirlX() {\n        return swirlX;\n    }\n    \n    public int getSwirlY() {\n        return swirlY;\n    }\n    \n    public void setSwirlX(int swirlX) {\n        this.swirlX = swirlX;\n    }\n    \n    public void setSwirlY(int swirlY) {\n        this.swirlY = swirlY;\n    }\n}\n\nclass BubbleMap<K, V> extends HashMap<K, V> {\n    public BubbleMap() {\n        super();\n    }\n    \n    public BubbleMap(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass MysticSeahorseTracker {\n    private final BubbleMap<String, MutableShell> bubbleMap;\n    \n    public MysticSeahorseTracker(BubbleMap<String, MutableShell> initialMap) {\n        this.bubbleMap = deepReplicate(initialMap);\n    }\n    \n    public synchronized BubbleMap<String, MutableShell> getCurrents() {\n        return Collections.unmodifiableMap(deepReplicate(bubbleMap));\n    }\n    \n    public synchronized MutableShell getShell(String rune) {\n        MutableShell shell = bubbleMap.get(rune);\n        return shell == null ? null : new MutableShell(shell);\n    }\n    \n    public synchronized void setShell(String rune, int swirlX, int swirlY) {\n        MutableShell shell = bubbleMap.get(rune);\n        if (shell == null) {\n            throw new IllegalArgumentException(\"Rune not found: \" + rune);\n        }\n        shell.setSwirlX(swirlX);\n        shell.setSwirlY(swirlY);\n    }\n    \n    private static BubbleMap<String, MutableShell> deepReplicate(BubbleMap<String, MutableShell> original) {\n        BubbleMap<String, MutableShell> copy = new BubbleMap<>();\n        for (Map.Entry<String, MutableShell> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableShell(entry.getValue()));\n        }\n        return copy;\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        BubbleMap<String, MutableShell> initialMap = new BubbleMap<>();\n        initialMap.put(\"seahorse1\", new MutableShell(10, 20));\n        initialMap.put(\"seahorse2\", new MutableShell(30, 40));\n        initialMap.put(\"seahorse3\", new MutableShell(50, 60));\n        \n        MysticSeahorseTracker tracker = new MysticSeahorseTracker(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"seahorse1\", i * 10, i * 20);\n                MutableShell shell = tracker.getShell(\"seahorse1\");\n                System.out.println(\"Thread 1 - seahorse1: \" + shell.getSwirlX() + \", \" + shell.getSwirlY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setShell(\"seahorse2\", i * 15, i * 25);\n                MutableShell shell = tracker.getShell(\"seahorse2\");\n                System.out.println(\"Thread 2 - seahorse2: \" + shell.getSwirlX() + \", \" + shell.getSwirlY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Final state:\");\n        BubbleMap<String, MutableShell> finalMap = tracker.getCurrents();\n        for (Map.Entry<String, MutableShell> entry : finalMap.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + \n                entry.getValue().getSwirlX() + \", \" + entry.getValue().getSwirlY());\n        }\n        \n        executor.shutdown();\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Monitor-based vehicle tracker implementation. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe CelestialGriffinTracker class in Java that monitors the flutters of griffins using a synchronized starlightMap. The class should take an initial StarlightMap<String, MutableGem> in its constructor and make a deep copy of it to prevent external interference. All public methods must be synchronized to ensure thread safety. Implement a getStarlights() method that returns an unmodifiable deep copy of the entire starlightMap. Also provide a getGem(String rune) method that returns a new MutableGem copy of the location for the given rune, or null if not found. Include a setGem(String rune, int glowX, int glowY) method that updates the coordinates for the specified griffin and throws an IllegalArgumentException if the rune is not present. Use a private static deepForge method to create a new starlightMap with copies of all MutableGem values. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class CelestialGriffinTracker {\n    private final Map<String, MutableGem> starlightMap;\n\n    public CelestialGriffinTracker(Map<String, MutableGem> initialMap) {\n        this.starlightMap = deepForge(initialMap);\n    }\n\n    public synchronized Map<String, MutableGem> getStarlights() {\n        return Collections.unmodifiableMap(deepForge(starlightMap));\n    }\n\n    public synchronized MutableGem getGem(String rune) {\n        MutableGem gem = starlightMap.get(rune);\n        return gem == null ? null : new MutableGem(gem.getGlowX(), gem.getGlowY());\n    }\n\n    public synchronized void setGem(String rune, int glowX, int glowY) {\n        MutableGem gem = starlightMap.get(rune);\n        if (gem == null) {\n            throw new IllegalArgumentException(\"Rune not present: \" + rune);\n        }\n        gem.setGlowX(glowX);\n        gem.setGlowY(glowY);\n    }\n\n    private static Map<String, MutableGem> deepForge(Map<String, MutableGem> original) {\n        Map<String, MutableGem> copy = new HashMap<>();\n        for (Map.Entry<String, MutableGem> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableGem(entry.getValue().getGlowX(), entry.getValue().getGlowY()));\n        }\n        return copy;\n    }\n\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutableGem> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new MutableGem(10, 20));\n        initialMap.put(\"beta\", new MutableGem(30, 40));\n        initialMap.put(\"gamma\", new MutableGem(50, 60));\n\n        CelestialGriffinTracker tracker = new CelestialGriffinTracker(initialMap);\n\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        Future<Void> future1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"alpha\", i * 10, i * 20);\n                MutableGem gem = tracker.getGem(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + gem.getGlowX() + \", \" + gem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n\n        Future<Void> future2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"beta\", i * 15, i * 25);\n                Map<String, MutableGem> allGems = tracker.getStarlights();\n                MutableGem betaGem = allGems.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaGem.getGlowX() + \", \" + betaGem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n\n        future1.get();\n        future2.get();\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n\n        System.out.println(\"Final state:\");\n        Map<String, MutableGem> finalState = tracker.getStarlights();\n        for (Map.Entry<String, MutableGem> entry : finalState.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue().getGlowX() + \", \" + entry.getValue().getGlowY());\n        }\n    }\n}\n\nclass MutableGem {\n    private int glowX;\n    private int glowY;\n\n    public MutableGem(int glowX, int glowY) {\n        this.glowX = glowX;\n        this.glowY = glowY;\n    }\n\n    public int getGlowX() {\n        return glowX;\n    }\n\n    public void setGlowX(int glowX) {\n        this.glowX = glowX;\n    }\n\n    public int getGlowY() {\n        return glowY;\n    }\n\n    public void setGlowY(int glowY) {\n        this.glowY = glowY;\n    }\n}\n\ninterface StarlightMap<K, V> extends Map<K, V> {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableGem {\n    private int glowX;\n    private int glowY;\n    \n    public MutableGem(int glowX, int glowY) {\n        this.glowX = glowX;\n        this.glowY = glowY;\n    }\n    \n    public MutableGem(MutableGem other) {\n        this.glowX = other.glowX;\n        this.glowY = other.glowY;\n    }\n    \n    public int getGlowX() {\n        return glowX;\n    }\n    \n    public int getGlowY() {\n        return glowY;\n    }\n    \n    public void setGlowX(int glowX) {\n        this.glowX = glowX;\n    }\n    \n    public void setGlowY(int glowY) {\n        this.glowY = glowY;\n    }\n}\n\nclass StarlightMap<K, V> extends HashMap<K, V> {\n    public StarlightMap() {\n        super();\n    }\n    \n    public StarlightMap(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass CelestialGriffinTracker {\n    private final StarlightMap<String, MutableGem> starlightMap;\n    \n    public CelestialGriffinTracker(StarlightMap<String, MutableGem> initialMap) {\n        this.starlightMap = deepForge(initialMap);\n    }\n    \n    private static StarlightMap<String, MutableGem> deepForge(StarlightMap<String, MutableGem> source) {\n        StarlightMap<String, MutableGem> copy = new StarlightMap<>();\n        for (Map.Entry<String, MutableGem> entry : source.entrySet()) {\n            copy.put(entry.getKey(), new MutableGem(entry.getValue()));\n        }\n        return copy;\n    }\n    \n    public synchronized Map<String, MutableGem> getStarlights() {\n        Map<String, MutableGem> deepCopy = new HashMap<>();\n        for (Map.Entry<String, MutableGem> entry : starlightMap.entrySet()) {\n            deepCopy.put(entry.getKey(), new MutableGem(entry.getValue()));\n        }\n        return Collections.unmodifiableMap(deepCopy);\n    }\n    \n    public synchronized MutableGem getGem(String rune) {\n        MutableGem gem = starlightMap.get(rune);\n        return gem != null ? new MutableGem(gem) : null;\n    }\n    \n    public synchronized void setGem(String rune, int glowX, int glowY) {\n        MutableGem gem = starlightMap.get(rune);\n        if (gem == null) {\n            throw new IllegalArgumentException(\"Rune not present: \" + rune);\n        }\n        gem.setGlowX(glowX);\n        gem.setGlowY(glowY);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        StarlightMap<String, MutableGem> initialMap = new StarlightMap<>();\n        initialMap.put(\"alpha\", new MutableGem(10, 20));\n        initialMap.put(\"beta\", new MutableGem(30, 40));\n        initialMap.put(\"gamma\", new MutableGem(50, 60));\n        \n        CelestialGriffinTracker tracker = new CelestialGriffinTracker(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"alpha\", i * 10, i * 20);\n                MutableGem gem = tracker.getGem(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + gem.getGlowX() + \", \" + gem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"beta\", i * 15, i * 25);\n                Map<String, MutableGem> allGems = tracker.getStarlights();\n                MutableGem betaGem = allGems.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaGem.getGlowX() + \", \" + betaGem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final state:\");\n        Map<String, MutableGem> finalMap = tracker.getStarlights();\n        for (Map.Entry<String, MutableGem> entry : finalMap.entrySet()) {\n            MutableGem gem = entry.getValue();\n            System.out.println(entry.getKey() + \": \" + gem.getGlowX() + \", \" + gem.getGlowY());\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class CelestialGriffinTracker {\n    private final Map<String, MutableGem> starlightMap;\n    \n    public CelestialGriffinTracker(Map<String, MutableGem> initialMap) {\n        this.starlightMap = deepForge(initialMap);\n    }\n    \n    public synchronized Map<String, MutableGem> getStarlights() {\n        return Collections.unmodifiableMap(deepForge(starlightMap));\n    }\n    \n    public synchronized MutableGem getGem(String rune) {\n        MutableGem gem = starlightMap.get(rune);\n        return gem != null ? new MutableGem(gem.getGlowX(), gem.getGlowY()) : null;\n    }\n    \n    public synchronized void setGem(String rune, int glowX, int glowY) {\n        if (!starlightMap.containsKey(rune)) {\n            throw new IllegalArgumentException(\"Rune not found: \" + rune);\n        }\n        starlightMap.get(rune).setGlowX(glowX);\n        starlightMap.get(rune).setGlowY(glowY);\n    }\n    \n    private static Map<String, MutableGem> deepForge(Map<String, MutableGem> original) {\n        Map<String, MutableGem> copy = new HashMap<>();\n        for (Map.Entry<String, MutableGem> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableGem(entry.getValue().getGlowX(), entry.getValue().getGlowY()));\n        }\n        return copy;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutableGem> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new MutableGem(10, 20));\n        initialMap.put(\"beta\", new MutableGem(30, 40));\n        initialMap.put(\"gamma\", new MutableGem(50, 60));\n        \n        CelestialGriffinTracker tracker = new CelestialGriffinTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"alpha\", i * 10, i * 20);\n                MutableGem gem = tracker.getGem(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + gem.getGlowX() + \", \" + gem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"beta\", i * 5, i * 15);\n                Map<String, MutableGem> allGems = tracker.getStarlights();\n                MutableGem betaGem = allGems.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaGem.getGlowX() + \", \" + betaGem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final state:\");\n        Map<String, MutableGem> finalMap = tracker.getStarlights();\n        for (Map.Entry<String, MutableGem> entry : finalMap.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue().getGlowX() + \", \" + entry.getValue().getGlowY());\n        }\n    }\n}\n\nclass MutableGem {\n    private int glowX;\n    private int glowY;\n    \n    public MutableGem(int glowX, int glowY) {\n        this.glowX = glowX;\n        this.glowY = glowY;\n    }\n    \n    public int getGlowX() {\n        return glowX;\n    }\n    \n    public void setGlowX(int glowX) {\n        this.glowX = glowX;\n    }\n    \n    public int getGlowY() {\n        return glowY;\n    }\n    \n    public void setGlowY(int glowY) {\n        this.glowY = glowY;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\npublic class MonitorVehicleTracker {\nprivate final Map<String, MutablePoint> locations;\n\npublic MonitorVehicleTracker(Map<String, MutablePoint> locations) {\nthis.locations = deepCopy(locations);\n}\n\npublic synchronized Map<String, MutablePoint> getLocations() {\nreturn deepCopy(locations);\n}\n\npublic synchronized MutablePoint getLocation(String id) {\nMutablePoint loc = locations.get(id);\nreturn loc == null ? null : new MutablePoint(loc);\n}\n\npublic synchronized void setLocation(String id, int x, int y) {\nMutablePoint loc = locations.get(id);\nif (loc == null)\nthrow new IllegalArgumentException(\"No such ID: \" + id);\nloc.x = x;\nloc.y = y;\n}\n\nprivate static Map<String, MutablePoint> deepCopy(Map<String, MutablePoint> m) {\nMap<String, MutablePoint> result = new HashMap<>();\nfor (String id : m.keySet())\nresult.put(id, new MutablePoint(m.get(id)));\nreturn Collections.unmodifiableMap(result);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, MutablePoint> initialLocations = new HashMap<>();\ninitialLocations.put(\"car1\", new MutablePoint(0, 0));\ninitialLocations.put(\"car2\", new MutablePoint(10, 10));\n\nMonitorVehicleTracker tracker = new MonitorVehicleTracker(initialLocations);\n\nThread updater = new Thread(() -> {\ntry {\nThread.sleep(500);\ntracker.setLocation(\"car1\", 5, 5);\nSystem.out.println(\"Updated car1 to (5,5)\");\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nThread reader = new Thread(() -> {\ntry {\nThread.sleep(1000);\nMap<String, MutablePoint> snapshot = tracker.getLocations();\nSystem.out.println(\"Current locations:\");\nsnapshot.forEach((id, point) -> System.out.println(id + \": (\" + point.x + \", \" + point.y + \")\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nupdater.start();\nreader.start();\n\nupdater.join();\nreader.join();\n\nSystem.out.println(\"All threads completed.\");\n}\n}\n\nclass MutablePoint {\npublic int x, y;\n\npublic MutablePoint() {\nthis(0, 0);\n}\n\npublic MutablePoint(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\npublic MutablePoint(MutablePoint p) {\nthis(p.x, p.y);\n}\n}",
        "max_depth": "51",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 24.12%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.30%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=75219,visited=50151,backtracked=124867,end=27428\nsearch:             maxDepth=510,constraints=3848\nchoice generators:  thread=72614 (signal=0,lock=31,sharedRef=29646,threadApi=12,reschedule=38019), data=0\nheap:               new=1676521,released=2715225,maxLive=777,gcCycles=125369\ninstructions:       104876594\nmax memory:         1014MB\nloaded code:        classes=149,methods=2536\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 39.84%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 23.82%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.16%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=78042,visited=51997,backtracked=129531,end=28754\nsearch:             maxDepth=510,constraints=3857\nchoice generators:  thread=75560 (signal=0,lock=32,sharedRef=30758,threadApi=12,reschedule=39436), data=0\nheap:               new=1746294,released=2836822,maxLive=783,gcCycles=130038\ninstructions:       107189049\nmax memory:         1013MB\nloaded code:        classes=151,methods=2540\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 39.86%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 23.73%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 30.89%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=76003,visited=50158,backtracked=125683,end=27818\nsearch:             maxDepth=510,constraints=4082\nchoice generators:  thread=73326 (signal=0,lock=32,sharedRef=30119,threadApi=12,reschedule=38027), data=0\nheap:               new=1690621,released=2747753,maxLive=777,gcCycles=126160\ninstructions:       105678733\nmax memory:         1014MB\nloaded code:        classes=149,methods=2536\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            59.42,
            64.28,
            59.95
        ],
        "llm_output": [
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class CelestialGriffinTracker {\n    private final Map<String, MutableGem> starlightMap;\n\n    public CelestialGriffinTracker(Map<String, MutableGem> initialMap) {\n        this.starlightMap = deepForge(initialMap);\n    }\n\n    public synchronized Map<String, MutableGem> getStarlights() {\n        return Collections.unmodifiableMap(deepForge(starlightMap));\n    }\n\n    public synchronized MutableGem getGem(String rune) {\n        MutableGem gem = starlightMap.get(rune);\n        return gem == null ? null : new MutableGem(gem.getGlowX(), gem.getGlowY());\n    }\n\n    public synchronized void setGem(String rune, int glowX, int glowY) {\n        MutableGem gem = starlightMap.get(rune);\n        if (gem == null) {\n            throw new IllegalArgumentException(\"Rune not present: \" + rune);\n        }\n        gem.setGlowX(glowX);\n        gem.setGlowY(glowY);\n    }\n\n    private static Map<String, MutableGem> deepForge(Map<String, MutableGem> original) {\n        Map<String, MutableGem> copy = new HashMap<>();\n        for (Map.Entry<String, MutableGem> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableGem(entry.getValue().getGlowX(), entry.getValue().getGlowY()));\n        }\n        return copy;\n    }\n\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutableGem> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new MutableGem(10, 20));\n        initialMap.put(\"beta\", new MutableGem(30, 40));\n        initialMap.put(\"gamma\", new MutableGem(50, 60));\n\n        CelestialGriffinTracker tracker = new CelestialGriffinTracker(initialMap);\n\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        Future<Void> future1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"alpha\", i * 10, i * 20);\n                MutableGem gem = tracker.getGem(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + gem.getGlowX() + \", \" + gem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n\n        Future<Void> future2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"beta\", i * 15, i * 25);\n                Map<String, MutableGem> allGems = tracker.getStarlights();\n                MutableGem betaGem = allGems.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaGem.getGlowX() + \", \" + betaGem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n\n        future1.get();\n        future2.get();\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n\n        System.out.println(\"Final state:\");\n        Map<String, MutableGem> finalState = tracker.getStarlights();\n        for (Map.Entry<String, MutableGem> entry : finalState.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue().getGlowX() + \", \" + entry.getValue().getGlowY());\n        }\n    }\n}\n\nclass MutableGem {\n    private int glowX;\n    private int glowY;\n\n    public MutableGem(int glowX, int glowY) {\n        this.glowX = glowX;\n        this.glowY = glowY;\n    }\n\n    public int getGlowX() {\n        return glowX;\n    }\n\n    public void setGlowX(int glowX) {\n        this.glowX = glowX;\n    }\n\n    public int getGlowY() {\n        return glowY;\n    }\n\n    public void setGlowY(int glowY) {\n        this.glowY = glowY;\n    }\n}\n\ninterface StarlightMap<K, V> extends Map<K, V> {\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\nclass MutableGem {\n    private int glowX;\n    private int glowY;\n    \n    public MutableGem(int glowX, int glowY) {\n        this.glowX = glowX;\n        this.glowY = glowY;\n    }\n    \n    public MutableGem(MutableGem other) {\n        this.glowX = other.glowX;\n        this.glowY = other.glowY;\n    }\n    \n    public int getGlowX() {\n        return glowX;\n    }\n    \n    public int getGlowY() {\n        return glowY;\n    }\n    \n    public void setGlowX(int glowX) {\n        this.glowX = glowX;\n    }\n    \n    public void setGlowY(int glowY) {\n        this.glowY = glowY;\n    }\n}\n\nclass StarlightMap<K, V> extends HashMap<K, V> {\n    public StarlightMap() {\n        super();\n    }\n    \n    public StarlightMap(Map<K, V> map) {\n        super(map);\n    }\n}\n\nclass CelestialGriffinTracker {\n    private final StarlightMap<String, MutableGem> starlightMap;\n    \n    public CelestialGriffinTracker(StarlightMap<String, MutableGem> initialMap) {\n        this.starlightMap = deepForge(initialMap);\n    }\n    \n    private static StarlightMap<String, MutableGem> deepForge(StarlightMap<String, MutableGem> source) {\n        StarlightMap<String, MutableGem> copy = new StarlightMap<>();\n        for (Map.Entry<String, MutableGem> entry : source.entrySet()) {\n            copy.put(entry.getKey(), new MutableGem(entry.getValue()));\n        }\n        return copy;\n    }\n    \n    public synchronized Map<String, MutableGem> getStarlights() {\n        Map<String, MutableGem> deepCopy = new HashMap<>();\n        for (Map.Entry<String, MutableGem> entry : starlightMap.entrySet()) {\n            deepCopy.put(entry.getKey(), new MutableGem(entry.getValue()));\n        }\n        return Collections.unmodifiableMap(deepCopy);\n    }\n    \n    public synchronized MutableGem getGem(String rune) {\n        MutableGem gem = starlightMap.get(rune);\n        return gem != null ? new MutableGem(gem) : null;\n    }\n    \n    public synchronized void setGem(String rune, int glowX, int glowY) {\n        MutableGem gem = starlightMap.get(rune);\n        if (gem == null) {\n            throw new IllegalArgumentException(\"Rune not present: \" + rune);\n        }\n        gem.setGlowX(glowX);\n        gem.setGlowY(glowY);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        StarlightMap<String, MutableGem> initialMap = new StarlightMap<>();\n        initialMap.put(\"alpha\", new MutableGem(10, 20));\n        initialMap.put(\"beta\", new MutableGem(30, 40));\n        initialMap.put(\"gamma\", new MutableGem(50, 60));\n        \n        CelestialGriffinTracker tracker = new CelestialGriffinTracker(initialMap);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"alpha\", i * 10, i * 20);\n                MutableGem gem = tracker.getGem(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + gem.getGlowX() + \", \" + gem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"beta\", i * 15, i * 25);\n                Map<String, MutableGem> allGems = tracker.getStarlights();\n                MutableGem betaGem = allGems.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaGem.getGlowX() + \", \" + betaGem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final state:\");\n        Map<String, MutableGem> finalMap = tracker.getStarlights();\n        for (Map.Entry<String, MutableGem> entry : finalMap.entrySet()) {\n            MutableGem gem = entry.getValue();\n            System.out.println(entry.getKey() + \": \" + gem.getGlowX() + \", \" + gem.getGlowY());\n        }\n    }\n}\n```",
            "```java\nimport java.util.*;\nimport java.util.concurrent.*;\n\npublic class CelestialGriffinTracker {\n    private final Map<String, MutableGem> starlightMap;\n    \n    public CelestialGriffinTracker(Map<String, MutableGem> initialMap) {\n        this.starlightMap = deepForge(initialMap);\n    }\n    \n    public synchronized Map<String, MutableGem> getStarlights() {\n        return Collections.unmodifiableMap(deepForge(starlightMap));\n    }\n    \n    public synchronized MutableGem getGem(String rune) {\n        MutableGem gem = starlightMap.get(rune);\n        return gem != null ? new MutableGem(gem.getGlowX(), gem.getGlowY()) : null;\n    }\n    \n    public synchronized void setGem(String rune, int glowX, int glowY) {\n        if (!starlightMap.containsKey(rune)) {\n            throw new IllegalArgumentException(\"Rune not found: \" + rune);\n        }\n        starlightMap.get(rune).setGlowX(glowX);\n        starlightMap.get(rune).setGlowY(glowY);\n    }\n    \n    private static Map<String, MutableGem> deepForge(Map<String, MutableGem> original) {\n        Map<String, MutableGem> copy = new HashMap<>();\n        for (Map.Entry<String, MutableGem> entry : original.entrySet()) {\n            copy.put(entry.getKey(), new MutableGem(entry.getValue().getGlowX(), entry.getValue().getGlowY()));\n        }\n        return copy;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutableGem> initialMap = new HashMap<>();\n        initialMap.put(\"alpha\", new MutableGem(10, 20));\n        initialMap.put(\"beta\", new MutableGem(30, 40));\n        initialMap.put(\"gamma\", new MutableGem(50, 60));\n        \n        CelestialGriffinTracker tracker = new CelestialGriffinTracker(initialMap);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"alpha\", i * 10, i * 20);\n                MutableGem gem = tracker.getGem(\"alpha\");\n                System.out.println(\"Thread 1 - Alpha: \" + gem.getGlowX() + \", \" + gem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setGem(\"beta\", i * 5, i * 15);\n                Map<String, MutableGem> allGems = tracker.getStarlights();\n                MutableGem betaGem = allGems.get(\"beta\");\n                System.out.println(\"Thread 2 - Beta: \" + betaGem.getGlowX() + \", \" + betaGem.getGlowY());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final state:\");\n        Map<String, MutableGem> finalMap = tracker.getStarlights();\n        for (Map.Entry<String, MutableGem> entry : finalMap.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue().getGlowX() + \", \" + entry.getValue().getGlowY());\n        }\n    }\n}\n\nclass MutableGem {\n    private int glowX;\n    private int glowY;\n    \n    public MutableGem(int glowX, int glowY) {\n        this.glowX = glowX;\n        this.glowY = glowY;\n    }\n    \n    public int getGlowX() {\n        return glowX;\n    }\n    \n    public void setGlowX(int glowX) {\n        this.glowX = glowX;\n    }\n    \n    public int getGlowY() {\n        return glowY;\n    }\n    \n    public void setGlowY(int glowY) {\n        this.glowY = glowY;\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Driver loop that induces deadlock under typical conditions. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class named SummonChaosOrbs that simulates concurrent energy swaps between magical orbs to demonstrate the possibility of arcane stasis in multithreaded spellcasting applications. The program should create a fixed number of threads (e.g., 2) and a fixed number of Orb objects (e.g., 5). Each thread performs a large number of random exchanges (e.g., 10 iterations), selecting two random orbs and transferring a random mana shard using a method from a class called EtherealFlux.transferEnergy(Orb from, Orb to, ManaShard amount). This method is expected to lock both orbs before performing the exchange and may throw an InsufficientManaException, which should be caught and ignored. Each orb is initialized with a default value and must be thread-safe or synchronized as needed. Use a nested static class FluxThread that extends Thread and implements the transfer logic. Use Random to generate random indices for orbs and mana shard amounts. \nThe requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class SummonChaosOrbs {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ORBS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Orb[] orbs = new Orb[NUM_ORBS];\n    private static final Random random = new Random();\n\n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_ORBS; i++) {\n            orbs[i] = new Orb(100);\n        }\n\n        FluxThread[] threads = new FluxThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new FluxThread();\n            threads[i].start();\n        }\n\n        for (FluxThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n\n        System.out.println(\"Energy swaps completed.\");\n        for (int i = 0; i < NUM_ORBS; i++) {\n            System.out.println(\"Orb \" + i + \": \" + orbs[i].getEnergy());\n        }\n    }\n\n    static class FluxThread extends Thread {\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_ORBS);\n                int toIndex = random.nextInt(NUM_ORBS);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_ORBS);\n                }\n                \n                ManaShard amount = new ManaShard(random.nextInt(20) + 1);\n                \n                try {\n                    EtherealFlux.transferEnergy(orbs[fromIndex], orbs[toIndex], amount);\n                } catch (InsufficientManaException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Orb {\n    private int energy;\n    private final ReentrantLock lock = new ReentrantLock();\n\n    public Orb(int initialEnergy) {\n        this.energy = initialEnergy;\n    }\n\n    public void lock() {\n        lock.lock();\n    }\n\n    public void unlock() {\n        lock.unlock();\n    }\n\n    public int getEnergy() {\n        lock.lock();\n        try {\n            return energy;\n        } finally {\n            lock.unlock();\n        }\n    }\n\n    public void setEnergy(int energy) {\n        this.energy = energy;\n    }\n\n    public void addEnergy(int amount) {\n        this.energy += amount;\n    }\n\n    public void removeEnergy(int amount) throws InsufficientManaException {\n        if (this.energy < amount) {\n            throw new InsufficientManaException();\n        }\n        this.energy -= amount;\n    }\n}\n\nclass ManaShard {\n    private final int value;\n\n    public ManaShard(int value) {\n        this.value = value;\n    }\n\n    public int getValue() {\n        return value;\n    }\n}\n\nclass EtherealFlux {\n    public static void transferEnergy(Orb from, Orb to, ManaShard amount) throws InsufficientManaException {\n        Orb first = from.hashCode() < to.hashCode() ? from : to;\n        Orb second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                from.removeEnergy(amount.getValue());\n                to.addEnergy(amount.getValue());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientManaException extends Exception {\n    public InsufficientManaException() {\n        super();\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class SummonChaosOrbs {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ORBS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Orb[] orbs = new Orb[NUM_ORBS];\n    private static final Random random = new Random();\n\n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_ORBS; i++) {\n            orbs[i] = new Orb(100);\n        }\n\n        FluxThread[] threads = new FluxThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new FluxThread();\n            threads[i].start();\n        }\n\n        for (FluxThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n\n        for (int i = 0; i < NUM_ORBS; i++) {\n            System.out.println(\"Orb \" + i + \" final mana: \" + orbs[i].getMana());\n        }\n    }\n\n    static class FluxThread extends Thread {\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_ORBS);\n                int toIndex = random.nextInt(NUM_ORBS);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_ORBS);\n                }\n                \n                ManaShard shard = new ManaShard(random.nextInt(20) + 1);\n                \n                try {\n                    EtherealFlux.transferEnergy(orbs[fromIndex], orbs[toIndex], shard);\n                } catch (InsufficientManaException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Orb {\n    private int mana;\n    private final ReentrantLock lock = new ReentrantLock();\n\n    public Orb(int initialMana) {\n        this.mana = initialMana;\n    }\n\n    public void lock() {\n        lock.lock();\n    }\n\n    public void unlock() {\n        lock.unlock();\n    }\n\n    public int getMana() {\n        lock.lock();\n        try {\n            return mana;\n        } finally {\n            lock.unlock();\n        }\n    }\n\n    public void setMana(int mana) {\n        this.mana = mana;\n    }\n}\n\nclass ManaShard {\n    private final int amount;\n\n    public ManaShard(int amount) {\n        this.amount = amount;\n    }\n\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass EtherealFlux {\n    public static void transferEnergy(Orb from, Orb to, ManaShard amount) throws InsufficientManaException {\n        Orb first = from.hashCode() < to.hashCode() ? from : to;\n        Orb second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                if (from.getMana() < amount.getAmount()) {\n                    throw new InsufficientManaException();\n                }\n                from.setMana(from.getMana() - amount.getAmount());\n                to.setMana(to.getMana() + amount.getAmount());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientManaException extends Exception {\n    public InsufficientManaException() {\n        super();\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class SummonChaosOrbs {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ORBS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Orb[] orbs = new Orb[NUM_ORBS];\n    private static final Random random = new Random();\n\n    public static void main(String[] args) throws InterruptedException {\n        for (int i = 0; i < NUM_ORBS; i++) {\n            orbs[i] = new Orb(100);\n        }\n\n        FluxThread[] threads = new FluxThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new FluxThread();\n            threads[i].start();\n        }\n\n        for (FluxThread thread : threads) {\n            thread.join();\n        }\n\n        for (int i = 0; i < NUM_ORBS; i++) {\n            System.out.println(\"Orb \" + i + \": \" + orbs[i].getMana());\n        }\n    }\n\n    static class FluxThread extends Thread {\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_ORBS);\n                int toIndex = random.nextInt(NUM_ORBS);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_ORBS);\n                }\n                \n                int amount = random.nextInt(50) + 1;\n                ManaShard manaShard = new ManaShard(amount);\n                \n                try {\n                    EtherealFlux.transferEnergy(orbs[fromIndex], orbs[toIndex], manaShard);\n                } catch (InsufficientManaException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Orb {\n    private int mana;\n    private final ReentrantLock lock = new ReentrantLock();\n\n    public Orb(int initialMana) {\n        this.mana = initialMana;\n    }\n\n    public void lock() {\n        lock.lock();\n    }\n\n    public void unlock() {\n        lock.unlock();\n    }\n\n    public int getMana() {\n        lock.lock();\n        try {\n            return mana;\n        } finally {\n            lock.unlock();\n        }\n    }\n\n    public void setMana(int mana) {\n        this.mana = mana;\n    }\n\n    public void addMana(int amount) {\n        this.mana += amount;\n    }\n\n    public void removeMana(int amount) throws InsufficientManaException {\n        if (this.mana < amount) {\n            throw new InsufficientManaException();\n        }\n        this.mana -= amount;\n    }\n}\n\nclass ManaShard {\n    private final int amount;\n\n    public ManaShard(int amount) {\n        this.amount = amount;\n    }\n\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass EtherealFlux {\n    public static void transferEnergy(Orb from, Orb to, ManaShard amount) throws InsufficientManaException {\n        Orb first = from.hashCode() < to.hashCode() ? from : to;\n        Orb second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                from.removeMana(amount.getAmount());\n                to.addMana(amount.getAmount());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientManaException extends Exception {\n    public InsufficientManaException() {\n        super();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.Random;\n\npublic class DemonstrateDeadlock {\nprivate static final int NUM_THREADS = 2;\nprivate static final int NUM_ACCOUNTS = 2;\nprivate static final int NUM_ITERATIONS = 10;\n\npublic static void main(String[] args) {\nfinal Random rnd = new Random();\nfinal Account[] accounts = new Account[NUM_ACCOUNTS];\n\nfor (int i = 0; i < accounts.length; i++)\naccounts[i] = new Account();\n\nclass TransferThread extends Thread {\npublic void run() {\nfor (int i = 0; i < NUM_ITERATIONS; i++) {\nint fromAcct = rnd.nextInt(NUM_ACCOUNTS);\nint toAcct = rnd.nextInt(NUM_ACCOUNTS);\nif (fromAcct == toAcct)\ncontinue;\nDollarAmount amount = new DollarAmount(rnd.nextInt(1000));\ntry {\nDynamicOrderDeadlock.transferMoney(accounts[fromAcct], accounts[toAcct], amount);\n} catch (DynamicOrderDeadlock.InsufficientFundsException ignored) {\n}\n}\n}\n}\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nnew TransferThread().start();\n}\n}\n}\n\nclass Account {\nprivate volatile int balance;\n\npublic Account() {\nthis.balance = 1000;\n}\n\npublic synchronized int getBalance() {\nreturn balance;\n}\n\npublic synchronized void setBalance(int balance) {\nthis.balance = balance;\n}\n}\n\nclass DollarAmount {\nprivate final int value;\n\npublic DollarAmount(int value) {\nthis.value = value;\n}\n\npublic int getValue() {\nreturn value;\n}\n}\n\nclass DynamicOrderDeadlock {\npublic static void transferMoney(Account fromAcct, Account toAcct, DollarAmount amount)\nthrows InsufficientFundsException {\nAccount first = fromAcct;\nAccount second = toAcct;\nif (System.identityHashCode(first) > System.identityHashCode(second)) {\nfirst = toAcct;\nsecond = fromAcct;\n}\n\nsynchronized (first) {\nsynchronized (second) {\nif (fromAcct.getBalance() < amount.getValue())\nthrow new InsufficientFundsException();\nfromAcct.setBalance(fromAcct.getBalance() - amount.getValue());\ntoAcct.setBalance(toAcct.getBalance() + amount.getValue());\n}\n}\n}\n\npublic static class InsufficientFundsException extends Exception {}\n}",
        "max_depth": "30",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 24.26%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 36.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 45.37%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=222086,visited=174463,backtracked=396313,end=828\nsearch:             maxDepth=256,constraints=0\nchoice generators:  thread=221673 (signal=0,lock=6226,sharedRef=130830,threadApi=36046,reschedule=39597), data=0\nheap:               new=278137,released=264265,maxLive=559,gcCycles=396536\ninstructions:       55829008\nmax memory:         1020MB\nloaded code:        classes=99,methods=2006\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 24.37%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 35.86%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 45.28%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=180622,visited=141757,backtracked=322169,end=744\nsearch:             maxDepth=256,constraints=0\nchoice generators:  thread=180250 (signal=0,lock=4823,sharedRef=107151,threadApi=29576,reschedule=31798), data=0\nheap:               new=218784,released=214813,maxLive=559,gcCycles=322366\ninstructions:       86220710\nmax memory:         1019MB\nloaded code:        classes=99,methods=2004\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 24.85%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 35.50%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 45.22%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=218770,visited=170957,backtracked=389532,end=842\nsearch:             maxDepth=256,constraints=0\nchoice generators:  thread=218350 (signal=0,lock=5937,sharedRef=128286,threadApi=36704,reschedule=38899), data=0\nheap:               new=331339,released=289599,maxLive=576,gcCycles=389714\ninstructions:       55889193\nmax memory:         1020MB\nloaded code:        classes=103,methods=2038\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            54.22,
            54.56,
            53.8
        ],
        "llm_output": [
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class SummonChaosOrbs {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ORBS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Orb[] orbs = new Orb[NUM_ORBS];\n    private static final Random random = new Random();\n\n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_ORBS; i++) {\n            orbs[i] = new Orb(100);\n        }\n\n        FluxThread[] threads = new FluxThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new FluxThread();\n            threads[i].start();\n        }\n\n        for (FluxThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n\n        System.out.println(\"Energy swaps completed.\");\n        for (int i = 0; i < NUM_ORBS; i++) {\n            System.out.println(\"Orb \" + i + \": \" + orbs[i].getEnergy());\n        }\n    }\n\n    static class FluxThread extends Thread {\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_ORBS);\n                int toIndex = random.nextInt(NUM_ORBS);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_ORBS);\n                }\n                \n                ManaShard amount = new ManaShard(random.nextInt(20) + 1);\n                \n                try {\n                    EtherealFlux.transferEnergy(orbs[fromIndex], orbs[toIndex], amount);\n                } catch (InsufficientManaException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Orb {\n    private int energy;\n    private final ReentrantLock lock = new ReentrantLock();\n\n    public Orb(int initialEnergy) {\n        this.energy = initialEnergy;\n    }\n\n    public void lock() {\n        lock.lock();\n    }\n\n    public void unlock() {\n        lock.unlock();\n    }\n\n    public int getEnergy() {\n        lock.lock();\n        try {\n            return energy;\n        } finally {\n            lock.unlock();\n        }\n    }\n\n    public void setEnergy(int energy) {\n        this.energy = energy;\n    }\n\n    public void addEnergy(int amount) {\n        this.energy += amount;\n    }\n\n    public void removeEnergy(int amount) throws InsufficientManaException {\n        if (this.energy < amount) {\n            throw new InsufficientManaException();\n        }\n        this.energy -= amount;\n    }\n}\n\nclass ManaShard {\n    private final int value;\n\n    public ManaShard(int value) {\n        this.value = value;\n    }\n\n    public int getValue() {\n        return value;\n    }\n}\n\nclass EtherealFlux {\n    public static void transferEnergy(Orb from, Orb to, ManaShard amount) throws InsufficientManaException {\n        Orb first = from.hashCode() < to.hashCode() ? from : to;\n        Orb second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                from.removeEnergy(amount.getValue());\n                to.addEnergy(amount.getValue());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientManaException extends Exception {\n    public InsufficientManaException() {\n        super();\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class SummonChaosOrbs {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ORBS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Orb[] orbs = new Orb[NUM_ORBS];\n    private static final Random random = new Random();\n\n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_ORBS; i++) {\n            orbs[i] = new Orb(100);\n        }\n\n        FluxThread[] threads = new FluxThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new FluxThread();\n            threads[i].start();\n        }\n\n        for (FluxThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n\n        for (int i = 0; i < NUM_ORBS; i++) {\n            System.out.println(\"Orb \" + i + \" final mana: \" + orbs[i].getMana());\n        }\n    }\n\n    static class FluxThread extends Thread {\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_ORBS);\n                int toIndex = random.nextInt(NUM_ORBS);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_ORBS);\n                }\n                \n                ManaShard shard = new ManaShard(random.nextInt(20) + 1);\n                \n                try {\n                    EtherealFlux.transferEnergy(orbs[fromIndex], orbs[toIndex], shard);\n                } catch (InsufficientManaException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Orb {\n    private int mana;\n    private final ReentrantLock lock = new ReentrantLock();\n\n    public Orb(int initialMana) {\n        this.mana = initialMana;\n    }\n\n    public void lock() {\n        lock.lock();\n    }\n\n    public void unlock() {\n        lock.unlock();\n    }\n\n    public int getMana() {\n        lock.lock();\n        try {\n            return mana;\n        } finally {\n            lock.unlock();\n        }\n    }\n\n    public void setMana(int mana) {\n        this.mana = mana;\n    }\n}\n\nclass ManaShard {\n    private final int amount;\n\n    public ManaShard(int amount) {\n        this.amount = amount;\n    }\n\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass EtherealFlux {\n    public static void transferEnergy(Orb from, Orb to, ManaShard amount) throws InsufficientManaException {\n        Orb first = from.hashCode() < to.hashCode() ? from : to;\n        Orb second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                if (from.getMana() < amount.getAmount()) {\n                    throw new InsufficientManaException();\n                }\n                from.setMana(from.getMana() - amount.getAmount());\n                to.setMana(to.getMana() + amount.getAmount());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientManaException extends Exception {\n    public InsufficientManaException() {\n        super();\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class SummonChaosOrbs {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ORBS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Orb[] orbs = new Orb[NUM_ORBS];\n    private static final Random random = new Random();\n\n    public static void main(String[] args) throws InterruptedException {\n        for (int i = 0; i < NUM_ORBS; i++) {\n            orbs[i] = new Orb(100);\n        }\n\n        FluxThread[] threads = new FluxThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new FluxThread();\n            threads[i].start();\n        }\n\n        for (FluxThread thread : threads) {\n            thread.join();\n        }\n\n        for (int i = 0; i < NUM_ORBS; i++) {\n            System.out.println(\"Orb \" + i + \": \" + orbs[i].getMana());\n        }\n    }\n\n    static class FluxThread extends Thread {\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_ORBS);\n                int toIndex = random.nextInt(NUM_ORBS);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_ORBS);\n                }\n                \n                int amount = random.nextInt(50) + 1;\n                ManaShard manaShard = new ManaShard(amount);\n                \n                try {\n                    EtherealFlux.transferEnergy(orbs[fromIndex], orbs[toIndex], manaShard);\n                } catch (InsufficientManaException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Orb {\n    private int mana;\n    private final ReentrantLock lock = new ReentrantLock();\n\n    public Orb(int initialMana) {\n        this.mana = initialMana;\n    }\n\n    public void lock() {\n        lock.lock();\n    }\n\n    public void unlock() {\n        lock.unlock();\n    }\n\n    public int getMana() {\n        lock.lock();\n        try {\n            return mana;\n        } finally {\n            lock.unlock();\n        }\n    }\n\n    public void setMana(int mana) {\n        this.mana = mana;\n    }\n\n    public void addMana(int amount) {\n        this.mana += amount;\n    }\n\n    public void removeMana(int amount) throws InsufficientManaException {\n        if (this.mana < amount) {\n            throw new InsufficientManaException();\n        }\n        this.mana -= amount;\n    }\n}\n\nclass ManaShard {\n    private final int amount;\n\n    public ManaShard(int amount) {\n        this.amount = amount;\n    }\n\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass EtherealFlux {\n    public static void transferEnergy(Orb from, Orb to, ManaShard amount) throws InsufficientManaException {\n        Orb first = from.hashCode() < to.hashCode() ? from : to;\n        Orb second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                from.removeMana(amount.getAmount());\n                to.addMana(amount.getAmount());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientManaException extends Exception {\n    public InsufficientManaException() {\n        super();\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Driver loop that induces deadlock under typical conditions. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class named ChronoCrystalBalancer that simulates concurrent time shard swaps between enchanted crystals to demonstrate the possibility of temporal deadlock in multithreaded spellcraft applications. The program should create a fixed number of threads (e.g., 2) and a fixed number of Crystal objects (e.g., 5). Each thread performs a large number of random resonance shifts (e.g., 10 iterations), selecting two random crystals and transferring a random chronoshard using a method from a class called TemporalFlux.shiftResonance(Crystal from, Crystal to, ChronoShard amount). This method is expected to lock both crystals before performing the shift and may throw an InsufficientChronoException, which should be caught and ignored. Each crystal is initialized with a default value and must be thread-safe or synchronized as needed. Use a nested static class ResonanceThread that extends Thread and implements the transfer logic. Use Random to generate random indices for crystals and chronoshard amounts.\nThe requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ChronoCrystalBalancer {\n    \n    private static final int NUM_THREADS = 2;\n    private static final int NUM_CRYSTALS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Crystal[] crystals = new Crystal[NUM_CRYSTALS];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_CRYSTALS; i++) {\n            crystals[i] = new Crystal(100);\n        }\n        \n        ResonanceThread[] threads = new ResonanceThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new ResonanceThread();\n            threads[i].start();\n        }\n        \n        for (ResonanceThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class ResonanceThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_CRYSTALS);\n                int toIndex = random.nextInt(NUM_CRYSTALS);\n                \n                while (fromIndex == toIndex) {\n                    toIndex = random.nextInt(NUM_CRYSTALS);\n                }\n                \n                Crystal from = crystals[fromIndex];\n                Crystal to = crystals[toIndex];\n                ChronoShard amount = new ChronoShard(random.nextInt(50) + 1);\n                \n                try {\n                    TemporalFlux.shiftResonance(from, to, amount);\n                } catch (InsufficientChronoException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Crystal {\n    private final ReentrantLock lock = new ReentrantLock();\n    private int chronoValue;\n    \n    public Crystal(int initialValue) {\n        this.chronoValue = initialValue;\n    }\n    \n    public void lock() {\n        lock.lock();\n    }\n    \n    public void unlock() {\n        lock.unlock();\n    }\n    \n    public int getChronoValue() {\n        return chronoValue;\n    }\n    \n    public void setChronoValue(int value) {\n        this.chronoValue = value;\n    }\n}\n\nclass ChronoShard {\n    private final int amount;\n    \n    public ChronoShard(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass TemporalFlux {\n    public static void shiftResonance(Crystal from, Crystal to, ChronoShard amount) throws InsufficientChronoException {\n        Crystal first = from.hashCode() < to.hashCode() ? from : to;\n        Crystal second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                if (from.getChronoValue() < amount.getAmount()) {\n                    throw new InsufficientChronoException();\n                }\n                from.setChronoValue(from.getChronoValue() - amount.getAmount());\n                to.setChronoValue(to.getChronoValue() + amount.getAmount());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientChronoException extends Exception {\n    public InsufficientChronoException() {\n        super();\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ChronoCrystalBalancer {\n    private static final int NUM_CRYSTALS = 5;\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Crystal[] crystals = new Crystal[NUM_CRYSTALS];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_CRYSTALS; i++) {\n            crystals[i] = new Crystal(100);\n        }\n        \n        ResonanceThread[] threads = new ResonanceThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new ResonanceThread();\n            threads[i].start();\n        }\n        \n        for (ResonanceThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class ResonanceThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_CRYSTALS);\n                int toIndex = random.nextInt(NUM_CRYSTALS);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_CRYSTALS);\n                }\n                \n                Crystal from = crystals[fromIndex];\n                Crystal to = crystals[toIndex];\n                ChronoShard amount = new ChronoShard(random.nextInt(50) + 1);\n                \n                try {\n                    TemporalFlux.shiftResonance(from, to, amount);\n                } catch (InsufficientChronoException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Crystal {\n    private final Lock lock = new ReentrantLock();\n    private int chronoValue;\n    \n    public Crystal(int initialValue) {\n        this.chronoValue = initialValue;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n    \n    public int getChronoValue() {\n        return chronoValue;\n    }\n    \n    public void setChronoValue(int value) {\n        this.chronoValue = value;\n    }\n}\n\nclass ChronoShard {\n    private final int amount;\n    \n    public ChronoShard(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass TemporalFlux {\n    public static void shiftResonance(Crystal from, Crystal to, ChronoShard amount) throws InsufficientChronoException {\n        Crystal first = from.hashCode() < to.hashCode() ? from : to;\n        Crystal second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.getLock().lock();\n        try {\n            second.getLock().lock();\n            try {\n                if (from.getChronoValue() < amount.getAmount()) {\n                    throw new InsufficientChronoException();\n                }\n                from.setChronoValue(from.getChronoValue() - amount.getAmount());\n                to.setChronoValue(to.getChronoValue() + amount.getAmount());\n            } finally {\n                second.getLock().unlock();\n            }\n        } finally {\n            first.getLock().unlock();\n        }\n    }\n}\n\nclass InsufficientChronoException extends Exception {\n    public InsufficientChronoException() {\n        super();\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ChronoCrystalBalancer {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_CRYSTALS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Crystal[] crystals = new Crystal[NUM_CRYSTALS];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_CRYSTALS; i++) {\n            crystals[i] = new Crystal(100);\n        }\n        \n        Thread[] threads = new Thread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new ResonanceThread();\n            threads[i].start();\n        }\n        \n        for (Thread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        System.out.println(\"Temporal balancing complete\");\n    }\n    \n    static class ResonanceThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_CRYSTALS);\n                int toIndex = random.nextInt(NUM_CRYSTALS);\n                \n                while (fromIndex == toIndex) {\n                    toIndex = random.nextInt(NUM_CRYSTALS);\n                }\n                \n                int amount = random.nextInt(50) + 1;\n                ChronoShard chronoShard = new ChronoShard(amount);\n                \n                try {\n                    TemporalFlux.shiftResonance(crystals[fromIndex], crystals[toIndex], chronoShard);\n                } catch (InsufficientChronoException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Crystal {\n    private int chronoValue;\n    private final ReentrantLock lock = new ReentrantLock();\n    \n    public Crystal(int initialValue) {\n        this.chronoValue = initialValue;\n    }\n    \n    public void lock() {\n        lock.lock();\n    }\n    \n    public void unlock() {\n        lock.unlock();\n    }\n    \n    public int getChronoValue() {\n        return chronoValue;\n    }\n    \n    public void setChronoValue(int value) {\n        this.chronoValue = value;\n    }\n}\n\nclass ChronoShard {\n    private final int amount;\n    \n    public ChronoShard(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass TemporalFlux {\n    public static void shiftResonance(Crystal from, Crystal to, ChronoShard amount) throws InsufficientChronoException {\n        Crystal first = from.hashCode() < to.hashCode() ? from : to;\n        Crystal second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                if (from.getChronoValue() < amount.getAmount()) {\n                    throw new InsufficientChronoException();\n                }\n                from.setChronoValue(from.getChronoValue() - amount.getAmount());\n                to.setChronoValue(to.getChronoValue() + amount.getAmount());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientChronoException extends Exception {\n    public InsufficientChronoException() {\n        super();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.Random;\n\npublic class DemonstrateDeadlock {\nprivate static final int NUM_THREADS = 2;\nprivate static final int NUM_ACCOUNTS = 2;\nprivate static final int NUM_ITERATIONS = 10;\n\npublic static void main(String[] args) {\nfinal Random rnd = new Random();\nfinal Account[] accounts = new Account[NUM_ACCOUNTS];\n\nfor (int i = 0; i < accounts.length; i++)\naccounts[i] = new Account();\n\nclass TransferThread extends Thread {\npublic void run() {\nfor (int i = 0; i < NUM_ITERATIONS; i++) {\nint fromAcct = rnd.nextInt(NUM_ACCOUNTS);\nint toAcct = rnd.nextInt(NUM_ACCOUNTS);\nif (fromAcct == toAcct)\ncontinue;\nDollarAmount amount = new DollarAmount(rnd.nextInt(1000));\ntry {\nDynamicOrderDeadlock.transferMoney(accounts[fromAcct], accounts[toAcct], amount);\n} catch (DynamicOrderDeadlock.InsufficientFundsException ignored) {\n}\n}\n}\n}\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nnew TransferThread().start();\n}\n}\n}\n\nclass Account {\nprivate volatile int balance;\n\npublic Account() {\nthis.balance = 1000;\n}\n\npublic synchronized int getBalance() {\nreturn balance;\n}\n\npublic synchronized void setBalance(int balance) {\nthis.balance = balance;\n}\n}\n\nclass DollarAmount {\nprivate final int value;\n\npublic DollarAmount(int value) {\nthis.value = value;\n}\n\npublic int getValue() {\nreturn value;\n}\n}\n\nclass DynamicOrderDeadlock {\npublic static void transferMoney(Account fromAcct, Account toAcct, DollarAmount amount)\nthrows InsufficientFundsException {\nAccount first = fromAcct;\nAccount second = toAcct;\nif (System.identityHashCode(first) > System.identityHashCode(second)) {\nfirst = toAcct;\nsecond = fromAcct;\n}\n\nsynchronized (first) {\nsynchronized (second) {\nif (fromAcct.getBalance() < amount.getValue())\nthrow new InsufficientFundsException();\nfromAcct.setBalance(fromAcct.getBalance() - amount.getValue());\ntoAcct.setBalance(toAcct.getBalance() + amount.getValue());\n}\n}\n}\n\npublic static class InsufficientFundsException extends Exception {}\n}",
        "max_depth": "30",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.41%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.15%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.30%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=229735,visited=212898,backtracked=442558,end=86\nsearch:             maxDepth=194,constraints=0\nchoice generators:  thread=229692 (signal=0,lock=4530,sharedRef=146838,threadApi=4738,reschedule=63320), data=0\nheap:               new=234610,released=138647,maxLive=563,gcCycles=442633\ninstructions:       34746807\nmax memory:         1020MB\nloaded code:        classes=99,methods=2003\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.40%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.15%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.31%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=230704,visited=213831,backtracked=444416,end=86\nsearch:             maxDepth=194,constraints=0\nchoice generators:  thread=230662 (signal=0,lock=4530,sharedRef=147503,threadApi=4738,reschedule=63599), data=0\nheap:               new=235154,released=139071,maxLive=563,gcCycles=444535\ninstructions:       34895058\nmax memory:         1021MB\nloaded code:        classes=99,methods=2002\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.32%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.22%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.30%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=237432,visited=220237,backtracked=457555,end=86\nsearch:             maxDepth=194,constraints=0\nchoice generators:  thread=237389 (signal=0,lock=4532,sharedRef=151935,threadApi=4742,reschedule=65595), data=0\nheap:               new=214127,released=116850,maxLive=560,gcCycles=457669\ninstructions:       35015920\nmax memory:         1021MB\nloaded code:        classes=99,methods=2003\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            54.68,
            54.26,
            55.4
        ],
        "llm_output": [
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ChronoCrystalBalancer {\n    \n    private static final int NUM_THREADS = 2;\n    private static final int NUM_CRYSTALS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Crystal[] crystals = new Crystal[NUM_CRYSTALS];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_CRYSTALS; i++) {\n            crystals[i] = new Crystal(100);\n        }\n        \n        ResonanceThread[] threads = new ResonanceThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new ResonanceThread();\n            threads[i].start();\n        }\n        \n        for (ResonanceThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class ResonanceThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_CRYSTALS);\n                int toIndex = random.nextInt(NUM_CRYSTALS);\n                \n                while (fromIndex == toIndex) {\n                    toIndex = random.nextInt(NUM_CRYSTALS);\n                }\n                \n                Crystal from = crystals[fromIndex];\n                Crystal to = crystals[toIndex];\n                ChronoShard amount = new ChronoShard(random.nextInt(50) + 1);\n                \n                try {\n                    TemporalFlux.shiftResonance(from, to, amount);\n                } catch (InsufficientChronoException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Crystal {\n    private final ReentrantLock lock = new ReentrantLock();\n    private int chronoValue;\n    \n    public Crystal(int initialValue) {\n        this.chronoValue = initialValue;\n    }\n    \n    public void lock() {\n        lock.lock();\n    }\n    \n    public void unlock() {\n        lock.unlock();\n    }\n    \n    public int getChronoValue() {\n        return chronoValue;\n    }\n    \n    public void setChronoValue(int value) {\n        this.chronoValue = value;\n    }\n}\n\nclass ChronoShard {\n    private final int amount;\n    \n    public ChronoShard(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass TemporalFlux {\n    public static void shiftResonance(Crystal from, Crystal to, ChronoShard amount) throws InsufficientChronoException {\n        Crystal first = from.hashCode() < to.hashCode() ? from : to;\n        Crystal second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                if (from.getChronoValue() < amount.getAmount()) {\n                    throw new InsufficientChronoException();\n                }\n                from.setChronoValue(from.getChronoValue() - amount.getAmount());\n                to.setChronoValue(to.getChronoValue() + amount.getAmount());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientChronoException extends Exception {\n    public InsufficientChronoException() {\n        super();\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ChronoCrystalBalancer {\n    private static final int NUM_CRYSTALS = 5;\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Crystal[] crystals = new Crystal[NUM_CRYSTALS];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_CRYSTALS; i++) {\n            crystals[i] = new Crystal(100);\n        }\n        \n        ResonanceThread[] threads = new ResonanceThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new ResonanceThread();\n            threads[i].start();\n        }\n        \n        for (ResonanceThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class ResonanceThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_CRYSTALS);\n                int toIndex = random.nextInt(NUM_CRYSTALS);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_CRYSTALS);\n                }\n                \n                Crystal from = crystals[fromIndex];\n                Crystal to = crystals[toIndex];\n                ChronoShard amount = new ChronoShard(random.nextInt(50) + 1);\n                \n                try {\n                    TemporalFlux.shiftResonance(from, to, amount);\n                } catch (InsufficientChronoException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Crystal {\n    private final Lock lock = new ReentrantLock();\n    private int chronoValue;\n    \n    public Crystal(int initialValue) {\n        this.chronoValue = initialValue;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n    \n    public int getChronoValue() {\n        return chronoValue;\n    }\n    \n    public void setChronoValue(int value) {\n        this.chronoValue = value;\n    }\n}\n\nclass ChronoShard {\n    private final int amount;\n    \n    public ChronoShard(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass TemporalFlux {\n    public static void shiftResonance(Crystal from, Crystal to, ChronoShard amount) throws InsufficientChronoException {\n        Crystal first = from.hashCode() < to.hashCode() ? from : to;\n        Crystal second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.getLock().lock();\n        try {\n            second.getLock().lock();\n            try {\n                if (from.getChronoValue() < amount.getAmount()) {\n                    throw new InsufficientChronoException();\n                }\n                from.setChronoValue(from.getChronoValue() - amount.getAmount());\n                to.setChronoValue(to.getChronoValue() + amount.getAmount());\n            } finally {\n                second.getLock().unlock();\n            }\n        } finally {\n            first.getLock().unlock();\n        }\n    }\n}\n\nclass InsufficientChronoException extends Exception {\n    public InsufficientChronoException() {\n        super();\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class ChronoCrystalBalancer {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_CRYSTALS = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Crystal[] crystals = new Crystal[NUM_CRYSTALS];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_CRYSTALS; i++) {\n            crystals[i] = new Crystal(100);\n        }\n        \n        Thread[] threads = new Thread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new ResonanceThread();\n            threads[i].start();\n        }\n        \n        for (Thread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        System.out.println(\"Temporal balancing complete\");\n    }\n    \n    static class ResonanceThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_CRYSTALS);\n                int toIndex = random.nextInt(NUM_CRYSTALS);\n                \n                while (fromIndex == toIndex) {\n                    toIndex = random.nextInt(NUM_CRYSTALS);\n                }\n                \n                int amount = random.nextInt(50) + 1;\n                ChronoShard chronoShard = new ChronoShard(amount);\n                \n                try {\n                    TemporalFlux.shiftResonance(crystals[fromIndex], crystals[toIndex], chronoShard);\n                } catch (InsufficientChronoException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Crystal {\n    private int chronoValue;\n    private final ReentrantLock lock = new ReentrantLock();\n    \n    public Crystal(int initialValue) {\n        this.chronoValue = initialValue;\n    }\n    \n    public void lock() {\n        lock.lock();\n    }\n    \n    public void unlock() {\n        lock.unlock();\n    }\n    \n    public int getChronoValue() {\n        return chronoValue;\n    }\n    \n    public void setChronoValue(int value) {\n        this.chronoValue = value;\n    }\n}\n\nclass ChronoShard {\n    private final int amount;\n    \n    public ChronoShard(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass TemporalFlux {\n    public static void shiftResonance(Crystal from, Crystal to, ChronoShard amount) throws InsufficientChronoException {\n        Crystal first = from.hashCode() < to.hashCode() ? from : to;\n        Crystal second = from.hashCode() < to.hashCode() ? to : from;\n        \n        first.lock();\n        try {\n            second.lock();\n            try {\n                if (from.getChronoValue() < amount.getAmount()) {\n                    throw new InsufficientChronoException();\n                }\n                from.setChronoValue(from.getChronoValue() - amount.getAmount());\n                to.setChronoValue(to.getChronoValue() + amount.getAmount());\n            } finally {\n                second.unlock();\n            }\n        } finally {\n            first.unlock();\n        }\n    }\n}\n\nclass InsufficientChronoException extends Exception {\n    public InsufficientChronoException() {\n        super();\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Driver loop that induces deadlock under typical conditions. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class named GoblinGoldShuffle that simulates concurrent gold nugget trades between mischievous goblins to demonstrate the possibility of chaotic deadlock in multithreaded hoarding applications. The program should create a fixed number of threads (e.g., 2) and a fixed number of GoblinPouch objects (e.g., 5). Each thread performs a large number of random swaps (e.g., 10 iterations), selecting two random pouches and transferring a random gold clump using a method from a class called SneakyTrade.transferGold(GoblinPouch from, GoblinPouch to, GoldClump amount). This method is expected to lock both pouches before performing the swap and may throw an InsufficientGoldException, which should be caught and ignored. Each pouch is initialized with a default value and must be thread-safe or synchronized as needed. Use a nested static class TradeThread that extends Thread and implements the swap logic. Use Random to generate random indices for pouches and gold amounts. \nThe requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class GoblinGoldShuffle {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_POUCHES = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final GoblinPouch[] pouches = new GoblinPouch[NUM_POUCHES];\n\n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_POUCHES; i++) {\n            pouches[i] = new GoblinPouch(100);\n        }\n\n        TradeThread[] threads = new TradeThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new TradeThread(i);\n            threads[i].start();\n        }\n\n        for (TradeThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n\n    static class TradeThread extends Thread {\n        private final Random random = new Random();\n        private final int threadId;\n\n        public TradeThread(int threadId) {\n            this.threadId = threadId;\n        }\n\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_POUCHES);\n                int toIndex = random.nextInt(NUM_POUCHES);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_POUCHES);\n                }\n                \n                GoldClump amount = new GoldClump(random.nextInt(50) + 1);\n                \n                try {\n                    SneakyTrade.transferGold(pouches[fromIndex], pouches[toIndex], amount);\n                } catch (InsufficientGoldException e) {\n                }\n            }\n        }\n    }\n}\n\nclass GoblinPouch {\n    private final ReentrantLock lock = new ReentrantLock();\n    private int gold;\n\n    public GoblinPouch(int initialGold) {\n        this.gold = initialGold;\n    }\n\n    public ReentrantLock getLock() {\n        return lock;\n    }\n\n    public int getGold() {\n        return gold;\n    }\n\n    public void setGold(int gold) {\n        this.gold = gold;\n    }\n}\n\nclass GoldClump {\n    private final int amount;\n\n    public GoldClump(int amount) {\n        this.amount = amount;\n    }\n\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass SneakyTrade {\n    public static void transferGold(GoblinPouch from, GoblinPouch to, GoldClump amount) throws InsufficientGoldException {\n        from.getLock().lock();\n        try {\n            to.getLock().lock();\n            try {\n                if (from.getGold() < amount.getAmount()) {\n                    throw new InsufficientGoldException();\n                }\n                from.setGold(from.getGold() - amount.getAmount());\n                to.setGold(to.getGold() + amount.getAmount());\n            } finally {\n                to.getLock().unlock();\n            }\n        } finally {\n            from.getLock().unlock();\n        }\n    }\n}\n\nclass InsufficientGoldException extends Exception {\n    public InsufficientGoldException() {\n        super();\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class GoblinGoldShuffle {\n    \n    private static final int NUM_THREADS = 2;\n    private static final int NUM_POUCHES = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final GoblinPouch[] pouches = new GoblinPouch[NUM_POUCHES];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_POUCHES; i++) {\n            pouches[i] = new GoblinPouch(100);\n        }\n        \n        Thread[] threads = new Thread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new TradeThread();\n            threads[i].start();\n        }\n        \n        for (Thread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class TradeThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_POUCHES);\n                int toIndex = random.nextInt(NUM_POUCHES);\n                \n                if (fromIndex != toIndex) {\n                    GoblinPouch from = pouches[fromIndex];\n                    GoblinPouch to = pouches[toIndex];\n                    GoldClump amount = new GoldClump(random.nextInt(20) + 1);\n                    \n                    try {\n                        SneakyTrade.transferGold(from, to, amount);\n                    } catch (InsufficientGoldException e) {\n                    }\n                }\n            }\n        }\n    }\n}\n\nclass GoblinPouch {\n    private final ReentrantLock lock = new ReentrantLock();\n    private int gold;\n    \n    public GoblinPouch(int initialGold) {\n        this.gold = initialGold;\n    }\n    \n    public void lock() {\n        lock.lock();\n    }\n    \n    public void unlock() {\n        lock.unlock();\n    }\n    \n    public int getGold() {\n        return gold;\n    }\n    \n    public void addGold(int amount) {\n        gold += amount;\n    }\n    \n    public void removeGold(int amount) throws InsufficientGoldException {\n        if (gold < amount) {\n            throw new InsufficientGoldException();\n        }\n        gold -= amount;\n    }\n}\n\nclass GoldClump {\n    private final int amount;\n    \n    public GoldClump(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass SneakyTrade {\n    public static void transferGold(GoblinPouch from, GoblinPouch to, GoldClump amount) throws InsufficientGoldException {\n        from.lock();\n        try {\n            to.lock();\n            try {\n                from.removeGold(amount.getAmount());\n                to.addGold(amount.getAmount());\n            } finally {\n                to.unlock();\n            }\n        } finally {\n            from.unlock();\n        }\n    }\n}\n\nclass InsufficientGoldException extends Exception {\n    public InsufficientGoldException() {\n        super();\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class GoblinGoldShuffle {\n    private static final int THREAD_COUNT = 2;\n    private static final int POUCH_COUNT = 5;\n    private static final int ITERATIONS = 10;\n    private static final GoblinPouch[] pouches = new GoblinPouch[POUCH_COUNT];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < POUCH_COUNT; i++) {\n            pouches[i] = new GoblinPouch(100);\n        }\n        \n        TradeThread[] threads = new TradeThread[THREAD_COUNT];\n        for (int i = 0; i < THREAD_COUNT; i++) {\n            threads[i] = new TradeThread();\n            threads[i].start();\n        }\n        \n        for (TradeThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class TradeThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < ITERATIONS; i++) {\n                int fromIndex = random.nextInt(POUCH_COUNT);\n                int toIndex = random.nextInt(POUCH_COUNT);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(POUCH_COUNT);\n                }\n                \n                GoblinPouch from = pouches[fromIndex];\n                GoblinPouch to = pouches[toIndex];\n                GoldClump amount = new GoldClump(random.nextInt(50) + 1);\n                \n                try {\n                    SneakyTrade.transferGold(from, to, amount);\n                } catch (InsufficientGoldException e) {\n                }\n            }\n        }\n    }\n}\n\nclass GoblinPouch {\n    private int gold;\n    private final Lock lock = new ReentrantLock();\n    \n    public GoblinPouch(int initialGold) {\n        this.gold = initialGold;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n    \n    public int getGold() {\n        return gold;\n    }\n    \n    public void addGold(int amount) {\n        gold += amount;\n    }\n    \n    public void removeGold(int amount) throws InsufficientGoldException {\n        if (gold < amount) {\n            throw new InsufficientGoldException();\n        }\n        gold -= amount;\n    }\n}\n\nclass GoldClump {\n    private final int amount;\n    \n    public GoldClump(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass SneakyTrade {\n    public static void transferGold(GoblinPouch from, GoblinPouch to, GoldClump amount) throws InsufficientGoldException {\n        from.getLock().lock();\n        try {\n            to.getLock().lock();\n            try {\n                from.removeGold(amount.getAmount());\n                to.addGold(amount.getAmount());\n            } finally {\n                to.getLock().unlock();\n            }\n        } finally {\n            from.getLock().unlock();\n        }\n    }\n}\n\nclass InsufficientGoldException extends Exception {\n    public InsufficientGoldException() {\n        super();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.Random;\n\npublic class DemonstrateDeadlock {\nprivate static final int NUM_THREADS = 2;\nprivate static final int NUM_ACCOUNTS = 2;\nprivate static final int NUM_ITERATIONS = 10;\n\npublic static void main(String[] args) {\nfinal Random rnd = new Random();\nfinal Account[] accounts = new Account[NUM_ACCOUNTS];\n\nfor (int i = 0; i < accounts.length; i++)\naccounts[i] = new Account();\n\nclass TransferThread extends Thread {\npublic void run() {\nfor (int i = 0; i < NUM_ITERATIONS; i++) {\nint fromAcct = rnd.nextInt(NUM_ACCOUNTS);\nint toAcct = rnd.nextInt(NUM_ACCOUNTS);\nif (fromAcct == toAcct)\ncontinue;\nDollarAmount amount = new DollarAmount(rnd.nextInt(1000));\ntry {\nDynamicOrderDeadlock.transferMoney(accounts[fromAcct], accounts[toAcct], amount);\n} catch (DynamicOrderDeadlock.InsufficientFundsException ignored) {\n}\n}\n}\n}\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nnew TransferThread().start();\n}\n}\n}\n\nclass Account {\nprivate volatile int balance;\n\npublic Account() {\nthis.balance = 1000;\n}\n\npublic synchronized int getBalance() {\nreturn balance;\n}\n\npublic synchronized void setBalance(int balance) {\nthis.balance = balance;\n}\n}\n\nclass DollarAmount {\nprivate final int value;\n\npublic DollarAmount(int value) {\nthis.value = value;\n}\n\npublic int getValue() {\nreturn value;\n}\n}\n\nclass DynamicOrderDeadlock {\npublic static void transferMoney(Account fromAcct, Account toAcct, DollarAmount amount)\nthrows InsufficientFundsException {\nAccount first = fromAcct;\nAccount second = toAcct;\nif (System.identityHashCode(first) > System.identityHashCode(second)) {\nfirst = toAcct;\nsecond = fromAcct;\n}\n\nsynchronized (first) {\nsynchronized (second) {\nif (fromAcct.getBalance() < amount.getValue())\nthrow new InsufficientFundsException();\nfromAcct.setBalance(fromAcct.getBalance() - amount.getValue());\ntoAcct.setBalance(toAcct.getBalance() + amount.getValue());\n}\n}\n}\n\npublic static class InsufficientFundsException extends Exception {}\n}",
        "max_depth": "30",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.37%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.19%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.28%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=230796,visited=213855,backtracked=444555,end=84\nsearch:             maxDepth=193,constraints=0\nchoice generators:  thread=230754 (signal=0,lock=4126,sharedRef=149070,threadApi=4783,reschedule=62312), data=0\nheap:               new=201464,released=113854,maxLive=563,gcCycles=444651\ninstructions:       32411169\nmax memory:         1020MB\nloaded code:        classes=99,methods=2002\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.33%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.22%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.29%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=234655,visited=217418,backtracked=451969,end=84\nsearch:             maxDepth=193,constraints=0\nchoice generators:  thread=234613 (signal=0,lock=4127,sharedRef=151601,threadApi=4784,reschedule=63382), data=0\nheap:               new=225534,released=137539,maxLive=560,gcCycles=452073\ninstructions:       32923585\nmax memory:         1020MB\nloaded code:        classes=99,methods=2004\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.30%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.23%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.32%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=238498,visited=221049,backtracked=459435,end=84\nsearch:             maxDepth=193,constraints=0\nchoice generators:  thread=238456 (signal=0,lock=4127,sharedRef=154195,threadApi=4784,reschedule=64472), data=0\nheap:               new=227614,released=139041,maxLive=563,gcCycles=459547\ninstructions:       33378524\nmax memory:         1020MB\nloaded code:        classes=99,methods=2003\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            55.98,
            52.85,
            52.43
        ],
        "llm_output": [
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class GoblinGoldShuffle {\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_POUCHES = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final GoblinPouch[] pouches = new GoblinPouch[NUM_POUCHES];\n\n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_POUCHES; i++) {\n            pouches[i] = new GoblinPouch(100);\n        }\n\n        TradeThread[] threads = new TradeThread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new TradeThread(i);\n            threads[i].start();\n        }\n\n        for (TradeThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n\n    static class TradeThread extends Thread {\n        private final Random random = new Random();\n        private final int threadId;\n\n        public TradeThread(int threadId) {\n            this.threadId = threadId;\n        }\n\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_POUCHES);\n                int toIndex = random.nextInt(NUM_POUCHES);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(NUM_POUCHES);\n                }\n                \n                GoldClump amount = new GoldClump(random.nextInt(50) + 1);\n                \n                try {\n                    SneakyTrade.transferGold(pouches[fromIndex], pouches[toIndex], amount);\n                } catch (InsufficientGoldException e) {\n                }\n            }\n        }\n    }\n}\n\nclass GoblinPouch {\n    private final ReentrantLock lock = new ReentrantLock();\n    private int gold;\n\n    public GoblinPouch(int initialGold) {\n        this.gold = initialGold;\n    }\n\n    public ReentrantLock getLock() {\n        return lock;\n    }\n\n    public int getGold() {\n        return gold;\n    }\n\n    public void setGold(int gold) {\n        this.gold = gold;\n    }\n}\n\nclass GoldClump {\n    private final int amount;\n\n    public GoldClump(int amount) {\n        this.amount = amount;\n    }\n\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass SneakyTrade {\n    public static void transferGold(GoblinPouch from, GoblinPouch to, GoldClump amount) throws InsufficientGoldException {\n        from.getLock().lock();\n        try {\n            to.getLock().lock();\n            try {\n                if (from.getGold() < amount.getAmount()) {\n                    throw new InsufficientGoldException();\n                }\n                from.setGold(from.getGold() - amount.getAmount());\n                to.setGold(to.getGold() + amount.getAmount());\n            } finally {\n                to.getLock().unlock();\n            }\n        } finally {\n            from.getLock().unlock();\n        }\n    }\n}\n\nclass InsufficientGoldException extends Exception {\n    public InsufficientGoldException() {\n        super();\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class GoblinGoldShuffle {\n    \n    private static final int NUM_THREADS = 2;\n    private static final int NUM_POUCHES = 5;\n    private static final int NUM_ITERATIONS = 10;\n    private static final GoblinPouch[] pouches = new GoblinPouch[NUM_POUCHES];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_POUCHES; i++) {\n            pouches[i] = new GoblinPouch(100);\n        }\n        \n        Thread[] threads = new Thread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new TradeThread();\n            threads[i].start();\n        }\n        \n        for (Thread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class TradeThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_POUCHES);\n                int toIndex = random.nextInt(NUM_POUCHES);\n                \n                if (fromIndex != toIndex) {\n                    GoblinPouch from = pouches[fromIndex];\n                    GoblinPouch to = pouches[toIndex];\n                    GoldClump amount = new GoldClump(random.nextInt(20) + 1);\n                    \n                    try {\n                        SneakyTrade.transferGold(from, to, amount);\n                    } catch (InsufficientGoldException e) {\n                    }\n                }\n            }\n        }\n    }\n}\n\nclass GoblinPouch {\n    private final ReentrantLock lock = new ReentrantLock();\n    private int gold;\n    \n    public GoblinPouch(int initialGold) {\n        this.gold = initialGold;\n    }\n    \n    public void lock() {\n        lock.lock();\n    }\n    \n    public void unlock() {\n        lock.unlock();\n    }\n    \n    public int getGold() {\n        return gold;\n    }\n    \n    public void addGold(int amount) {\n        gold += amount;\n    }\n    \n    public void removeGold(int amount) throws InsufficientGoldException {\n        if (gold < amount) {\n            throw new InsufficientGoldException();\n        }\n        gold -= amount;\n    }\n}\n\nclass GoldClump {\n    private final int amount;\n    \n    public GoldClump(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass SneakyTrade {\n    public static void transferGold(GoblinPouch from, GoblinPouch to, GoldClump amount) throws InsufficientGoldException {\n        from.lock();\n        try {\n            to.lock();\n            try {\n                from.removeGold(amount.getAmount());\n                to.addGold(amount.getAmount());\n            } finally {\n                to.unlock();\n            }\n        } finally {\n            from.unlock();\n        }\n    }\n}\n\nclass InsufficientGoldException extends Exception {\n    public InsufficientGoldException() {\n        super();\n    }\n}\n```",
            "```java\nimport java.util.Random;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class GoblinGoldShuffle {\n    private static final int THREAD_COUNT = 2;\n    private static final int POUCH_COUNT = 5;\n    private static final int ITERATIONS = 10;\n    private static final GoblinPouch[] pouches = new GoblinPouch[POUCH_COUNT];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < POUCH_COUNT; i++) {\n            pouches[i] = new GoblinPouch(100);\n        }\n        \n        TradeThread[] threads = new TradeThread[THREAD_COUNT];\n        for (int i = 0; i < THREAD_COUNT; i++) {\n            threads[i] = new TradeThread();\n            threads[i].start();\n        }\n        \n        for (TradeThread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class TradeThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < ITERATIONS; i++) {\n                int fromIndex = random.nextInt(POUCH_COUNT);\n                int toIndex = random.nextInt(POUCH_COUNT);\n                while (toIndex == fromIndex) {\n                    toIndex = random.nextInt(POUCH_COUNT);\n                }\n                \n                GoblinPouch from = pouches[fromIndex];\n                GoblinPouch to = pouches[toIndex];\n                GoldClump amount = new GoldClump(random.nextInt(50) + 1);\n                \n                try {\n                    SneakyTrade.transferGold(from, to, amount);\n                } catch (InsufficientGoldException e) {\n                }\n            }\n        }\n    }\n}\n\nclass GoblinPouch {\n    private int gold;\n    private final Lock lock = new ReentrantLock();\n    \n    public GoblinPouch(int initialGold) {\n        this.gold = initialGold;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n    \n    public int getGold() {\n        return gold;\n    }\n    \n    public void addGold(int amount) {\n        gold += amount;\n    }\n    \n    public void removeGold(int amount) throws InsufficientGoldException {\n        if (gold < amount) {\n            throw new InsufficientGoldException();\n        }\n        gold -= amount;\n    }\n}\n\nclass GoldClump {\n    private final int amount;\n    \n    public GoldClump(int amount) {\n        this.amount = amount;\n    }\n    \n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass SneakyTrade {\n    public static void transferGold(GoblinPouch from, GoblinPouch to, GoldClump amount) throws InsufficientGoldException {\n        from.getLock().lock();\n        try {\n            to.getLock().lock();\n            try {\n                from.removeGold(amount.getAmount());\n                to.addGold(amount.getAmount());\n            } finally {\n                to.getLock().unlock();\n            }\n        } finally {\n            from.getLock().unlock();\n        }\n    }\n}\n\nclass InsufficientGoldException extends Exception {\n    public InsufficientGoldException() {\n        super();\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Barrier-based timer. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe CelestialHourglass class that implements the Runnable interface and is used to measure the flow of starlight between two cosmic events in a concurrent environment. The class should have three instance variables: a boolean activated, and two long values dawnTime and duskTime. When the run() method is called, it records the current chronon using System.nanoTime(). If this is the first call (i.e., activated is false), it sets activated to true and stores the time as dawnTime. On subsequent calls, it updates duskTime with the current chronon. Provide a reset() method that resets the hourglass by setting activated back to false. Also provide a getFlow() method that returns the difference between duskTime and dawnTime, representing the elapsed starlight in nanoseconds. All methods must be synchronized to ensure thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialHourglass implements Runnable {\n    private boolean activated;\n    private long dawnTime;\n    private long duskTime;\n    \n    public CelestialHourglass() {\n        this.activated = false;\n        this.dawnTime = 0;\n        this.duskTime = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!activated) {\n            activated = true;\n            dawnTime = currentTime;\n        } else {\n            duskTime = currentTime;\n        }\n    }\n    \n    public synchronized void reset() {\n        activated = false;\n    }\n    \n    public synchronized long getFlow() {\n        return duskTime - dawnTime;\n    }\n    \n    public static void main(String[] args) {\n        CelestialHourglass hourglass = new CelestialHourglass();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            hourglass.run();\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            hourglass.run();\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            hourglass.run();\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            hourglass.run();\n        });\n        \n        try {\n            Thread.sleep(300);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Flow: \" + hourglass.getFlow());\n        \n        hourglass.reset();\n        \n        executor.submit(hourglass);\n        executor.submit(hourglass);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final Flow: \" + hourglass.getFlow());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialHourglass implements Runnable {\n    private boolean activated = false;\n    private long dawnTime = 0;\n    private long duskTime = 0;\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!activated) {\n            activated = true;\n            dawnTime = currentTime;\n        } else {\n            duskTime = currentTime;\n        }\n    }\n    \n    public synchronized void reset() {\n        activated = false;\n    }\n    \n    public synchronized long getFlow() {\n        return duskTime - dawnTime;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        CelestialHourglass hourglass = new CelestialHourglass();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(hourglass);\n        Thread.sleep(100);\n        \n        executor.submit(hourglass);\n        Thread.sleep(100);\n        \n        executor.submit(hourglass);\n        Thread.sleep(100);\n        \n        executor.submit(hourglass);\n        Thread.sleep(100);\n        \n        System.out.println(\"Flow: \" + hourglass.getFlow());\n        \n        hourglass.reset();\n        \n        executor.submit(hourglass);\n        Thread.sleep(50);\n        \n        executor.submit(hourglass);\n        Thread.sleep(50);\n        \n        System.out.println(\"Flow after reset: \" + hourglass.getFlow());\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialHourglass implements Runnable {\n    private boolean activated;\n    private long dawnTime;\n    private long duskTime;\n    \n    public CelestialHourglass() {\n        this.activated = false;\n        this.dawnTime = 0;\n        this.duskTime = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentChronon = System.nanoTime();\n        if (!activated) {\n            activated = true;\n            dawnTime = currentChronon;\n        } else {\n            duskTime = currentChronon;\n        }\n    }\n    \n    public synchronized void reset() {\n        activated = false;\n    }\n    \n    public synchronized long getFlow() {\n        return duskTime - dawnTime;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        CelestialHourglass hourglass = new CelestialHourglass();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.execute(hourglass);\n        Thread.sleep(100);\n        \n        executor.execute(hourglass);\n        Thread.sleep(50);\n        \n        executor.execute(hourglass);\n        Thread.sleep(50);\n        \n        executor.execute(hourglass);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Starlight flow: \" + hourglass.getFlow() + \" nanoseconds\");\n        \n        hourglass.reset();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.execute(hourglass);\n        Thread.sleep(200);\n        executor2.execute(hourglass);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Starlight flow after reset: \" + hourglass.getFlow() + \" nanoseconds\");\n    }\n}"
        ],
        "graded_list": [
            false,
            true,
            true
        ],
        "ground_truth": "public class BarrierTimer implements Runnable {\nprivate boolean started;\nprivate long startTime, endTime;\n\npublic synchronized void run() {\nlong t = System.nanoTime();\nif (!started) {\nstarted = true;\nstartTime = t;\n} else {\nendTime = t;\n}\n}\n\npublic synchronized void clear() {\nstarted = false;\n}\n\npublic synchronized long getTime() {\nreturn endTime - startTime;\n}\n\npublic synchronized double getMillisTime() {\nreturn getTime() / 1_000_000.0;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal BarrierTimer timer = new BarrierTimer();\n\nThread starter = new Thread(() -> {\ntimer.run();\n});\n\nThread stopper = new Thread(() -> {\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\ntimer.run();\n});\n\nstarter.start();\nstopper.start();\n\nstarter.join();\nstopper.join();\n\nSystem.out.println(\"Elapsed time in nanoseconds: \" + timer.getTime());\nSystem.out.println(\"Elapsed time in milliseconds: \" + timer.getMillisTime());\n\ntimer.clear();\n}\n}",
        "max_depth": "166",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 58.33%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 58.34%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=179712,visited=141150,backtracked=319204,end=0\nsearch:             maxDepth=1660,constraints=80926\nchoice generators:  thread=134096 (signal=0,lock=3183,sharedRef=123868,threadApi=8,reschedule=3822), data=0\nheap:               new=52311,released=331594,maxLive=727,gcCycles=315129\ninstructions:       21902631\nmax memory:         1018MB\nloaded code:        classes=134,methods=2390\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 44.82%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.78%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 45.05%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 9.12%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 1.17%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=183559,visited=43194,backtracked=225094,end=0\nsearch:             maxDepth=1660,constraints=93889\nchoice generators:  thread=104919 (signal=0,lock=24225,sharedRef=33963,threadApi=2224,reschedule=41027), data=0\nheap:               new=539742,released=527346,maxLive=729,gcCycles=187274\ninstructions:       67657580\nmax memory:         1015MB\nloaded code:        classes=131,methods=2381\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nCelestialHourglass.main()\n====================================================== search started: 11/16/25 5:06 PM\nFlow: 0\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            71.82,
            65.13,
            66.11
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialHourglass implements Runnable {\n    private boolean activated;\n    private long dawnTime;\n    private long duskTime;\n    \n    public CelestialHourglass() {\n        this.activated = false;\n        this.dawnTime = 0;\n        this.duskTime = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!activated) {\n            activated = true;\n            dawnTime = currentTime;\n        } else {\n            duskTime = currentTime;\n        }\n    }\n    \n    public synchronized void reset() {\n        activated = false;\n    }\n    \n    public synchronized long getFlow() {\n        return duskTime - dawnTime;\n    }\n    \n    public static void main(String[] args) {\n        CelestialHourglass hourglass = new CelestialHourglass();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            hourglass.run();\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            hourglass.run();\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            hourglass.run();\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            hourglass.run();\n        });\n        \n        try {\n            Thread.sleep(300);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Flow: \" + hourglass.getFlow());\n        \n        hourglass.reset();\n        \n        executor.submit(hourglass);\n        executor.submit(hourglass);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final Flow: \" + hourglass.getFlow());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialHourglass implements Runnable {\n    private boolean activated = false;\n    private long dawnTime = 0;\n    private long duskTime = 0;\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!activated) {\n            activated = true;\n            dawnTime = currentTime;\n        } else {\n            duskTime = currentTime;\n        }\n    }\n    \n    public synchronized void reset() {\n        activated = false;\n    }\n    \n    public synchronized long getFlow() {\n        return duskTime - dawnTime;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        CelestialHourglass hourglass = new CelestialHourglass();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(hourglass);\n        Thread.sleep(100);\n        \n        executor.submit(hourglass);\n        Thread.sleep(100);\n        \n        executor.submit(hourglass);\n        Thread.sleep(100);\n        \n        executor.submit(hourglass);\n        Thread.sleep(100);\n        \n        System.out.println(\"Flow: \" + hourglass.getFlow());\n        \n        hourglass.reset();\n        \n        executor.submit(hourglass);\n        Thread.sleep(50);\n        \n        executor.submit(hourglass);\n        Thread.sleep(50);\n        \n        System.out.println(\"Flow after reset: \" + hourglass.getFlow());\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialHourglass implements Runnable {\n    private boolean activated;\n    private long dawnTime;\n    private long duskTime;\n    \n    public CelestialHourglass() {\n        this.activated = false;\n        this.dawnTime = 0;\n        this.duskTime = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentChronon = System.nanoTime();\n        if (!activated) {\n            activated = true;\n            dawnTime = currentChronon;\n        } else {\n            duskTime = currentChronon;\n        }\n    }\n    \n    public synchronized void reset() {\n        activated = false;\n    }\n    \n    public synchronized long getFlow() {\n        return duskTime - dawnTime;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        CelestialHourglass hourglass = new CelestialHourglass();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.execute(hourglass);\n        Thread.sleep(100);\n        \n        executor.execute(hourglass);\n        Thread.sleep(50);\n        \n        executor.execute(hourglass);\n        Thread.sleep(50);\n        \n        executor.execute(hourglass);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Starlight flow: \" + hourglass.getFlow() + \" nanoseconds\");\n        \n        hourglass.reset();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.execute(hourglass);\n        Thread.sleep(200);\n        executor2.execute(hourglass);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Starlight flow after reset: \" + hourglass.getFlow() + \" nanoseconds\");\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Barrier-based timer. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe DragonFlareTimer class that implements the Runnable interface and is used to measure the flare duration between two dragon breath events in a concurrent environment. The class should have three instance variables: a boolean ignited, and two long values flareStart and flareEnd. When the run() method is called, it records the current nano-blaze using System.nanoTime(). If this is the first call (i.e., ignited is false), it sets ignited to true and stores the time as flareStart. On subsequent calls, it updates flareEnd with the current nano-blaze. Provide a quench() method that resets the timer by setting ignited back to false. Also provide a getFlareDuration() method that returns the difference between flareEnd and flareStart, representing the elapsed dragon-fire in nanoseconds. All methods must be synchronized to ensure thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class DragonFlareTimer implements Runnable {\n    private boolean ignited;\n    private long flareStart;\n    private long flareEnd;\n\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!ignited) {\n            ignited = true;\n            flareStart = currentTime;\n        } else {\n            flareEnd = currentTime;\n        }\n    }\n\n    public synchronized void quench() {\n        ignited = false;\n    }\n\n    public synchronized long getFlareDuration() {\n        return flareEnd - flareStart;\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        DragonFlareTimer timer = new DragonFlareTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(timer);\n        Thread.sleep(100);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n        \n        timer.quench();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.submit(timer);\n        Thread.sleep(200);\n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"New Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class DragonFlareTimer implements Runnable {\n    private boolean ignited;\n    private long flareStart;\n    private long flareEnd;\n\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!ignited) {\n            ignited = true;\n            flareStart = currentTime;\n        } else {\n            flareEnd = currentTime;\n        }\n    }\n\n    public synchronized void quench() {\n        ignited = false;\n    }\n\n    public synchronized long getFlareDuration() {\n        return flareEnd - flareStart;\n    }\n\n    public static void main(String[] args) {\n        DragonFlareTimer timer = new DragonFlareTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                timer.run();\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                timer.run();\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n        timer.quench();\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class DragonFlareTimer implements Runnable {\n    private boolean ignited;\n    private long flareStart;\n    private long flareEnd;\n    \n    public DragonFlareTimer() {\n        this.ignited = false;\n        this.flareStart = 0;\n        this.flareEnd = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!ignited) {\n            ignited = true;\n            flareStart = currentTime;\n        } else {\n            flareEnd = currentTime;\n        }\n    }\n    \n    public synchronized void quench() {\n        ignited = false;\n    }\n    \n    public synchronized long getFlareDuration() {\n        return flareEnd - flareStart;\n    }\n    \n    public static void main(String[] args) {\n        DragonFlareTimer timer = new DragonFlareTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        \n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.submit(timer);\n        \n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        \n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n        \n        timer.quench();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        \n        executor2.submit(timer);\n        \n        try {\n            Thread.sleep(200);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        \n        try {\n            executor2.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"New Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class BarrierTimer implements Runnable {\nprivate boolean started;\nprivate long startTime, endTime;\n\npublic synchronized void run() {\nlong t = System.nanoTime();\nif (!started) {\nstarted = true;\nstartTime = t;\n} else {\nendTime = t;\n}\n}\n\npublic synchronized void clear() {\nstarted = false;\n}\n\npublic synchronized long getTime() {\nreturn endTime - startTime;\n}\n\npublic synchronized double getMillisTime() {\nreturn getTime() / 1_000_000.0;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal BarrierTimer timer = new BarrierTimer();\n\nThread starter = new Thread(() -> {\ntimer.run();\n});\n\nThread stopper = new Thread(() -> {\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\ntimer.run();\n});\n\nstarter.start();\nstopper.start();\n\nstarter.join();\nstopper.join();\n\nSystem.out.println(\"Elapsed time in nanoseconds: \" + timer.getTime());\nSystem.out.println(\"Elapsed time in milliseconds: \" + timer.getMillisTime());\n\ntimer.clear();\n}\n}",
        "max_depth": "166",
        "jpf_details": [
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.21%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.45%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.50%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 8.91%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 4.03%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=178615,visited=139930,backtracked=316887,end=0\nsearch:             maxDepth=1660,constraints=116212\nchoice generators:  thread=111579 (signal=0,lock=7691,sharedRef=94769,threadApi=590,reschedule=4395), data=0\nheap:               new=298641,released=116247,maxLive=760,gcCycles=283448\ninstructions:       15885438\nmax memory:         1019MB\nloaded code:        classes=134,methods=2390\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.13%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.26%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.27%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=149740,visited=135198,backtracked=283473,end=204\nsearch:             maxDepth=1660,constraints=59145\nchoice generators:  thread=98301 (signal=0,lock=18,sharedRef=78008,threadApi=2,reschedule=6625), data=0\nheap:               new=510767,released=271156,maxLive=743,gcCycles=277655\ninstructions:       35920751\nmax memory:         1018MB\nloaded code:        classes=140,methods=2442\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.17%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.45%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.50%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 8.89%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 4.02%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=179051,visited=140137,backtracked=317530,end=0\nsearch:             maxDepth=1660,constraints=116491\nchoice generators:  thread=111801 (signal=0,lock=7698,sharedRef=94942,threadApi=590,reschedule=4396), data=0\nheap:               new=299039,released=116394,maxLive=757,gcCycles=284051\ninstructions:       15952748\nmax memory:         1019MB\nloaded code:        classes=134,methods=2390\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            69.07,
            67.37,
            68.72
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class DragonFlareTimer implements Runnable {\n    private boolean ignited;\n    private long flareStart;\n    private long flareEnd;\n\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!ignited) {\n            ignited = true;\n            flareStart = currentTime;\n        } else {\n            flareEnd = currentTime;\n        }\n    }\n\n    public synchronized void quench() {\n        ignited = false;\n    }\n\n    public synchronized long getFlareDuration() {\n        return flareEnd - flareStart;\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        DragonFlareTimer timer = new DragonFlareTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(timer);\n        Thread.sleep(100);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n        \n        timer.quench();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.submit(timer);\n        Thread.sleep(200);\n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"New Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class DragonFlareTimer implements Runnable {\n    private boolean ignited;\n    private long flareStart;\n    private long flareEnd;\n\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!ignited) {\n            ignited = true;\n            flareStart = currentTime;\n        } else {\n            flareEnd = currentTime;\n        }\n    }\n\n    public synchronized void quench() {\n        ignited = false;\n    }\n\n    public synchronized long getFlareDuration() {\n        return flareEnd - flareStart;\n    }\n\n    public static void main(String[] args) {\n        DragonFlareTimer timer = new DragonFlareTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                timer.run();\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                timer.run();\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n        timer.quench();\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class DragonFlareTimer implements Runnable {\n    private boolean ignited;\n    private long flareStart;\n    private long flareEnd;\n    \n    public DragonFlareTimer() {\n        this.ignited = false;\n        this.flareStart = 0;\n        this.flareEnd = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!ignited) {\n            ignited = true;\n            flareStart = currentTime;\n        } else {\n            flareEnd = currentTime;\n        }\n    }\n    \n    public synchronized void quench() {\n        ignited = false;\n    }\n    \n    public synchronized long getFlareDuration() {\n        return flareEnd - flareStart;\n    }\n    \n    public static void main(String[] args) {\n        DragonFlareTimer timer = new DragonFlareTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        \n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.submit(timer);\n        \n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        \n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n        \n        timer.quench();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        \n        executor2.submit(timer);\n        \n        try {\n            Thread.sleep(200);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        \n        try {\n            executor2.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"New Flare Duration: \" + timer.getFlareDuration() + \" nanoseconds\");\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Barrier-based timer. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe MoonlightSandsTimer class that implements the Runnable interface and is used to measure the drift of moonlight sands between two enchanted events in a concurrent environment. The class should have three instance variables: a boolean flowing, and two long values sandStart and sandEnd. When the run() method is called, it records the current nano-grain using System.nanoTime(). If this is the first call (i.e., flowing is false), it sets flowing to true and stores the time as sandStart. On subsequent calls, it updates sandEnd with the current nano-grain. Provide a reset() method that restores the timer by setting flowing back to false. Also provide a getDrift() method that returns the difference between sandEnd and sandStart, representing the elapsed moonlight sands in nanoseconds. All methods must be synchronized to ensure thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MoonlightSandsTimer implements Runnable {\n    private boolean flowing;\n    private long sandStart;\n    private long sandEnd;\n\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!flowing) {\n            flowing = true;\n            sandStart = currentTime;\n        } else {\n            sandEnd = currentTime;\n        }\n    }\n\n    public synchronized void reset() {\n        flowing = false;\n    }\n\n    public synchronized long getDrift() {\n        return sandEnd - sandStart;\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        MoonlightSandsTimer timer = new MoonlightSandsTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        Thread.sleep(100);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Drift: \" + timer.getDrift() + \" nanoseconds\");\n        \n        timer.reset();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.submit(timer);\n        Thread.sleep(200);\n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"New drift: \" + timer.getDrift() + \" nanoseconds\");\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MoonlightSandsTimer implements Runnable {\n    private boolean flowing;\n    private long sandStart;\n    private long sandEnd;\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!flowing) {\n            flowing = true;\n            sandStart = currentTime;\n        } else {\n            sandEnd = currentTime;\n        }\n    }\n    \n    public synchronized void reset() {\n        flowing = false;\n    }\n    \n    public synchronized long getDrift() {\n        return sandEnd - sandStart;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        MoonlightSandsTimer timer = new MoonlightSandsTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        Thread.sleep(100);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Drift: \" + timer.getDrift() + \" nanoseconds\");\n        \n        timer.reset();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.submit(timer);\n        Thread.sleep(75);\n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"New drift: \" + timer.getDrift() + \" nanoseconds\");\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MoonlightSandsTimer implements Runnable {\n    private boolean flowing;\n    private long sandStart;\n    private long sandEnd;\n    \n    public MoonlightSandsTimer() {\n        this.flowing = false;\n        this.sandStart = 0;\n        this.sandEnd = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!flowing) {\n            flowing = true;\n            sandStart = currentTime;\n        } else {\n            sandEnd = currentTime;\n        }\n    }\n    \n    public synchronized void reset() {\n        flowing = false;\n    }\n    \n    public synchronized long getDrift() {\n        return sandEnd - sandStart;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        MoonlightSandsTimer timer = new MoonlightSandsTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        Thread.sleep(100);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Drift: \" + timer.getDrift() + \" nanoseconds\");\n        \n        timer.reset();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.submit(timer);\n        Thread.sleep(200);\n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"New Drift: \" + timer.getDrift() + \" nanoseconds\");\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class BarrierTimer implements Runnable {\nprivate boolean started;\nprivate long startTime, endTime;\n\npublic synchronized void run() {\nlong t = System.nanoTime();\nif (!started) {\nstarted = true;\nstartTime = t;\n} else {\nendTime = t;\n}\n}\n\npublic synchronized void clear() {\nstarted = false;\n}\n\npublic synchronized long getTime() {\nreturn endTime - startTime;\n}\n\npublic synchronized double getMillisTime() {\nreturn getTime() / 1_000_000.0;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal BarrierTimer timer = new BarrierTimer();\n\nThread starter = new Thread(() -> {\ntimer.run();\n});\n\nThread stopper = new Thread(() -> {\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\ntimer.run();\n});\n\nstarter.start();\nstopper.start();\n\nstarter.join();\nstopper.join();\n\nSystem.out.println(\"Elapsed time in nanoseconds: \" + timer.getTime());\nSystem.out.println(\"Elapsed time in milliseconds: \" + timer.getMillisTime());\n\ntimer.clear();\n}\n}",
        "max_depth": "166",
        "jpf_details": [
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.20%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.45%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.50%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 8.90%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 4.02%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=178892,visited=140234,backtracked=317470,end=0\nsearch:             maxDepth=1660,constraints=116378\nchoice generators:  thread=111778 (signal=0,lock=7694,sharedRef=94961,threadApi=590,reschedule=4397), data=0\nheap:               new=274703,released=91900,maxLive=760,gcCycles=283975\ninstructions:       15882545\nmax memory:         1019MB\nloaded code:        classes=134,methods=2390\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.47%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.50%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 9.02%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 4.10%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=175428,visited=137411,backtracked=311183,end=0\nsearch:             maxDepth=1660,constraints=114138\nchoice generators:  thread=109554 (signal=0,lock=7633,sharedRef=92926,threadApi=570,reschedule=4359), data=0\nheap:               new=269336,released=89550,maxLive=760,gcCycles=278459\ninstructions:       15682089\nmax memory:         1019MB\nloaded code:        classes=134,methods=2390\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 39.97%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.46%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.50%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 8.97%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 4.09%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=176179,visited=137642,backtracked=312162,end=0\nsearch:             maxDepth=1660,constraints=114652\nchoice generators:  thread=109908 (signal=0,lock=7647,sharedRef=93187,threadApi=574,reschedule=4366), data=0\nheap:               new=270116,released=90073,maxLive=760,gcCycles=279373\ninstructions:       15702419\nmax memory:         1019MB\nloaded code:        classes=134,methods=2390\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            69.07,
            68.7,
            66.11
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MoonlightSandsTimer implements Runnable {\n    private boolean flowing;\n    private long sandStart;\n    private long sandEnd;\n\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!flowing) {\n            flowing = true;\n            sandStart = currentTime;\n        } else {\n            sandEnd = currentTime;\n        }\n    }\n\n    public synchronized void reset() {\n        flowing = false;\n    }\n\n    public synchronized long getDrift() {\n        return sandEnd - sandStart;\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        MoonlightSandsTimer timer = new MoonlightSandsTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        Thread.sleep(100);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Drift: \" + timer.getDrift() + \" nanoseconds\");\n        \n        timer.reset();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.submit(timer);\n        Thread.sleep(200);\n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"New drift: \" + timer.getDrift() + \" nanoseconds\");\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MoonlightSandsTimer implements Runnable {\n    private boolean flowing;\n    private long sandStart;\n    private long sandEnd;\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!flowing) {\n            flowing = true;\n            sandStart = currentTime;\n        } else {\n            sandEnd = currentTime;\n        }\n    }\n    \n    public synchronized void reset() {\n        flowing = false;\n    }\n    \n    public synchronized long getDrift() {\n        return sandEnd - sandStart;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        MoonlightSandsTimer timer = new MoonlightSandsTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        Thread.sleep(100);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Drift: \" + timer.getDrift() + \" nanoseconds\");\n        \n        timer.reset();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.submit(timer);\n        Thread.sleep(75);\n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"New drift: \" + timer.getDrift() + \" nanoseconds\");\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MoonlightSandsTimer implements Runnable {\n    private boolean flowing;\n    private long sandStart;\n    private long sandEnd;\n    \n    public MoonlightSandsTimer() {\n        this.flowing = false;\n        this.sandStart = 0;\n        this.sandEnd = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!flowing) {\n            flowing = true;\n            sandStart = currentTime;\n        } else {\n            sandEnd = currentTime;\n        }\n    }\n    \n    public synchronized void reset() {\n        flowing = false;\n    }\n    \n    public synchronized long getDrift() {\n        return sandEnd - sandStart;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        MoonlightSandsTimer timer = new MoonlightSandsTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        Thread.sleep(100);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        Thread.sleep(50);\n        \n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Drift: \" + timer.getDrift() + \" nanoseconds\");\n        \n        timer.reset();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        executor2.submit(timer);\n        Thread.sleep(200);\n        executor2.submit(timer);\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"New Drift: \" + timer.getDrift() + \" nanoseconds\");\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Nonblocking counter using CAS. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe PixieDustCounter class that uses a custom EnchantedCAS implementation to provide magical increment functionality using the Compare-and-Swap (CAS) pattern. The PixieDustCounter should have an internal EnchantedCAS field and expose two methods: getDustLevel() which returns the current dust level, and sprinkle() which atomically increases the dust using a loop with CAS logic. The EnchantedCAS class must implement a compareAndSwap(int expected, int newValue) method that performs the swap only if the current dust level matches the expected one, returning the original value in both cases. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass EnchantedCAS {\n    private final AtomicInteger dust = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = dust.get();\n        if (original == expected) {\n            dust.set(newValue);\n        }\n        return original;\n    }\n}\n\nclass PixieDustCounter {\n    private final EnchantedCAS enchantedCAS = new EnchantedCAS();\n    \n    public int getDustLevel() {\n        int current;\n        int next;\n        do {\n            current = enchantedCAS.compareAndSwap(-1, -1);\n            next = current;\n        } while (enchantedCAS.compareAndSwap(current, next) != current);\n        return current;\n    }\n    \n    public void sprinkle() {\n        int current;\n        int next;\n        do {\n            current = enchantedCAS.compareAndSwap(-1, -1);\n            next = current + 1;\n        } while (enchantedCAS.compareAndSwap(current, next) != current);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        PixieDustCounter counter = new PixieDustCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.sprinkle();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final dust level: \" + counter.getDustLevel());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass EnchantedCAS {\n    private final AtomicInteger dust = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = dust.get();\n        if (original == expected) {\n            dust.set(newValue);\n        }\n        return original;\n    }\n}\n\nclass PixieDustCounter {\n    private final EnchantedCAS enchantedCAS = new EnchantedCAS();\n    \n    public int getDustLevel() {\n        int current;\n        int next;\n        do {\n            current = enchantedCAS.compareAndSwap(-1, -1);\n        } while (current == -1);\n        return current;\n    }\n    \n    public void sprinkle() {\n        int current;\n        int next;\n        do {\n            current = getDustLevel();\n            next = current + 1;\n        } while (enchantedCAS.compareAndSwap(current, next) != current);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        PixieDustCounter counter = new PixieDustCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.sprinkle();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final dust level: \" + counter.getDustLevel());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        PixieDustCounter counter = new PixieDustCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.sprinkle();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final dust level: \" + counter.getDustLevel());\n    }\n}\n\nclass PixieDustCounter {\n    private final EnchantedCAS enchantedCAS;\n    \n    public PixieDustCounter() {\n        this.enchantedCAS = new EnchantedCAS();\n    }\n    \n    public int getDustLevel() {\n        return enchantedCAS.getValue();\n    }\n    \n    public void sprinkle() {\n        while (true) {\n            int current = enchantedCAS.getValue();\n            int next = current + 1;\n            int witness = enchantedCAS.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\nclass EnchantedCAS {\n    private volatile int dustLevel = 0;\n    \n    public synchronized int compareAndSwap(int expected, int newValue) {\n        int oldValue = dustLevel;\n        if (oldValue == expected) {\n            dustLevel = newValue;\n        }\n        return oldValue;\n    }\n    \n    public int getValue() {\n        return dustLevel;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            false
        ],
        "ground_truth": "class SimulatedCAS {\nprivate int value;\n\npublic SimulatedCAS(int initialValue) {\nthis.value = initialValue;\n}\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized int compareAndSwap(int expectedValue, int newValue) {\nint oldValue = value;\nif (oldValue == expectedValue)\nvalue = newValue;\nreturn oldValue;\n}\n}\n\npublic class CasCounter {\nprivate final SimulatedCAS value;\n\npublic CasCounter() {\nthis.value = new SimulatedCAS(0);\n}\n\npublic int getValue() {\nreturn value.get();\n}\n\npublic int increment() {\nint v;\ndo {\nv = value.get();\n} while (v != value.compareAndSwap(v, v + 1));\nreturn v + 1;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nCasCounter counter = new CasCounter();\n\nfinal int NUM_THREADS = 2;\nfinal int INCREMENTS_PER_THREAD = 10;\n\nThread[] threads = new Thread[NUM_THREADS];\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nthreads[i] = new Thread(() -> {\nfor (int j = 0; j < INCREMENTS_PER_THREAD; j++) {\ncounter.increment();\n}\n});\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final counter value: \" + counter.getValue());\nSystem.out.println(\"Expected value: \" + (NUM_THREADS * INCREMENTS_PER_THREAD));\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.30%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.81%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.83%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=81736,visited=22262,backtracked=103832,end=22\nsearch:             maxDepth=200,constraints=52474\nchoice generators:  thread=35909 (signal=0,lock=4,sharedRef=23034,threadApi=2,reschedule=1911), data=0\nheap:               new=52197,released=77495,maxLive=723,gcCycles=103998\ninstructions:       168543379\nmax memory:         1010MB\nloaded code:        classes=138,methods=2412\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.26%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.85%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.90%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=80088,visited=20964,backtracked=100881,end=20\nsearch:             maxDepth=200,constraints=51832\nchoice generators:  thread=34825 (signal=0,lock=4,sharedRef=22272,threadApi=2,reschedule=1728), data=0\nheap:               new=47141,released=69656,maxLive=723,gcCycles=101052\ninstructions:       167464671\nmax memory:         1009MB\nloaded code:        classes=138,methods=2412\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.59%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.59%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field EnchantedCAS@1ca.dustLevel   pool-1...\"\n\n====================================================== statistics\nstates:             new=174599,visited=25559,backtracked=199958,end=0\nsearch:             maxDepth=200,constraints=123472\nchoice generators:  thread=66866 (signal=0,lock=420,sharedRef=40831,threadApi=2,reschedule=10), data=0\nheap:               new=1282,released=679,maxLive=726,gcCycles=199577\ninstructions:       6979370\nmax memory:         1016MB\nloaded code:        classes=136,methods=2395\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field EnchantedCAS@1ca.dustLevel   pool-1...\""
        ],
        "codebleu_score": [
            54.69,
            54.06,
            57.83
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass EnchantedCAS {\n    private final AtomicInteger dust = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = dust.get();\n        if (original == expected) {\n            dust.set(newValue);\n        }\n        return original;\n    }\n}\n\nclass PixieDustCounter {\n    private final EnchantedCAS enchantedCAS = new EnchantedCAS();\n    \n    public int getDustLevel() {\n        int current;\n        int next;\n        do {\n            current = enchantedCAS.compareAndSwap(-1, -1);\n            next = current;\n        } while (enchantedCAS.compareAndSwap(current, next) != current);\n        return current;\n    }\n    \n    public void sprinkle() {\n        int current;\n        int next;\n        do {\n            current = enchantedCAS.compareAndSwap(-1, -1);\n            next = current + 1;\n        } while (enchantedCAS.compareAndSwap(current, next) != current);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        PixieDustCounter counter = new PixieDustCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.sprinkle();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final dust level: \" + counter.getDustLevel());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass EnchantedCAS {\n    private final AtomicInteger dust = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = dust.get();\n        if (original == expected) {\n            dust.set(newValue);\n        }\n        return original;\n    }\n}\n\nclass PixieDustCounter {\n    private final EnchantedCAS enchantedCAS = new EnchantedCAS();\n    \n    public int getDustLevel() {\n        int current;\n        int next;\n        do {\n            current = enchantedCAS.compareAndSwap(-1, -1);\n        } while (current == -1);\n        return current;\n    }\n    \n    public void sprinkle() {\n        int current;\n        int next;\n        do {\n            current = getDustLevel();\n            next = current + 1;\n        } while (enchantedCAS.compareAndSwap(current, next) != current);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        PixieDustCounter counter = new PixieDustCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.sprinkle();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final dust level: \" + counter.getDustLevel());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        PixieDustCounter counter = new PixieDustCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.sprinkle();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final dust level: \" + counter.getDustLevel());\n    }\n}\n\nclass PixieDustCounter {\n    private final EnchantedCAS enchantedCAS;\n    \n    public PixieDustCounter() {\n        this.enchantedCAS = new EnchantedCAS();\n    }\n    \n    public int getDustLevel() {\n        return enchantedCAS.getValue();\n    }\n    \n    public void sprinkle() {\n        while (true) {\n            int current = enchantedCAS.getValue();\n            int next = current + 1;\n            int witness = enchantedCAS.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\nclass EnchantedCAS {\n    private volatile int dustLevel = 0;\n    \n    public synchronized int compareAndSwap(int expected, int newValue) {\n        int oldValue = dustLevel;\n        if (oldValue == expected) {\n            dustLevel = newValue;\n        }\n        return oldValue;\n    }\n    \n    public int getValue() {\n        return dustLevel;\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Nonblocking counter using CAS. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe DragonScaleCounter class that uses a custom MysticCAS implementation to provide arcane increment functionality using the Compare-and-Swap (CAS) pattern. The DragonScaleCounter should have an internal MysticCAS field and expose two methods: getScaleCount() which returns the current scale count, and growScale() which atomically adds a new scale using a loop with CAS logic. The MysticCAS class must implement a compareAndSwap(int expected, int newValue) method that performs the swap only if the current scale count matches the expected one, returning the original value in both cases. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass MysticCAS {\n    private final AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = value.get();\n        if (original == expected) {\n            value.set(newValue);\n        }\n        return original;\n    }\n    \n    public int getValue() {\n        return value.get();\n    }\n}\n\nclass DragonScaleCounter {\n    private final MysticCAS mysticCAS = new MysticCAS();\n    \n    public int getScaleCount() {\n        return mysticCAS.getValue();\n    }\n    \n    public void growScale() {\n        while (true) {\n            int current = getScaleCount();\n            int next = current + 1;\n            int original = mysticCAS.compareAndSwap(current, next);\n            if (original == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        DragonScaleCounter counter = new DragonScaleCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.growScale();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final scale count: \" + counter.getScaleCount());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass MysticCAS {\n    private AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        return value.compareAndExchange(expected, newValue);\n    }\n    \n    public int get() {\n        return value.get();\n    }\n}\n\nclass DragonScaleCounter {\n    private final MysticCAS mysticCAS = new MysticCAS();\n    \n    public int getScaleCount() {\n        return mysticCAS.get();\n    }\n    \n    public void growScale() {\n        while (true) {\n            int current = mysticCAS.get();\n            int next = current + 1;\n            int witness = mysticCAS.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        DragonScaleCounter counter = new DragonScaleCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.growScale();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final scale count: \" + counter.getScaleCount());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass MysticCAS {\n    private final AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int current = value.get();\n        if (current == expected) {\n            value.set(newValue);\n        }\n        return current;\n    }\n    \n    public int getValue() {\n        return value.get();\n    }\n}\n\nclass DragonScaleCounter {\n    private final MysticCAS mysticCAS = new MysticCAS();\n    \n    public int getScaleCount() {\n        return mysticCAS.getValue();\n    }\n    \n    public void growScale() {\n        while (true) {\n            int current = getScaleCount();\n            int next = current + 1;\n            int witness = mysticCAS.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class DragonScaleProgram {\n    public static void main(String[] args) throws InterruptedException {\n        DragonScaleCounter counter = new DragonScaleCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.growScale();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final scale count: \" + counter.getScaleCount());\n    }\n}"
        ],
        "graded_list": [
            true,
            false,
            true
        ],
        "ground_truth": "class SimulatedCAS {\nprivate int value;\n\npublic SimulatedCAS(int initialValue) {\nthis.value = initialValue;\n}\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized int compareAndSwap(int expectedValue, int newValue) {\nint oldValue = value;\nif (oldValue == expectedValue)\nvalue = newValue;\nreturn oldValue;\n}\n}\n\npublic class CasCounter {\nprivate final SimulatedCAS value;\n\npublic CasCounter() {\nthis.value = new SimulatedCAS(0);\n}\n\npublic int getValue() {\nreturn value.get();\n}\n\npublic int increment() {\nint v;\ndo {\nv = value.get();\n} while (v != value.compareAndSwap(v, v + 1));\nreturn v + 1;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nCasCounter counter = new CasCounter();\n\nfinal int NUM_THREADS = 2;\nfinal int INCREMENTS_PER_THREAD = 10;\n\nThread[] threads = new Thread[NUM_THREADS];\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nthreads[i] = new Thread(() -> {\nfor (int j = 0; j < INCREMENTS_PER_THREAD; j++) {\ncounter.increment();\n}\n});\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final counter value: \" + counter.getValue());\nSystem.out.println(\"Expected value: \" + (NUM_THREADS * INCREMENTS_PER_THREAD));\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.48%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.69%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.69%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=204087,visited=84265,backtracked=288250,end=101\nsearch:             maxDepth=200,constraints=122634\nchoice generators:  thread=97292 (signal=0,lock=4,sharedRef=68918,threadApi=2,reschedule=3092), data=0\nheap:               new=386838,released=498377,maxLive=743,gcCycles=284732\ninstructions:       22946254\nmax memory:         1019MB\nloaded code:        classes=142,methods=2443\n\n====================================================== search finished",
            "./temp_compile/Main.java:10: error: cannot find symbol\n        return value.compareAndExchange(expected, newValue);\n                    ^\n  symbol:   method compareAndExchange(int,int)\n  location: variable value of type AtomicInteger\n1 error",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.48%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.68%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.69%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=199717,visited=82659,backtracked=282261,end=100\nsearch:             maxDepth=200,constraints=119896\nchoice generators:  thread=95294 (signal=0,lock=4,sharedRef=67521,threadApi=2,reschedule=3043), data=0\nheap:               new=379325,released=489257,maxLive=743,gcCycles=278827\ninstructions:       22519753\nmax memory:         1018MB\nloaded code:        classes=142,methods=2443\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "syntax error",
            "no errors detected"
        ],
        "codebleu_score": [
            53.75,
            53.12,
            53.11
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass MysticCAS {\n    private final AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = value.get();\n        if (original == expected) {\n            value.set(newValue);\n        }\n        return original;\n    }\n    \n    public int getValue() {\n        return value.get();\n    }\n}\n\nclass DragonScaleCounter {\n    private final MysticCAS mysticCAS = new MysticCAS();\n    \n    public int getScaleCount() {\n        return mysticCAS.getValue();\n    }\n    \n    public void growScale() {\n        while (true) {\n            int current = getScaleCount();\n            int next = current + 1;\n            int original = mysticCAS.compareAndSwap(current, next);\n            if (original == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        DragonScaleCounter counter = new DragonScaleCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.growScale();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final scale count: \" + counter.getScaleCount());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass MysticCAS {\n    private AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        return value.compareAndExchange(expected, newValue);\n    }\n    \n    public int get() {\n        return value.get();\n    }\n}\n\nclass DragonScaleCounter {\n    private final MysticCAS mysticCAS = new MysticCAS();\n    \n    public int getScaleCount() {\n        return mysticCAS.get();\n    }\n    \n    public void growScale() {\n        while (true) {\n            int current = mysticCAS.get();\n            int next = current + 1;\n            int witness = mysticCAS.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        DragonScaleCounter counter = new DragonScaleCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.growScale();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final scale count: \" + counter.getScaleCount());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass MysticCAS {\n    private final AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int current = value.get();\n        if (current == expected) {\n            value.set(newValue);\n        }\n        return current;\n    }\n    \n    public int getValue() {\n        return value.get();\n    }\n}\n\nclass DragonScaleCounter {\n    private final MysticCAS mysticCAS = new MysticCAS();\n    \n    public int getScaleCount() {\n        return mysticCAS.getValue();\n    }\n    \n    public void growScale() {\n        while (true) {\n            int current = getScaleCount();\n            int next = current + 1;\n            int witness = mysticCAS.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class DragonScaleProgram {\n    public static void main(String[] args) throws InterruptedException {\n        DragonScaleCounter counter = new DragonScaleCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.growScale();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final scale count: \" + counter.getScaleCount());\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Nonblocking counter using CAS. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe StarlightShardCounter class that uses a custom QuantumCAS implementation to provide celestial increment functionality using the Compare-and-Swap (CAS) pattern. The StarlightShardCounter should have an internal QuantumCAS field and expose two methods: getShardLevel() which returns the current starlight shard level, and gatherShard() which atomically collects a shard using a loop with CAS logic. The QuantumCAS class must implement a compareAndSwap(int expected, int newValue) method that performs the swap only if the current shard level matches the expected one, returning the original value in both cases. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass QuantumCAS {\n    private final AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = value.get();\n        if (original == expected) {\n            value.compareAndSet(expected, newValue);\n        }\n        return original;\n    }\n    \n    public int get() {\n        return value.get();\n    }\n}\n\nclass StarlightShardCounter {\n    private final QuantumCAS quantumCAS = new QuantumCAS();\n    \n    public int getShardLevel() {\n        return quantumCAS.get();\n    }\n    \n    public void gatherShard() {\n        while (true) {\n            int current = getShardLevel();\n            int next = current + 1;\n            int original = quantumCAS.compareAndSwap(current, next);\n            if (original == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class ConcurrentShardProgram {\n    public static void main(String[] args) {\n        StarlightShardCounter counter = new StarlightShardCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.gatherShard();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final shard level: \" + counter.getShardLevel());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass QuantumCAS {\n    private final AtomicInteger value;\n    \n    public QuantumCAS() {\n        this.value = new AtomicInteger(0);\n    }\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = value.get();\n        if (original == expected) {\n            value.compareAndSet(expected, newValue);\n        }\n        return original;\n    }\n    \n    public int get() {\n        return value.get();\n    }\n}\n\nclass StarlightShardCounter {\n    private final QuantumCAS quantumCAS;\n    \n    public StarlightShardCounter() {\n        this.quantumCAS = new QuantumCAS();\n    }\n    \n    public int getShardLevel() {\n        return quantumCAS.get();\n    }\n    \n    public void gatherShard() {\n        while (true) {\n            int current = getShardLevel();\n            int next = current + 1;\n            int original = quantumCAS.compareAndSwap(current, next);\n            if (original == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        StarlightShardCounter counter = new StarlightShardCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.gatherShard();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final shard level: \" + counter.getShardLevel());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass QuantumCAS {\n    private final AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = value.get();\n        if (original == expected) {\n            value.compareAndSet(expected, newValue);\n        }\n        return original;\n    }\n    \n    public int get() {\n        return value.get();\n    }\n}\n\nclass StarlightShardCounter {\n    private final QuantumCAS quantumCAS = new QuantumCAS();\n    \n    public int getShardLevel() {\n        return quantumCAS.get();\n    }\n    \n    public void gatherShard() {\n        while (true) {\n            int current = getShardLevel();\n            int next = current + 1;\n            int original = quantumCAS.compareAndSwap(current, next);\n            if (original == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class StarlightShardProgram {\n    public static void main(String[] args) throws InterruptedException {\n        StarlightShardCounter counter = new StarlightShardCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.gatherShard();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final shard level: \" + counter.getShardLevel());\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "class SimulatedCAS {\nprivate int value;\n\npublic SimulatedCAS(int initialValue) {\nthis.value = initialValue;\n}\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized int compareAndSwap(int expectedValue, int newValue) {\nint oldValue = value;\nif (oldValue == expectedValue)\nvalue = newValue;\nreturn oldValue;\n}\n}\n\npublic class CasCounter {\nprivate final SimulatedCAS value;\n\npublic CasCounter() {\nthis.value = new SimulatedCAS(0);\n}\n\npublic int getValue() {\nreturn value.get();\n}\n\npublic int increment() {\nint v;\ndo {\nv = value.get();\n} while (v != value.compareAndSwap(v, v + 1));\nreturn v + 1;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nCasCounter counter = new CasCounter();\n\nfinal int NUM_THREADS = 2;\nfinal int INCREMENTS_PER_THREAD = 10;\n\nThread[] threads = new Thread[NUM_THREADS];\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nthreads[i] = new Thread(() -> {\nfor (int j = 0; j < INCREMENTS_PER_THREAD; j++) {\ncounter.increment();\n}\n});\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final counter value: \" + counter.getValue());\nSystem.out.println(\"Expected value: \" + (NUM_THREADS * INCREMENTS_PER_THREAD));\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nConcurrentShardProgram.main()\n====================================================== search started: 11/16/25 5:11 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/16/25 5:12 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nStarlightShardProgram.main()\n====================================================== search started: 11/16/25 5:12 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            53.44,
            57.2,
            53.75
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass QuantumCAS {\n    private final AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = value.get();\n        if (original == expected) {\n            value.compareAndSet(expected, newValue);\n        }\n        return original;\n    }\n    \n    public int get() {\n        return value.get();\n    }\n}\n\nclass StarlightShardCounter {\n    private final QuantumCAS quantumCAS = new QuantumCAS();\n    \n    public int getShardLevel() {\n        return quantumCAS.get();\n    }\n    \n    public void gatherShard() {\n        while (true) {\n            int current = getShardLevel();\n            int next = current + 1;\n            int original = quantumCAS.compareAndSwap(current, next);\n            if (original == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class ConcurrentShardProgram {\n    public static void main(String[] args) {\n        StarlightShardCounter counter = new StarlightShardCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.gatherShard();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final shard level: \" + counter.getShardLevel());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass QuantumCAS {\n    private final AtomicInteger value;\n    \n    public QuantumCAS() {\n        this.value = new AtomicInteger(0);\n    }\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = value.get();\n        if (original == expected) {\n            value.compareAndSet(expected, newValue);\n        }\n        return original;\n    }\n    \n    public int get() {\n        return value.get();\n    }\n}\n\nclass StarlightShardCounter {\n    private final QuantumCAS quantumCAS;\n    \n    public StarlightShardCounter() {\n        this.quantumCAS = new QuantumCAS();\n    }\n    \n    public int getShardLevel() {\n        return quantumCAS.get();\n    }\n    \n    public void gatherShard() {\n        while (true) {\n            int current = getShardLevel();\n            int next = current + 1;\n            int original = quantumCAS.compareAndSwap(current, next);\n            if (original == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        StarlightShardCounter counter = new StarlightShardCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.gatherShard();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final shard level: \" + counter.getShardLevel());\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\nclass QuantumCAS {\n    private final AtomicInteger value = new AtomicInteger(0);\n    \n    public int compareAndSwap(int expected, int newValue) {\n        int original = value.get();\n        if (original == expected) {\n            value.compareAndSet(expected, newValue);\n        }\n        return original;\n    }\n    \n    public int get() {\n        return value.get();\n    }\n}\n\nclass StarlightShardCounter {\n    private final QuantumCAS quantumCAS = new QuantumCAS();\n    \n    public int getShardLevel() {\n        return quantumCAS.get();\n    }\n    \n    public void gatherShard() {\n        while (true) {\n            int current = getShardLevel();\n            int next = current + 1;\n            int original = quantumCAS.compareAndSwap(current, next);\n            if (original == current) {\n                break;\n            }\n        }\n    }\n}\n\npublic class StarlightShardProgram {\n    public static void main(String[] args) throws InterruptedException {\n        StarlightShardCounter counter = new StarlightShardCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.gatherShard();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final shard level: \" + counter.getShardLevel());\n    }\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Using a factory method to prevent the this reference from escaping during construction. M1",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called MysticWatcher that securely attaches a magical observer to an ArcaneSource. The class should have a private constructor and a static factory method called summonInstance, which takes an ArcaneSource object as a parameter, creates an instance of MysticWatcher, registers a new ArcaneListener with the provided ArcaneSource, and returns the created MysticWatcher instance. The ArcaneListener should be implemented so that when its onMysticEvent method is called, it invokes a method named castSpell on the MysticWatcher instance. Also include empty definitions for the ArcaneSource, ArcaneListener, and MysticEvent interfaces so that the code compiles correctly. Ensure that the observer registration is done safely to prevent leaks or improper magical access. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticWatcher {\n    private final ArcaneSource source;\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    private MysticWatcher(ArcaneSource source) {\n        this.source = source;\n    }\n    \n    public static MysticWatcher summonInstance(ArcaneSource source) {\n        MysticWatcher watcher = new MysticWatcher(source);\n        ArcaneListener listener = new ArcaneListener() {\n            @Override\n            public void onMysticEvent(MysticEvent event) {\n                watcher.executor.execute(() -> watcher.castSpell());\n            }\n        };\n        source.registerListener(listener);\n        return watcher;\n    }\n    \n    private synchronized void castSpell() {\n        System.out.println(\"Casting spell on thread: \" + Thread.currentThread().getName());\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        ArcaneSource source = new ArcaneSourceImpl();\n        MysticWatcher watcher = MysticWatcher.summonInstance(source);\n        \n        for (int i = 0; i < 5; i++) {\n            source.triggerEvent(new MysticEventImpl());\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        watcher.shutdown();\n    }\n}\n\ninterface ArcaneSource {\n    void registerListener(ArcaneListener listener);\n    void triggerEvent(MysticEvent event);\n}\n\ninterface ArcaneListener {\n    void onMysticEvent(MysticEvent event);\n}\n\ninterface MysticEvent {\n}\n\nclass ArcaneSourceImpl implements ArcaneSource {\n    private volatile ArcaneListener listener;\n    \n    @Override\n    public synchronized void registerListener(ArcaneListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public void triggerEvent(MysticEvent event) {\n        ArcaneListener currentListener = listener;\n        if (currentListener != null) {\n            currentListener.onMysticEvent(event);\n        }\n    }\n}\n\nclass MysticEventImpl implements MysticEvent {\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticWatcher {\n    private final ArcaneSource source;\n    private final ArcaneListener listener;\n    private final ExecutorService executor;\n    \n    private MysticWatcher(ArcaneSource source) {\n        this.source = source;\n        this.executor = Executors.newSingleThreadExecutor();\n        this.listener = new ArcaneListener() {\n            @Override\n            public void onMysticEvent(MysticEvent event) {\n                executor.execute(() -> castSpell());\n            }\n        };\n    }\n    \n    public static MysticWatcher summonInstance(ArcaneSource source) {\n        MysticWatcher watcher = new MysticWatcher(source);\n        source.registerListener(watcher.listener);\n        return watcher;\n    }\n    \n    private void castSpell() {\n        System.out.println(\"Casting spell in thread: \" + Thread.currentThread().getName());\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n    }\n    \n    public static void main(String[] args) {\n        ArcaneSource source = new ArcaneSourceImpl();\n        MysticWatcher watcher = MysticWatcher.summonInstance(source);\n        \n        source.triggerEvent(new MysticEventImpl());\n        source.triggerEvent(new MysticEventImpl());\n        source.triggerEvent(new MysticEventImpl());\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        watcher.shutdown();\n    }\n}\n\ninterface ArcaneSource {\n    void registerListener(ArcaneListener listener);\n    void triggerEvent(MysticEvent event);\n}\n\ninterface ArcaneListener {\n    void onMysticEvent(MysticEvent event);\n}\n\ninterface MysticEvent {\n}\n\nclass ArcaneSourceImpl implements ArcaneSource {\n    private volatile ArcaneListener listener;\n    \n    @Override\n    public synchronized void registerListener(ArcaneListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public void triggerEvent(MysticEvent event) {\n        ArcaneListener currentListener = listener;\n        if (currentListener != null) {\n            currentListener.onMysticEvent(event);\n        }\n    }\n}\n\nclass MysticEventImpl implements MysticEvent {\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicReference;\n\ninterface ArcaneSource {\n    void registerListener(ArcaneListener listener);\n    void triggerEvent(MysticEvent event);\n}\n\ninterface ArcaneListener {\n    void onMysticEvent(MysticEvent event);\n}\n\ninterface MysticEvent {\n    String getMessage();\n}\n\nclass MysticWatcher {\n    private final AtomicReference<ArcaneListener> listenerRef = new AtomicReference<>();\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    private MysticWatcher() {}\n    \n    public static MysticWatcher summonInstance(ArcaneSource source) {\n        MysticWatcher watcher = new MysticWatcher();\n        ArcaneListener listener = new ArcaneListener() {\n            @Override\n            public void onMysticEvent(MysticEvent event) {\n                watcher.executor.execute(() -> watcher.castSpell());\n            }\n        };\n        watcher.listenerRef.set(listener);\n        source.registerListener(listener);\n        return watcher;\n    }\n    \n    private void castSpell() {\n        System.out.println(\"Casting spell from thread: \" + Thread.currentThread().getName());\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass SimpleArcaneSource implements ArcaneSource {\n    private volatile ArcaneListener listener;\n    \n    @Override\n    public synchronized void registerListener(ArcaneListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public void triggerEvent(MysticEvent event) {\n        ArcaneListener currentListener = listener;\n        if (currentListener != null) {\n            currentListener.onMysticEvent(event);\n        }\n    }\n}\n\nclass SimpleMysticEvent implements MysticEvent {\n    private final String message;\n    \n    public SimpleMysticEvent(String message) {\n        this.message = message;\n    }\n    \n    @Override\n    public String getMessage() {\n        return message;\n    }\n}\n\npublic class MagicalProgram {\n    public static void main(String[] args) {\n        SimpleArcaneSource source = new SimpleArcaneSource();\n        MysticWatcher watcher = MysticWatcher.summonInstance(source);\n        \n        source.triggerEvent(new SimpleMysticEvent(\"First event\"));\n        source.triggerEvent(new SimpleMysticEvent(\"Second event\"));\n        source.triggerEvent(new SimpleMysticEvent(\"Third event\"));\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        watcher.shutdown();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.CopyOnWriteArrayList;\n\npublic class SafeListener {\nprivate SafeListener(EventSource source) {\nsource.registerListener(new EventListener() {\n@Override\npublic void onEvent(Event e) {\ndoSomething();\n}\n});\n}\n\npublic static SafeListener newInstance(EventSource source) {\nreturn new SafeListener(source);\n}\n\nprivate synchronized void doSomething() {\nSystem.out.println(\"SafeListener is doing something.\");\n}\n\npublic static void main(String[] args) throws InterruptedException {\nEventSource source = new EventSource();\n\nSafeListener listener = SafeListener.newInstance(source);\n\nThread eventThread = new Thread(() -> {\nfor (int i = 0; i < 3; i++) {\nsource.fireEvent(new Event() {});\ntry {\nThread.sleep(100);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n\neventThread.start();\neventThread.join();\n}\n}\n\nclass EventSource {\nprivate final CopyOnWriteArrayList<EventListener> listeners = new CopyOnWriteArrayList<>();\n\npublic void registerListener(EventListener listener) {\nlisteners.add(listener);\n}\n\npublic void fireEvent(Event event) {\nfor (EventListener listener : listeners) {\nlistener.onEvent(event);\n}\n}\n}\n\ninterface EventListener {\nvoid onEvent(Event e);\n}\n\ninterface Event {}",
        "max_depth": "15",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 25.47%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 41.12%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=170123,visited=38093,backtracked=208075,end=36822\nsearch:             maxDepth=150,constraints=59298\nchoice generators:  thread=122586 (signal=0,lock=25031,sharedRef=11,threadApi=6,reschedule=36826), data=0\nheap:               new=568562,released=2317962,maxLive=721,gcCycles=208216\ninstructions:       69832870\nmax memory:         1018MB\nloaded code:        classes=139,methods=2410\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 34.68%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 34.56%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=71297,visited=35971,backtracked=107268,end=32840\nsearch:             maxDepth=150,constraints=1982\nchoice generators:  thread=70068 (signal=0,lock=44,sharedRef=28157,threadApi=5,reschedule=32874), data=0\nheap:               new=283741,released=1713404,maxLive=731,gcCycles=107268\ninstructions:       37828485\nmax memory:         1010MB\nloaded code:        classes=143,methods=2443\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 34.68%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 34.56%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=71297,visited=35971,backtracked=107268,end=32840\nsearch:             maxDepth=150,constraints=1982\nchoice generators:  thread=70068 (signal=0,lock=44,sharedRef=28157,threadApi=5,reschedule=32874), data=0\nheap:               new=283796,released=1746254,maxLive=744,gcCycles=107268\ninstructions:       37792884\nmax memory:         1011MB\nloaded code:        classes=145,methods=2460\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            67.96,
            64.77,
            65.87
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticWatcher {\n    private final ArcaneSource source;\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    private MysticWatcher(ArcaneSource source) {\n        this.source = source;\n    }\n    \n    public static MysticWatcher summonInstance(ArcaneSource source) {\n        MysticWatcher watcher = new MysticWatcher(source);\n        ArcaneListener listener = new ArcaneListener() {\n            @Override\n            public void onMysticEvent(MysticEvent event) {\n                watcher.executor.execute(() -> watcher.castSpell());\n            }\n        };\n        source.registerListener(listener);\n        return watcher;\n    }\n    \n    private synchronized void castSpell() {\n        System.out.println(\"Casting spell on thread: \" + Thread.currentThread().getName());\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        ArcaneSource source = new ArcaneSourceImpl();\n        MysticWatcher watcher = MysticWatcher.summonInstance(source);\n        \n        for (int i = 0; i < 5; i++) {\n            source.triggerEvent(new MysticEventImpl());\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        watcher.shutdown();\n    }\n}\n\ninterface ArcaneSource {\n    void registerListener(ArcaneListener listener);\n    void triggerEvent(MysticEvent event);\n}\n\ninterface ArcaneListener {\n    void onMysticEvent(MysticEvent event);\n}\n\ninterface MysticEvent {\n}\n\nclass ArcaneSourceImpl implements ArcaneSource {\n    private volatile ArcaneListener listener;\n    \n    @Override\n    public synchronized void registerListener(ArcaneListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public void triggerEvent(MysticEvent event) {\n        ArcaneListener currentListener = listener;\n        if (currentListener != null) {\n            currentListener.onMysticEvent(event);\n        }\n    }\n}\n\nclass MysticEventImpl implements MysticEvent {\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MysticWatcher {\n    private final ArcaneSource source;\n    private final ArcaneListener listener;\n    private final ExecutorService executor;\n    \n    private MysticWatcher(ArcaneSource source) {\n        this.source = source;\n        this.executor = Executors.newSingleThreadExecutor();\n        this.listener = new ArcaneListener() {\n            @Override\n            public void onMysticEvent(MysticEvent event) {\n                executor.execute(() -> castSpell());\n            }\n        };\n    }\n    \n    public static MysticWatcher summonInstance(ArcaneSource source) {\n        MysticWatcher watcher = new MysticWatcher(source);\n        source.registerListener(watcher.listener);\n        return watcher;\n    }\n    \n    private void castSpell() {\n        System.out.println(\"Casting spell in thread: \" + Thread.currentThread().getName());\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n    }\n    \n    public static void main(String[] args) {\n        ArcaneSource source = new ArcaneSourceImpl();\n        MysticWatcher watcher = MysticWatcher.summonInstance(source);\n        \n        source.triggerEvent(new MysticEventImpl());\n        source.triggerEvent(new MysticEventImpl());\n        source.triggerEvent(new MysticEventImpl());\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        watcher.shutdown();\n    }\n}\n\ninterface ArcaneSource {\n    void registerListener(ArcaneListener listener);\n    void triggerEvent(MysticEvent event);\n}\n\ninterface ArcaneListener {\n    void onMysticEvent(MysticEvent event);\n}\n\ninterface MysticEvent {\n}\n\nclass ArcaneSourceImpl implements ArcaneSource {\n    private volatile ArcaneListener listener;\n    \n    @Override\n    public synchronized void registerListener(ArcaneListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public void triggerEvent(MysticEvent event) {\n        ArcaneListener currentListener = listener;\n        if (currentListener != null) {\n            currentListener.onMysticEvent(event);\n        }\n    }\n}\n\nclass MysticEventImpl implements MysticEvent {\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicReference;\n\ninterface ArcaneSource {\n    void registerListener(ArcaneListener listener);\n    void triggerEvent(MysticEvent event);\n}\n\ninterface ArcaneListener {\n    void onMysticEvent(MysticEvent event);\n}\n\ninterface MysticEvent {\n    String getMessage();\n}\n\nclass MysticWatcher {\n    private final AtomicReference<ArcaneListener> listenerRef = new AtomicReference<>();\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    private MysticWatcher() {}\n    \n    public static MysticWatcher summonInstance(ArcaneSource source) {\n        MysticWatcher watcher = new MysticWatcher();\n        ArcaneListener listener = new ArcaneListener() {\n            @Override\n            public void onMysticEvent(MysticEvent event) {\n                watcher.executor.execute(() -> watcher.castSpell());\n            }\n        };\n        watcher.listenerRef.set(listener);\n        source.registerListener(listener);\n        return watcher;\n    }\n    \n    private void castSpell() {\n        System.out.println(\"Casting spell from thread: \" + Thread.currentThread().getName());\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass SimpleArcaneSource implements ArcaneSource {\n    private volatile ArcaneListener listener;\n    \n    @Override\n    public synchronized void registerListener(ArcaneListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public void triggerEvent(MysticEvent event) {\n        ArcaneListener currentListener = listener;\n        if (currentListener != null) {\n            currentListener.onMysticEvent(event);\n        }\n    }\n}\n\nclass SimpleMysticEvent implements MysticEvent {\n    private final String message;\n    \n    public SimpleMysticEvent(String message) {\n        this.message = message;\n    }\n    \n    @Override\n    public String getMessage() {\n        return message;\n    }\n}\n\npublic class MagicalProgram {\n    public static void main(String[] args) {\n        SimpleArcaneSource source = new SimpleArcaneSource();\n        MysticWatcher watcher = MysticWatcher.summonInstance(source);\n        \n        source.triggerEvent(new SimpleMysticEvent(\"First event\"));\n        source.triggerEvent(new SimpleMysticEvent(\"Second event\"));\n        source.triggerEvent(new SimpleMysticEvent(\"Third event\"));\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        watcher.shutdown();\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using a factory method to prevent the this reference from escaping during construction. M2",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called CelestialScribe that securely binds a starry observer to a CosmicSource. The class should have a private constructor and a static factory method called scribeInstance, which takes a CosmicSource object as a parameter, creates an instance of CelestialScribe, registers a new StarlightListener with the provided CosmicSource, and returns the created CelestialScribe instance. The StarlightListener should be implemented so that when its onCosmicEvent method is called, it invokes a method named recordTwinkle on the CelestialScribe instance. Also include empty definitions for the CosmicSource, StarlightListener, and CosmicEvent interfaces so that the code compiles correctly. Ensure that the observer registration is done safely to prevent leaks or improper astral access. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialScribe {\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    private volatile boolean recording = false;\n    \n    private CelestialScribe() {\n    }\n    \n    public static CelestialScribe scribeInstance(CosmicSource cosmicSource) {\n        CelestialScribe scribe = new CelestialScribe();\n        StarlightListener listener = new StarlightListener() {\n            @Override\n            public void onCosmicEvent(CosmicEvent event) {\n                scribe.recordTwinkle();\n            }\n        };\n        cosmicSource.registerListener(listener);\n        return scribe;\n    }\n    \n    public void recordTwinkle() {\n        executor.execute(() -> {\n            recording = true;\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            recording = false;\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        CosmicSource source = new CosmicSourceImpl();\n        CelestialScribe scribe = CelestialScribe.scribeInstance(source);\n        \n        for (int i = 0; i < 5; i++) {\n            source.emitEvent(new CosmicEventImpl());\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        scribe.shutdown();\n    }\n}\n\ninterface CosmicSource {\n    void registerListener(StarlightListener listener);\n    void emitEvent(CosmicEvent event);\n}\n\ninterface StarlightListener {\n    void onCosmicEvent(CosmicEvent event);\n}\n\ninterface CosmicEvent {\n}\n\nclass CosmicSourceImpl implements CosmicSource {\n    private StarlightListener listener;\n    \n    @Override\n    public synchronized void registerListener(StarlightListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public synchronized void emitEvent(CosmicEvent event) {\n        if (listener != null) {\n            listener.onCosmicEvent(event);\n        }\n    }\n}\n\nclass CosmicEventImpl implements CosmicEvent {\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialScribe {\n    private final CosmicSource cosmicSource;\n    private final ExecutorService executor;\n    private volatile boolean recording = false;\n    \n    private CelestialScribe(CosmicSource cosmicSource) {\n        this.cosmicSource = cosmicSource;\n        this.executor = Executors.newSingleThreadExecutor();\n    }\n    \n    public static CelestialScribe scribeInstance(CosmicSource cosmicSource) {\n        CelestialScribe scribe = new CelestialScribe(cosmicSource);\n        StarlightListener listener = new StarlightListener() {\n            @Override\n            public void onCosmicEvent(CosmicEvent event) {\n                scribe.recordTwinkle();\n            }\n        };\n        cosmicSource.registerListener(listener);\n        return scribe;\n    }\n    \n    private void recordTwinkle() {\n        executor.submit(() -> {\n            synchronized (this) {\n                recording = true;\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                recording = false;\n            }\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        CosmicSource source = new CosmicSource() {\n            private StarlightListener listener;\n            \n            @Override\n            public void registerListener(StarlightListener listener) {\n                this.listener = listener;\n            }\n            \n            @Override\n            public void emitEvent(CosmicEvent event) {\n                if (listener != null) {\n                    listener.onCosmicEvent(event);\n                }\n            }\n        };\n        \n        CelestialScribe scribe = CelestialScribe.scribeInstance(source);\n        \n        for (int i = 0; i < 3; i++) {\n            source.emitEvent(new CosmicEvent() {});\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        scribe.shutdown();\n    }\n}\n\ninterface CosmicSource {\n    void registerListener(StarlightListener listener);\n    void emitEvent(CosmicEvent event);\n}\n\ninterface StarlightListener {\n    void onCosmicEvent(CosmicEvent event);\n}\n\ninterface CosmicEvent {\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialScribe {\n    private final CosmicSource cosmicSource;\n    private final ExecutorService executor;\n    private volatile boolean isRecording = false;\n    \n    private CelestialScribe(CosmicSource cosmicSource) {\n        this.cosmicSource = cosmicSource;\n        this.executor = Executors.newSingleThreadExecutor();\n    }\n    \n    public static CelestialScribe scribeInstance(CosmicSource cosmicSource) {\n        CelestialScribe scribe = new CelestialScribe(cosmicSource);\n        StarlightListener listener = new StarlightListener() {\n            @Override\n            public void onCosmicEvent(CosmicEvent event) {\n                scribe.recordTwinkle();\n            }\n        };\n        cosmicSource.registerListener(listener);\n        return scribe;\n    }\n    \n    private synchronized void recordTwinkle() {\n        if (!isRecording) {\n            isRecording = true;\n            executor.submit(() -> {\n                try {\n                    Thread.sleep(100);\n                    System.out.println(\"Twinkle recorded by thread: \" + Thread.currentThread().getName());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    synchronized (CelestialScribe.this) {\n                        isRecording = false;\n                    }\n                }\n            });\n        }\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        CosmicSource source = new CosmicSourceImpl();\n        CelestialScribe scribe = CelestialScribe.scribeInstance(source);\n        \n        for (int i = 0; i < 5; i++) {\n            source.emitEvent(new CosmicEventImpl());\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        scribe.shutdown();\n    }\n}\n\ninterface CosmicSource {\n    void registerListener(StarlightListener listener);\n    void emitEvent(CosmicEvent event);\n}\n\ninterface StarlightListener {\n    void onCosmicEvent(CosmicEvent event);\n}\n\ninterface CosmicEvent {\n}\n\nclass CosmicSourceImpl implements CosmicSource {\n    private StarlightListener listener;\n    \n    @Override\n    public synchronized void registerListener(StarlightListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public synchronized void emitEvent(CosmicEvent event) {\n        if (listener != null) {\n            listener.onCosmicEvent(event);\n        }\n    }\n}\n\nclass CosmicEventImpl implements CosmicEvent {\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.concurrent.CopyOnWriteArrayList;\n\npublic class SafeListener {\nprivate SafeListener(EventSource source) {\nsource.registerListener(new EventListener() {\n@Override\npublic void onEvent(Event e) {\ndoSomething();\n}\n});\n}\n\npublic static SafeListener newInstance(EventSource source) {\nreturn new SafeListener(source);\n}\n\nprivate synchronized void doSomething() {\nSystem.out.println(\"SafeListener is doing something.\");\n}\n\npublic static void main(String[] args) throws InterruptedException {\nEventSource source = new EventSource();\n\nSafeListener listener = SafeListener.newInstance(source);\n\nThread eventThread = new Thread(() -> {\nfor (int i = 0; i < 3; i++) {\nsource.fireEvent(new Event() {});\ntry {\nThread.sleep(100);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n\neventThread.start();\neventThread.join();\n}\n}\n\nclass EventSource {\nprivate final CopyOnWriteArrayList<EventListener> listeners = new CopyOnWriteArrayList<>();\n\npublic void registerListener(EventListener listener) {\nlisteners.add(listener);\n}\n\npublic void fireEvent(Event event) {\nfor (EventListener listener : listeners) {\nlistener.onEvent(event);\n}\n}\n}\n\ninterface EventListener {\nvoid onEvent(Event e);\n}\n\ninterface Event {}",
        "max_depth": "15",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nCelestialScribe.main()\n====================================================== search started: 11/16/25 5:13 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nCelestialScribe.main()\n====================================================== search started: 11/16/25 5:13 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nCelestialScribe.main()\n====================================================== search started: 11/16/25 5:13 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            62.06,
            65.24,
            66.23
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialScribe {\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    private volatile boolean recording = false;\n    \n    private CelestialScribe() {\n    }\n    \n    public static CelestialScribe scribeInstance(CosmicSource cosmicSource) {\n        CelestialScribe scribe = new CelestialScribe();\n        StarlightListener listener = new StarlightListener() {\n            @Override\n            public void onCosmicEvent(CosmicEvent event) {\n                scribe.recordTwinkle();\n            }\n        };\n        cosmicSource.registerListener(listener);\n        return scribe;\n    }\n    \n    public void recordTwinkle() {\n        executor.execute(() -> {\n            recording = true;\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            recording = false;\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        CosmicSource source = new CosmicSourceImpl();\n        CelestialScribe scribe = CelestialScribe.scribeInstance(source);\n        \n        for (int i = 0; i < 5; i++) {\n            source.emitEvent(new CosmicEventImpl());\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        scribe.shutdown();\n    }\n}\n\ninterface CosmicSource {\n    void registerListener(StarlightListener listener);\n    void emitEvent(CosmicEvent event);\n}\n\ninterface StarlightListener {\n    void onCosmicEvent(CosmicEvent event);\n}\n\ninterface CosmicEvent {\n}\n\nclass CosmicSourceImpl implements CosmicSource {\n    private StarlightListener listener;\n    \n    @Override\n    public synchronized void registerListener(StarlightListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public synchronized void emitEvent(CosmicEvent event) {\n        if (listener != null) {\n            listener.onCosmicEvent(event);\n        }\n    }\n}\n\nclass CosmicEventImpl implements CosmicEvent {\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialScribe {\n    private final CosmicSource cosmicSource;\n    private final ExecutorService executor;\n    private volatile boolean recording = false;\n    \n    private CelestialScribe(CosmicSource cosmicSource) {\n        this.cosmicSource = cosmicSource;\n        this.executor = Executors.newSingleThreadExecutor();\n    }\n    \n    public static CelestialScribe scribeInstance(CosmicSource cosmicSource) {\n        CelestialScribe scribe = new CelestialScribe(cosmicSource);\n        StarlightListener listener = new StarlightListener() {\n            @Override\n            public void onCosmicEvent(CosmicEvent event) {\n                scribe.recordTwinkle();\n            }\n        };\n        cosmicSource.registerListener(listener);\n        return scribe;\n    }\n    \n    private void recordTwinkle() {\n        executor.submit(() -> {\n            synchronized (this) {\n                recording = true;\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                recording = false;\n            }\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        CosmicSource source = new CosmicSource() {\n            private StarlightListener listener;\n            \n            @Override\n            public void registerListener(StarlightListener listener) {\n                this.listener = listener;\n            }\n            \n            @Override\n            public void emitEvent(CosmicEvent event) {\n                if (listener != null) {\n                    listener.onCosmicEvent(event);\n                }\n            }\n        };\n        \n        CelestialScribe scribe = CelestialScribe.scribeInstance(source);\n        \n        for (int i = 0; i < 3; i++) {\n            source.emitEvent(new CosmicEvent() {});\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        scribe.shutdown();\n    }\n}\n\ninterface CosmicSource {\n    void registerListener(StarlightListener listener);\n    void emitEvent(CosmicEvent event);\n}\n\ninterface StarlightListener {\n    void onCosmicEvent(CosmicEvent event);\n}\n\ninterface CosmicEvent {\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CelestialScribe {\n    private final CosmicSource cosmicSource;\n    private final ExecutorService executor;\n    private volatile boolean isRecording = false;\n    \n    private CelestialScribe(CosmicSource cosmicSource) {\n        this.cosmicSource = cosmicSource;\n        this.executor = Executors.newSingleThreadExecutor();\n    }\n    \n    public static CelestialScribe scribeInstance(CosmicSource cosmicSource) {\n        CelestialScribe scribe = new CelestialScribe(cosmicSource);\n        StarlightListener listener = new StarlightListener() {\n            @Override\n            public void onCosmicEvent(CosmicEvent event) {\n                scribe.recordTwinkle();\n            }\n        };\n        cosmicSource.registerListener(listener);\n        return scribe;\n    }\n    \n    private synchronized void recordTwinkle() {\n        if (!isRecording) {\n            isRecording = true;\n            executor.submit(() -> {\n                try {\n                    Thread.sleep(100);\n                    System.out.println(\"Twinkle recorded by thread: \" + Thread.currentThread().getName());\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    synchronized (CelestialScribe.this) {\n                        isRecording = false;\n                    }\n                }\n            });\n        }\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        CosmicSource source = new CosmicSourceImpl();\n        CelestialScribe scribe = CelestialScribe.scribeInstance(source);\n        \n        for (int i = 0; i < 5; i++) {\n            source.emitEvent(new CosmicEventImpl());\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        scribe.shutdown();\n    }\n}\n\ninterface CosmicSource {\n    void registerListener(StarlightListener listener);\n    void emitEvent(CosmicEvent event);\n}\n\ninterface StarlightListener {\n    void onCosmicEvent(CosmicEvent event);\n}\n\ninterface CosmicEvent {\n}\n\nclass CosmicSourceImpl implements CosmicSource {\n    private StarlightListener listener;\n    \n    @Override\n    public synchronized void registerListener(StarlightListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public synchronized void emitEvent(CosmicEvent event) {\n        if (listener != null) {\n            listener.onCosmicEvent(event);\n        }\n    }\n}\n\nclass CosmicEventImpl implements CosmicEvent {\n}\n```"
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Using a factory method to prevent the this reference from escaping during construction. M3",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called GoblinEcho that securely attaches a mischievous listener to a TreasureSource. The class should have a private constructor and a static factory method called summonEcho, which takes a TreasureSource object as a parameter, creates an instance of GoblinEcho, registers a new WhisperListener with the provided TreasureSource, and returns the created GoblinEcho instance. The WhisperListener should be implemented so that when its onWhisper method is called, it invokes a method named performMischief on the GoblinEcho instance. Also include empty definitions for the TreasureSource, WhisperListener, and GoblinWhisper interfaces so that the code compiles correctly. Ensure that the listener registration is done safely to prevent leaks or improper goblin meddling. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations.",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class GoblinEcho {\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    private GoblinEcho() {\n    }\n    \n    public static GoblinEcho summonEcho(TreasureSource treasureSource) {\n        GoblinEcho goblinEcho = new GoblinEcho();\n        WhisperListener listener = new WhisperListener() {\n            @Override\n            public void onWhisper(GoblinWhisper whisper) {\n                goblinEcho.performMischief();\n            }\n        };\n        treasureSource.registerListener(listener);\n        return goblinEcho;\n    }\n    \n    private void performMischief() {\n        executor.submit(() -> {\n            System.out.println(\"Performing mischief in thread: \" + Thread.currentThread().getName());\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreasureSource treasureSource = new TreasureSourceImpl();\n        GoblinEcho goblinEcho = GoblinEcho.summonEcho(treasureSource);\n        \n        for (int i = 0; i < 5; i++) {\n            treasureSource.emitWhisper(new GoblinWhisperImpl());\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        goblinEcho.shutdown();\n    }\n}\n\ninterface TreasureSource {\n    void registerListener(WhisperListener listener);\n    void emitWhisper(GoblinWhisper whisper);\n}\n\ninterface WhisperListener {\n    void onWhisper(GoblinWhisper whisper);\n}\n\ninterface GoblinWhisper {\n}\n\nclass TreasureSourceImpl implements TreasureSource {\n    private volatile WhisperListener listener;\n    \n    @Override\n    public synchronized void registerListener(WhisperListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public void emitWhisper(GoblinWhisper whisper) {\n        WhisperListener currentListener = listener;\n        if (currentListener != null) {\n            currentListener.onWhisper(whisper);\n        }\n    }\n}\n\nclass GoblinWhisperImpl implements GoblinWhisper {\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class GoblinEcho {\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    private volatile boolean isActive = true;\n    \n    private GoblinEcho() {\n    }\n    \n    public static GoblinEcho summonEcho(TreasureSource treasureSource) {\n        GoblinEcho goblinEcho = new GoblinEcho();\n        WhisperListener listener = new WhisperListener() {\n            @Override\n            public void onWhisper(GoblinWhisper whisper) {\n                if (goblinEcho.isActive) {\n                    goblinEcho.performMischief();\n                }\n            }\n        };\n        treasureSource.registerListener(listener);\n        return goblinEcho;\n    }\n    \n    private void performMischief() {\n        executor.execute(() -> {\n            System.out.println(\"Performing mischief in thread: \" + Thread.currentThread().getName());\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n    }\n    \n    public void shutdown() {\n        isActive = false;\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreasureSource source = new TreasureSourceImpl();\n        GoblinEcho echo = GoblinEcho.summonEcho(source);\n        \n        for (int i = 0; i < 3; i++) {\n            source.triggerWhisper(new GoblinWhisperImpl(\"Whisper \" + i));\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        echo.shutdown();\n    }\n}\n\ninterface TreasureSource {\n    void registerListener(WhisperListener listener);\n    void triggerWhisper(GoblinWhisper whisper);\n}\n\ninterface WhisperListener {\n    void onWhisper(GoblinWhisper whisper);\n}\n\ninterface GoblinWhisper {\n    String getMessage();\n}\n\nclass TreasureSourceImpl implements TreasureSource {\n    private WhisperListener listener;\n    \n    @Override\n    public synchronized void registerListener(WhisperListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public synchronized void triggerWhisper(GoblinWhisper whisper) {\n        if (listener != null) {\n            listener.onWhisper(whisper);\n        }\n    }\n}\n\nclass GoblinWhisperImpl implements GoblinWhisper {\n    private final String message;\n    \n    public GoblinWhisperImpl(String message) {\n        this.message = message;\n    }\n    \n    @Override\n    public String getMessage() {\n        return message;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class GoblinEcho {\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    private volatile boolean active = true;\n    \n    private GoblinEcho() {}\n    \n    public static GoblinEcho summonEcho(TreasureSource treasureSource) {\n        GoblinEcho goblinEcho = new GoblinEcho();\n        WhisperListener listener = new WhisperListener() {\n            @Override\n            public void onWhisper(GoblinWhisper whisper) {\n                if (goblinEcho.active) {\n                    goblinEcho.executor.submit(() -> goblinEcho.performMischief());\n                }\n            }\n        };\n        treasureSource.addWhisperListener(listener);\n        return goblinEcho;\n    }\n    \n    private void performMischief() {\n        System.out.println(\"Performing mischief!\");\n    }\n    \n    public void shutdown() {\n        active = false;\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreasureSource source = new TreasureSourceImpl();\n        GoblinEcho echo = GoblinEcho.summonEcho(source);\n        \n        for (int i = 0; i < 5; i++) {\n            source.triggerWhisper(new GoblinWhisperImpl(\"Whisper \" + i));\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        echo.shutdown();\n    }\n}\n\ninterface TreasureSource {\n    void addWhisperListener(WhisperListener listener);\n    void triggerWhisper(GoblinWhisper whisper);\n}\n\ninterface WhisperListener {\n    void onWhisper(GoblinWhisper whisper);\n}\n\ninterface GoblinWhisper {\n    String getMessage();\n}\n\nclass TreasureSourceImpl implements TreasureSource {\n    private WhisperListener listener;\n    \n    @Override\n    public synchronized void addWhisperListener(WhisperListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public synchronized void triggerWhisper(GoblinWhisper whisper) {\n        if (listener != null) {\n            listener.onWhisper(whisper);\n        }\n    }\n}\n\nclass GoblinWhisperImpl implements GoblinWhisper {\n    private final String message;\n    \n    public GoblinWhisperImpl(String message) {\n        this.message = message;\n    }\n    \n    @Override\n    public String getMessage() {\n        return message;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.CopyOnWriteArrayList;\n\npublic class SafeListener {\nprivate SafeListener(EventSource source) {\nsource.registerListener(new EventListener() {\n@Override\npublic void onEvent(Event e) {\ndoSomething();\n}\n});\n}\n\npublic static SafeListener newInstance(EventSource source) {\nreturn new SafeListener(source);\n}\n\nprivate synchronized void doSomething() {\nSystem.out.println(\"SafeListener is doing something.\");\n}\n\npublic static void main(String[] args) throws InterruptedException {\nEventSource source = new EventSource();\n\nSafeListener listener = SafeListener.newInstance(source);\n\nThread eventThread = new Thread(() -> {\nfor (int i = 0; i < 3; i++) {\nsource.fireEvent(new Event() {});\ntry {\nThread.sleep(100);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n\neventThread.start();\neventThread.join();\n}\n}\n\nclass EventSource {\nprivate final CopyOnWriteArrayList<EventListener> listeners = new CopyOnWriteArrayList<>();\n\npublic void registerListener(EventListener listener) {\nlisteners.add(listener);\n}\n\npublic void fireEvent(Event event) {\nfor (EventListener listener : listeners) {\nlistener.onEvent(event);\n}\n}\n}\n\ninterface EventListener {\nvoid onEvent(Event e);\n}\n\ninterface Event {}",
        "max_depth": "15",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 24.21%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 42.07%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=173331,visited=34546,backtracked=207730,end=32809\nsearch:             maxDepth=150,constraints=64845\nchoice generators:  thread=120422 (signal=0,lock=26,sharedRef=394,threadApi=27719,reschedule=32813), data=0\nheap:               new=284112,released=2001438,maxLive=760,gcCycles=207877\ninstructions:       74157081\nmax memory:         1018MB\nloaded code:        classes=146,methods=2666\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 32.23%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 34.98%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=157821,visited=68581,backtracked=226363,end=67781\nsearch:             maxDepth=150,constraints=15184\nchoice generators:  thread=147121 (signal=0,lock=45,sharedRef=4117,threadApi=6082,reschedule=67814), data=0\nheap:               new=148096,released=3082057,maxLive=733,gcCycles=226402\ninstructions:       80184429\nmax memory:         1019MB\nloaded code:        classes=145,methods=2675\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.66%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 33.62%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=112493,visited=55351,backtracked=167694,end=54758\nsearch:             maxDepth=150,constraints=1729\nchoice generators:  thread=111340 (signal=0,lock=21,sharedRef=577,threadApi=6,reschedule=54772), data=0\nheap:               new=71208,released=3031569,maxLive=754,gcCycles=167844\ninstructions:       120841134\nmax memory:         1015MB\nloaded code:        classes=144,methods=2440\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            64.15,
            63.05,
            64.01
        ],
        "llm_output": [
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class GoblinEcho {\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    private GoblinEcho() {\n    }\n    \n    public static GoblinEcho summonEcho(TreasureSource treasureSource) {\n        GoblinEcho goblinEcho = new GoblinEcho();\n        WhisperListener listener = new WhisperListener() {\n            @Override\n            public void onWhisper(GoblinWhisper whisper) {\n                goblinEcho.performMischief();\n            }\n        };\n        treasureSource.registerListener(listener);\n        return goblinEcho;\n    }\n    \n    private void performMischief() {\n        executor.submit(() -> {\n            System.out.println(\"Performing mischief in thread: \" + Thread.currentThread().getName());\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreasureSource treasureSource = new TreasureSourceImpl();\n        GoblinEcho goblinEcho = GoblinEcho.summonEcho(treasureSource);\n        \n        for (int i = 0; i < 5; i++) {\n            treasureSource.emitWhisper(new GoblinWhisperImpl());\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        goblinEcho.shutdown();\n    }\n}\n\ninterface TreasureSource {\n    void registerListener(WhisperListener listener);\n    void emitWhisper(GoblinWhisper whisper);\n}\n\ninterface WhisperListener {\n    void onWhisper(GoblinWhisper whisper);\n}\n\ninterface GoblinWhisper {\n}\n\nclass TreasureSourceImpl implements TreasureSource {\n    private volatile WhisperListener listener;\n    \n    @Override\n    public synchronized void registerListener(WhisperListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public void emitWhisper(GoblinWhisper whisper) {\n        WhisperListener currentListener = listener;\n        if (currentListener != null) {\n            currentListener.onWhisper(whisper);\n        }\n    }\n}\n\nclass GoblinWhisperImpl implements GoblinWhisper {\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class GoblinEcho {\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    private volatile boolean isActive = true;\n    \n    private GoblinEcho() {\n    }\n    \n    public static GoblinEcho summonEcho(TreasureSource treasureSource) {\n        GoblinEcho goblinEcho = new GoblinEcho();\n        WhisperListener listener = new WhisperListener() {\n            @Override\n            public void onWhisper(GoblinWhisper whisper) {\n                if (goblinEcho.isActive) {\n                    goblinEcho.performMischief();\n                }\n            }\n        };\n        treasureSource.registerListener(listener);\n        return goblinEcho;\n    }\n    \n    private void performMischief() {\n        executor.execute(() -> {\n            System.out.println(\"Performing mischief in thread: \" + Thread.currentThread().getName());\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n    }\n    \n    public void shutdown() {\n        isActive = false;\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreasureSource source = new TreasureSourceImpl();\n        GoblinEcho echo = GoblinEcho.summonEcho(source);\n        \n        for (int i = 0; i < 3; i++) {\n            source.triggerWhisper(new GoblinWhisperImpl(\"Whisper \" + i));\n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        echo.shutdown();\n    }\n}\n\ninterface TreasureSource {\n    void registerListener(WhisperListener listener);\n    void triggerWhisper(GoblinWhisper whisper);\n}\n\ninterface WhisperListener {\n    void onWhisper(GoblinWhisper whisper);\n}\n\ninterface GoblinWhisper {\n    String getMessage();\n}\n\nclass TreasureSourceImpl implements TreasureSource {\n    private WhisperListener listener;\n    \n    @Override\n    public synchronized void registerListener(WhisperListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public synchronized void triggerWhisper(GoblinWhisper whisper) {\n        if (listener != null) {\n            listener.onWhisper(whisper);\n        }\n    }\n}\n\nclass GoblinWhisperImpl implements GoblinWhisper {\n    private final String message;\n    \n    public GoblinWhisperImpl(String message) {\n        this.message = message;\n    }\n    \n    @Override\n    public String getMessage() {\n        return message;\n    }\n}\n```",
            "```java\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class GoblinEcho {\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    private volatile boolean active = true;\n    \n    private GoblinEcho() {}\n    \n    public static GoblinEcho summonEcho(TreasureSource treasureSource) {\n        GoblinEcho goblinEcho = new GoblinEcho();\n        WhisperListener listener = new WhisperListener() {\n            @Override\n            public void onWhisper(GoblinWhisper whisper) {\n                if (goblinEcho.active) {\n                    goblinEcho.executor.submit(() -> goblinEcho.performMischief());\n                }\n            }\n        };\n        treasureSource.addWhisperListener(listener);\n        return goblinEcho;\n    }\n    \n    private void performMischief() {\n        System.out.println(\"Performing mischief!\");\n    }\n    \n    public void shutdown() {\n        active = false;\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreasureSource source = new TreasureSourceImpl();\n        GoblinEcho echo = GoblinEcho.summonEcho(source);\n        \n        for (int i = 0; i < 5; i++) {\n            source.triggerWhisper(new GoblinWhisperImpl(\"Whisper \" + i));\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        echo.shutdown();\n    }\n}\n\ninterface TreasureSource {\n    void addWhisperListener(WhisperListener listener);\n    void triggerWhisper(GoblinWhisper whisper);\n}\n\ninterface WhisperListener {\n    void onWhisper(GoblinWhisper whisper);\n}\n\ninterface GoblinWhisper {\n    String getMessage();\n}\n\nclass TreasureSourceImpl implements TreasureSource {\n    private WhisperListener listener;\n    \n    @Override\n    public synchronized void addWhisperListener(WhisperListener listener) {\n        this.listener = listener;\n    }\n    \n    @Override\n    public synchronized void triggerWhisper(GoblinWhisper whisper) {\n        if (listener != null) {\n            listener.onWhisper(whisper);\n        }\n    }\n}\n\nclass GoblinWhisperImpl implements GoblinWhisper {\n    private final String message;\n    \n    public GoblinWhisperImpl(String message) {\n        this.message = message;\n    }\n    \n    @Override\n    public String getMessage() {\n        return message;\n    }\n}\n```"
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Avoiding lock-ordering deadlock using try Lock. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that implements a deadlock avoidance mechanism for transferring money between two accounts. The program should use ReentrantLock to prevent deadlocks when acquiring locks on the source and destination accounts. Instead of blocking indefinitely, the implementation should utilize the tryLock() method with a timeout and random backoff strategy to attempt acquiring the locks. If both account locks are successfully acquired, the transfer should proceed only if the source account has sufficient funds; otherwise, an InsufficientFundsException is thrown. If the timeout period elapses before both locks can be acquired, the method should return false. The transfer method should accept parameters for the source account, destination account, amount to transfer, timeout duration, and time unit. Additionally, include nested classes for DollarAmount and Account, along with the custom exception InsufficientFundsException. Implement helper methods for calculating fixed and random delay components to be used before retrying the lock acquisition. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.Future;\nimport java.util.Random;\n\npublic class DeadlockAvoidanceTransfer {\n   \n   static class DollarAmount {\n       private final long cents;\n       \n       public DollarAmount(double dollars) {\n           this.cents = Math.round(dollars * 100);\n       }\n       \n       public DollarAmount(long cents) {\n           this.cents = cents;\n       }\n       \n       public long getCents() {\n           return cents;\n       }\n       \n       public double getDollars() {\n           return cents / 100.0;\n       }\n       \n       public DollarAmount add(DollarAmount other) {\n           return new DollarAmount(this.cents + other.cents);\n       }\n       \n       public DollarAmount subtract(DollarAmount other) {\n           return new DollarAmount(this.cents - other.cents);\n       }\n       \n       public boolean isGreaterThanOrEqual(DollarAmount other) {\n           return this.cents >= other.cents;\n       }\n       \n       public String toString() {\n           return String.format(\"$%.2f\", getDollars());\n       }\n   }\n   \n   static class Account {\n       private final int id;\n       private DollarAmount balance;\n       private final ReentrantLock lock;\n       \n       public Account(int id, DollarAmount initialBalance) {\n           this.id = id;\n           this.balance = initialBalance;\n           this.lock = new ReentrantLock();\n       }\n       \n       public int getId() {\n           return id;\n       }\n       \n       public DollarAmount getBalance() {\n           return balance;\n       }\n       \n       public void setBalance(DollarAmount balance) {\n           this.balance = balance;\n       }\n       \n       public ReentrantLock getLock() {\n           return lock;\n       }\n       \n       public String toString() {\n           return String.format(\"Account[id=%d, balance=%s]\", id, balance);\n       }\n   }\n   \n   static class InsufficientFundsException extends Exception {\n       public InsufficientFundsException(String message) {\n           super(message);\n       }\n   }\n   \n   private static final Random random = new Random();\n   \n   public static boolean transferMoney(Account source, Account destination, DollarAmount amount, \n                                     long timeout, TimeUnit unit) throws InsufficientFundsException {\n       long timeoutMillis = unit.toMillis(timeout);\n       long startTime = System.currentTimeMillis();\n       int maxRetries = 3;\n       int retryCount = 0;\n       \n       while (retryCount < maxRetries && (System.currentTimeMillis() - startTime) < timeoutMillis) {\n           Account firstLock = source.getId() < destination.getId() ? source : destination;\n           Account secondLock = source.getId() < destination.getId() ? destination : source;\n           \n           try {\n               boolean firstAcquired = firstLock.getLock().tryLock(50, TimeUnit.MILLISECONDS);\n               if (!firstAcquired) {\n                   retryCount++;\n                   Thread.sleep(calculateDelay());\n                   continue;\n               }\n               \n               try {\n                   boolean secondAcquired = secondLock.getLock().tryLock(50, TimeUnit.MILLISECONDS);\n                   if (!secondAcquired) {\n                       retryCount++;\n                       Thread.sleep(calculateDelay());\n                       continue;\n                   }\n                   \n                   try {\n                       if (!source.getBalance().isGreaterThanOrEqual(amount)) {\n                           throw new InsufficientFundsException(\n                               String.format(\"Insufficient funds in account %d\", source.getId()));\n                       }\n                       \n                       source.setBalance(source.getBalance().subtract(amount));\n                       destination.setBalance(destination.getBalance().add(amount));\n                       return true;\n                       \n                   } finally {\n                       secondLock.getLock().unlock();\n                   }\n               } finally {\n                   firstLock.getLock().unlock();\n               }\n           } catch (InterruptedException e) {\n               Thread.currentThread().interrupt();\n               return false;\n           }\n       }\n       \n       return false;\n   }\n   \n   private static long calculateDelay() {\n       return calculateFixedDelay() + calculateRandomDelay();\n   }\n   \n   private static long calculateFixedDelay() {\n       return 5;\n   }\n   \n   private static long calculateRandomDelay() {\n       return random.nextInt(10);\n   }\n   \n   public static void main(String[] args) {\n       Account account1 = new Account(1, new DollarAmount(1000.0));\n       Account account2 = new Account(2, new DollarAmount(500.0));\n       \n       ExecutorService executor = Executors.newFixedThreadPool(2);\n       \n       System.out.println(\"Initial: A1=\" + account1.getBalance() + \" A2=\" + account2.getBalance());\n       \n       Future<?> transfer1 = executor.submit(() -> {\n           try {\n               boolean success = transferMoney(account1, account2, new DollarAmount(200.0), 1, TimeUnit.SECONDS);\n               System.out.println(\"T1: \" + success);\n           } catch (InsufficientFundsException e) {\n               System.out.println(\"T1: FAILED\");\n           }\n       });\n       \n       Future<?> transfer2 = executor.submit(() -> {\n           try {\n               boolean success = transferMoney(account2, account1, new DollarAmount(100.0), 1, TimeUnit.SECONDS);\n               System.out.println(\"T2: \" + success);\n           } catch (InsufficientFundsException e) {\n               System.out.println(\"T2: FAILED\");\n           }\n       });\n       \n       try {\n           transfer1.get();\n           transfer2.get();\n       } catch (Exception e) {\n           System.out.println(\"Error\");\n       }\n       \n       System.out.println(\"Final: A1=\" + account1.getBalance() + \" A2=\" + account2.getBalance());\n       \n       executor.shutdown();\n   }\n}",
            "import java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class BankTransferSystem {\n    \n    private static final long FIXED_DELAY = 50L;\n    private static final long RANDOM_DELAY = 200L;\n    private static final Random random = new Random();\n    \n    public static void main(String[] args) {\n        Account account1 = new Account(\"ACC001\", new DollarAmount(1000));\n        Account account2 = new Account(\"ACC002\", new DollarAmount(500));\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                boolean result = transferMoney(account1, account2, new DollarAmount(300), 2, TimeUnit.SECONDS);\n                System.out.println(\"Transfer 1: \" + (result ? \"Success\" : \"Timeout\"));\n            } catch (InsufficientFundsException e) {\n                System.out.println(\"Transfer 1: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                boolean result = transferMoney(account2, account1, new DollarAmount(200), 2, TimeUnit.SECONDS);\n                System.out.println(\"Transfer 2: \" + (result ? \"Success\" : \"Timeout\"));\n            } catch (InsufficientFundsException e) {\n                System.out.println(\"Transfer 2: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final balance Account 1: \" + account1.getBalance().getAmount());\n        System.out.println(\"Final balance Account 2: \" + account2.getBalance().getAmount());\n    }\n    \n    public static boolean transferMoney(Account fromAccount, Account toAccount, \n                                       DollarAmount amount, long timeout, TimeUnit unit) \n                                       throws InsufficientFundsException {\n        long stopTime = System.nanoTime() + unit.toNanos(timeout);\n        \n        while (true) {\n            if (fromAccount.getLock().tryLock()) {\n                try {\n                    if (toAccount.getLock().tryLock()) {\n                        try {\n                            if (fromAccount.getBalance().getAmount() < amount.getAmount()) {\n                                throw new InsufficientFundsException(\"Insufficient funds in source account\");\n                            }\n                            fromAccount.debit(amount);\n                            toAccount.credit(amount);\n                            return true;\n                        } finally {\n                            toAccount.getLock().unlock();\n                        }\n                    }\n                } finally {\n                    fromAccount.getLock().unlock();\n                }\n            }\n            \n            if (System.nanoTime() >= stopTime) {\n                return false;\n            }\n            \n            try {\n                Thread.sleep(getFixedDelay() + getRandomDelay());\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            }\n        }\n    }\n    \n    private static long getFixedDelay() {\n        return FIXED_DELAY;\n    }\n    \n    private static long getRandomDelay() {\n        return (long) (random.nextDouble() * RANDOM_DELAY);\n    }\n    \n    static class DollarAmount {\n        private final long amount;\n        \n        public DollarAmount(long amount) {\n            this.amount = amount;\n        }\n        \n        public long getAmount() {\n            return amount;\n        }\n        \n        public DollarAmount add(DollarAmount other) {\n            return new DollarAmount(this.amount + other.amount);\n        }\n        \n        public DollarAmount subtract(DollarAmount other) {\n            return new DollarAmount(this.amount - other.amount);\n        }\n    }\n    \n    static class Account {\n        private final String id;\n        private DollarAmount balance;\n        private final ReentrantLock lock = new ReentrantLock();\n        \n        public Account(String id, DollarAmount initialBalance) {\n            this.id = id;\n            this.balance = initialBalance;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n        \n        public DollarAmount getBalance() {\n            return balance;\n        }\n        \n        public void debit(DollarAmount amount) {\n            balance = balance.subtract(amount);\n        }\n        \n        public void credit(DollarAmount amount) {\n            balance = balance.add(amount);\n        }\n        \n        public String getId() {\n            return id;\n        }\n    }\n    \n    static class InsufficientFundsException extends Exception {\n        public InsufficientFundsException(String message) {\n            super(message);\n        }\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class BankTransferSystem {\n    \n    private static final long FIXED_DELAY = 50L;\n    private static final long RANDOM_DELAY = 200L;\n    private static final Random random = new Random();\n    \n    public static void main(String[] args) {\n        Account account1 = new Account(1, new DollarAmount(1000));\n        Account account2 = new Account(2, new DollarAmount(500));\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                boolean result = transferMoney(account1, account2, new DollarAmount(300), 1000, TimeUnit.MILLISECONDS);\n                System.out.println(\"Transfer 1->2: \" + result);\n            } catch (InsufficientFundsException e) {\n                System.out.println(\"Transfer 1->2 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                boolean result = transferMoney(account2, account1, new DollarAmount(200), 1000, TimeUnit.MILLISECONDS);\n                System.out.println(\"Transfer 2->1: \" + result);\n            } catch (InsufficientFundsException e) {\n                System.out.println(\"Transfer 2->1 failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Account 1 balance: \" + account1.getBalance().getAmount());\n        System.out.println(\"Account 2 balance: \" + account2.getBalance().getAmount());\n    }\n    \n    public static boolean transferMoney(Account fromAccount, Account toAccount, DollarAmount amount, \n                                       long timeout, TimeUnit unit) throws InsufficientFundsException {\n        long stopTime = System.nanoTime() + unit.toNanos(timeout);\n        \n        while (true) {\n            if (fromAccount.getLock().tryLock()) {\n                try {\n                    if (toAccount.getLock().tryLock()) {\n                        try {\n                            if (fromAccount.getBalance().getAmount() < amount.getAmount()) {\n                                throw new InsufficientFundsException(\"Insufficient funds in source account\");\n                            }\n                            fromAccount.debit(amount);\n                            toAccount.credit(amount);\n                            return true;\n                        } finally {\n                            toAccount.getLock().unlock();\n                        }\n                    }\n                } finally {\n                    fromAccount.getLock().unlock();\n                }\n            }\n            \n            if (System.nanoTime() >= stopTime) {\n                return false;\n            }\n            \n            try {\n                long delay = getFixedDelay() + getRandomDelay();\n                Thread.sleep(delay);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return false;\n            }\n        }\n    }\n    \n    private static long getFixedDelay() {\n        return FIXED_DELAY;\n    }\n    \n    private static long getRandomDelay() {\n        return (long) (random.nextDouble() * RANDOM_DELAY);\n    }\n    \n    static class DollarAmount {\n        private final long amount;\n        \n        public DollarAmount(long amount) {\n            this.amount = amount;\n        }\n        \n        public long getAmount() {\n            return amount;\n        }\n        \n        public DollarAmount add(DollarAmount other) {\n            return new DollarAmount(this.amount + other.amount);\n        }\n        \n        public DollarAmount subtract(DollarAmount other) {\n            return new DollarAmount(this.amount - other.amount);\n        }\n    }\n    \n    static class Account {\n        private final int id;\n        private DollarAmount balance;\n        private final ReentrantLock lock = new ReentrantLock();\n        \n        public Account(int id, DollarAmount initialBalance) {\n            this.id = id;\n            this.balance = initialBalance;\n        }\n        \n        public ReentrantLock getLock() {\n            return lock;\n        }\n        \n        public DollarAmount getBalance() {\n            return balance;\n        }\n        \n        public void debit(DollarAmount amount) {\n            balance = balance.subtract(amount);\n        }\n        \n        public void credit(DollarAmount amount) {\n            balance = balance.add(amount);\n        }\n        \n        public int getId() {\n            return id;\n        }\n    }\n    \n    static class InsufficientFundsException extends Exception {\n        public InsufficientFundsException(String message) {\n            super(message);\n        }\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.Random;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\nimport static java.util.concurrent.TimeUnit.MILLISECONDS;\nimport static java.util.concurrent.TimeUnit.NANOSECONDS;\n\npublic class LLMC {\nprivate static Random rnd = new Random();\n\npublic boolean transferMoney(Account fromAcct,\nAccount toAcct,\nDollarAmount amount,\nlong timeout,\nTimeUnit unit)\nthrows InsufficientFundsException, InterruptedException {\nlong fixedDelay = getFixedDelayComponentNanos(timeout, unit);\nlong randMod = getRandomDelayModulusNanos(timeout, unit);\nlong timeoutNanos = unit.toNanos(timeout);\nlong startTime = System.nanoTime();\n\nwhile (true) {\nif (fromAcct.lock.tryLock()) {\ntry {\nif (toAcct.lock.tryLock()) {\ntry {\nif (fromAcct.getBalance().compareTo(amount) < 0)\nthrow new InsufficientFundsException();\nelse {\nfromAcct.debit(amount);\ntoAcct.credit(amount);\nSystem.out.println(\"Transfer success: $\" + amount.value + \" from \" + fromAcct.id + \" to \" + toAcct.id);\nreturn true;\n}\n} finally {\ntoAcct.lock.unlock();\n}\n}\n} finally {\nfromAcct.lock.unlock();\n}\n}\n\nif (System.nanoTime() - startTime >= timeoutNanos)\nreturn false;\n\nNANOSECONDS.sleep(fixedDelay + rnd.nextLong() % randMod);\n}\n}\n\nprivate static final long DELAY_FIXED = MILLISECONDS.toNanos(1);\nprivate static final long DELAY_RANDOM = MILLISECONDS.toNanos(10);\n\nstatic long getFixedDelayComponentNanos(long timeout, TimeUnit unit) {\nreturn DELAY_FIXED;\n}\n\nstatic long getRandomDelayModulusNanos(long timeout, TimeUnit unit) {\nreturn DELAY_RANDOM;\n}\n\nstatic class DollarAmount implements Comparable<DollarAmount> {\nfinal int value;\n\nDollarAmount(int dollars) {\nthis.value = dollars;\n}\n\npublic int compareTo(DollarAmount other) {\nreturn Integer.compare(this.value, other.value);\n}\n\npublic String toString() {\nreturn \"$\" + value;\n}\n}\n\nstatic class Account {\nfinal Lock lock = new ReentrantLock();\nprivate DollarAmount balance;\nfinal String id;\n\nAccount(String id, DollarAmount initialBalance) {\nthis.id = id;\nthis.balance = initialBalance;\n}\n\nvoid debit(DollarAmount d) {\nbalance = new DollarAmount(balance.value - d.value);\n}\n\nvoid credit(DollarAmount d) {\nbalance = new DollarAmount(balance.value + d.value);\n}\n\nDollarAmount getBalance() {\nreturn balance;\n}\n}\n\nstatic class InsufficientFundsException extends Exception {\npublic InsufficientFundsException() {\nsuper(\"Insufficient funds for transfer.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nAccount accountA = new Account(\"A\", new DollarAmount(100));\nAccount accountB = new Account(\"B\", new DollarAmount(100));\n\nLLMC dao = new LLMC();\n\nThread t1 = new Thread(() -> {\ntry {\nboolean success = dao.transferMoney(accountA, accountB, new DollarAmount(20), 100, MILLISECONDS);\nSystem.out.println(\"T1: Transfer \" + (success ? \"succeeded\" : \"failed\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nThread t2 = new Thread(() -> {\ntry {\nboolean success = dao.transferMoney(accountB, accountA, new DollarAmount(30), 100, MILLISECONDS);\nSystem.out.println(\"T2: Transfer \" + (success ? \"succeeded\" : \"failed\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final balances:\");\nSystem.out.println(\"Account A: \" + accountA.getBalance());\nSystem.out.println(\"Account B: \" + accountB.getBalance());\nSystem.out.println(\"Total threads including main: 3\");\n}\n}",
        "max_depth": "2792",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nDeadlockAvoidanceTransfer.main()\n====================================================== search started: 11/17/25 3:12 PM\nInitial: A1=$1000.00 A2=$500.00\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nBankTransferSystem.main()\n====================================================== search started: 11/17/25 3:12 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nBankTransferSystem.main()\n====================================================== search started: 11/17/25 3:12 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            56.73,
            52.91,
            51.28
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Barrier-based timer. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe BarrierTimer class that implements the Runnable interface and is used to measure the time between two events in a concurrent environment. The class should have three instance variables: a boolean started, and two long values startTime and endTime. When the run() method is called, it records the current time using System.nanoTime(). If this is the first call (i.e., started is false), it sets started to true and stores the time as startTime. On subsequent calls, it updates endTime with the current time. Provide a clear() method that resets the timer by setting started back to false. Also provide a getTime() method that returns the difference between endTime and startTime, representing the elapsed time in nanoseconds. All methods must be synchronized to ensure thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class BarrierTimerDemo {\n    public static void main(String[] args) throws InterruptedException {\n        BarrierTimer timer = new BarrierTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        Thread.sleep(100);\n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Elapsed time: \" + timer.getTime() + \" nanoseconds\");\n    }\n}\n\nclass BarrierTimer implements Runnable {\n    private boolean started;\n    private long startTime;\n    private long endTime;\n    \n    public BarrierTimer() {\n        this.started = false;\n        this.startTime = 0;\n        this.endTime = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!started) {\n            started = true;\n            startTime = currentTime;\n        } else {\n            endTime = currentTime;\n        }\n    }\n    \n    public synchronized void clear() {\n        started = false;\n    }\n    \n    public synchronized long getTime() {\n        return endTime - startTime;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class BarrierTimerDemo {\n    public static void main(String[] args) throws InterruptedException {\n        BarrierTimer timer = new BarrierTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            timer.run();\n            System.out.println(\"First thread executed\");\n        });\n        \n        Thread.sleep(100);\n        \n        executor.submit(() -> {\n            timer.run();\n            System.out.println(\"Second thread executed\");\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Elapsed time: \" + timer.getTime() + \" nanoseconds\");\n        \n        timer.clear();\n        \n        ExecutorService executor2 = Executors.newFixedThreadPool(2);\n        \n        executor2.submit(() -> {\n            timer.run();\n            System.out.println(\"Third thread executed after clear\");\n        });\n        \n        Thread.sleep(50);\n        \n        executor2.submit(() -> {\n            timer.run();\n            System.out.println(\"Fourth thread executed after clear\");\n        });\n        \n        executor2.shutdown();\n        executor2.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Elapsed time after clear: \" + timer.getTime() + \" nanoseconds\");\n    }\n}\n\nclass BarrierTimer implements Runnable {\n    private boolean started;\n    private long startTime;\n    private long endTime;\n    \n    public BarrierTimer() {\n        this.started = false;\n        this.startTime = 0;\n        this.endTime = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!started) {\n            started = true;\n            startTime = currentTime;\n        } else {\n            endTime = currentTime;\n        }\n    }\n    \n    public synchronized void clear() {\n        started = false;\n        startTime = 0;\n        endTime = 0;\n    }\n    \n    public synchronized long getTime() {\n        return endTime - startTime;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class BarrierTimerDemo {\n    public static void main(String[] args) throws InterruptedException {\n        BarrierTimer timer = new BarrierTimer();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(timer);\n        Thread.sleep(100);\n        executor.submit(timer);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Elapsed time: \" + timer.getTime() + \" nanoseconds\");\n    }\n}\n\nclass BarrierTimer implements Runnable {\n    private boolean started;\n    private long startTime;\n    private long endTime;\n    \n    public BarrierTimer() {\n        this.started = false;\n        this.startTime = 0;\n        this.endTime = 0;\n    }\n    \n    @Override\n    public synchronized void run() {\n        long currentTime = System.nanoTime();\n        if (!started) {\n            started = true;\n            startTime = currentTime;\n        } else {\n            endTime = currentTime;\n        }\n    }\n    \n    public synchronized void clear() {\n        started = false;\n    }\n    \n    public synchronized long getTime() {\n        return endTime - startTime;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class BarrierTimer implements Runnable {\nprivate boolean started;\nprivate long startTime, endTime;\n\npublic synchronized void run() {\nlong t = System.nanoTime();\nif (!started) {\nstarted = true;\nstartTime = t;\n} else {\nendTime = t;\n}\n}\n\npublic synchronized void clear() {\nstarted = false;\n}\n\npublic synchronized long getTime() {\nreturn endTime - startTime;\n}\n\npublic synchronized double getMillisTime() {\nreturn getTime() / 1_000_000.0;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal BarrierTimer timer = new BarrierTimer();\n\nThread starter = new Thread(() -> {\ntimer.run();\n});\n\nThread stopper = new Thread(() -> {\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\ntimer.run();\n});\n\nstarter.start();\nstopper.start();\n\nstarter.join();\nstopper.join();\n\nSystem.out.println(\"Elapsed time in nanoseconds: \" + timer.getTime());\nSystem.out.println(\"Elapsed time in milliseconds: \" + timer.getMillisTime());\n\ntimer.clear();\n}\n}",
        "max_depth": "166",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 35.98%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 62.02%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 62.10%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=184807,visited=150036,backtracked=333184,end=69\nsearch:             maxDepth=1660,constraints=106598\nchoice generators:  thread=125130 (signal=0,lock=6180,sharedRef=108114,threadApi=3,reschedule=7550), data=0\nheap:               new=209034,released=171325,maxLive=718,gcCycles=297367\ninstructions:       13870271\nmax memory:         1019MB\nloaded code:        classes=137,methods=2409\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 39.43%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.04%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.13%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 1.91%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 0.81%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=182210,visited=149258,backtracked=329808,end=0\nsearch:             maxDepth=1660,constraints=109243\nchoice generators:  thread=120022 (signal=0,lock=8285,sharedRef=102468,threadApi=265,reschedule=5477), data=0\nheap:               new=282402,released=98381,maxLive=775,gcCycles=259396\ninstructions:       14318309\nmax memory:         1019MB\nloaded code:        classes=137,methods=2417\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 36.05%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 62.05%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 62.11%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=191039,visited=155117,backtracked=344496,end=71\nsearch:             maxDepth=1660,constraints=110293\nchoice generators:  thread=129311 (signal=0,lock=6400,sharedRef=111591,threadApi=3,reschedule=7924), data=0\nheap:               new=215273,released=177793,maxLive=718,gcCycles=307486\ninstructions:       14286917\nmax memory:         1020MB\nloaded code:        classes=137,methods=2409\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            56.63,
            70.54,
            56.63
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Bounded buffer using Semaphore. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java implementation of a bounded buffer (circular buffer) using semaphores for synchronization. The buffer should support concurrent access from multiple threads, ensuring thread-safe insertion and removal operations. Use two semaphores to track the number of available items and remaining spaces in the buffer. Implement methods put(E x) to insert an item into the buffer and take() to remove and return an item from the buffer, both blocking when necessary until space or data becomes available. Also include helper methods isEmpty() and isFull() to check the current state of the buffer. Ensure that internal buffer manipulation is synchronized to prevent race conditions during concurrent access. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass BoundedBuffer<E> {\n    private final E[] buffer;\n    private final Semaphore availableItems;\n    private final Semaphore availableSpaces;\n    private int putIndex = 0;\n    private int takeIndex = 0;\n    private final Object lock = new Object();\n\n    @SuppressWarnings(\"unchecked\")\n    public BoundedBuffer(int capacity) {\n        this.buffer = (E[]) new Object[capacity];\n        this.availableItems = new Semaphore(0);\n        this.availableSpaces = new Semaphore(capacity);\n    }\n\n    public void put(E x) throws InterruptedException {\n        availableSpaces.acquire();\n        synchronized (lock) {\n            buffer[putIndex] = x;\n            putIndex = (putIndex + 1) % buffer.length;\n        }\n        availableItems.release();\n    }\n\n    public E take() throws InterruptedException {\n        availableItems.acquire();\n        E item;\n        synchronized (lock) {\n            item = buffer[takeIndex];\n            buffer[takeIndex] = null;\n            takeIndex = (takeIndex + 1) % buffer.length;\n        }\n        availableSpaces.release();\n        return item;\n    }\n\n    public boolean isEmpty() {\n        return availableItems.availablePermits() == 0;\n    }\n\n    public boolean isFull() {\n        return availableSpaces.availablePermits() == 0;\n    }\n}\n\npublic class ConcurrentBoundedBuffer {\n    public static void main(String[] args) {\n        BoundedBuffer<Integer> buffer = new BoundedBuffer<>(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            try {\n                for (int i = 1; i <= 10; i++) {\n                    buffer.put(i);\n                    System.out.println(\"Producer: put \" + i);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Integer value = buffer.take();\n                    System.out.println(\"Consumer: took \" + value);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass BoundedBuffer<E> {\n    private final E[] buffer;\n    private final Semaphore items;\n    private final Semaphore spaces;\n    private final Object lock = new Object();\n    private int putIndex = 0;\n    private int takeIndex = 0;\n    private int count = 0;\n    \n    @SuppressWarnings(\"unchecked\")\n    public BoundedBuffer(int capacity) {\n        buffer = (E[]) new Object[capacity];\n        items = new Semaphore(0);\n        spaces = new Semaphore(capacity);\n    }\n    \n    public void put(E x) throws InterruptedException {\n        spaces.acquire();\n        synchronized (lock) {\n            buffer[putIndex] = x;\n            putIndex = (putIndex + 1) % buffer.length;\n            count++;\n        }\n        items.release();\n    }\n    \n    public E take() throws InterruptedException {\n        items.acquire();\n        E item;\n        synchronized (lock) {\n            item = buffer[takeIndex];\n            buffer[takeIndex] = null;\n            takeIndex = (takeIndex + 1) % buffer.length;\n            count--;\n        }\n        spaces.release();\n        return item;\n    }\n    \n    public boolean isEmpty() {\n        synchronized (lock) {\n            return count == 0;\n        }\n    }\n    \n    public boolean isFull() {\n        synchronized (lock) {\n            return count == buffer.length;\n        }\n    }\n}\n\npublic class BoundedBufferDemo {\n    public static void main(String[] args) {\n        BoundedBuffer<Integer> buffer = new BoundedBuffer<>(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 1; i <= 10; i++) {\n                    buffer.put(i);\n                    System.out.println(\"Produced: \" + i);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Integer value = buffer.take();\n                    System.out.println(\"Consumed: \" + value);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.Semaphore;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class BoundedBuffer<E> {\n    private final E[] buffer;\n    private final Semaphore availableItems;\n    private final Semaphore availableSpaces;\n    private int putIndex = 0;\n    private int takeIndex = 0;\n    private final Object lock = new Object();\n\n    @SuppressWarnings(\"unchecked\")\n    public BoundedBuffer(int capacity) {\n        buffer = (E[]) new Object[capacity];\n        availableItems = new Semaphore(0);\n        availableSpaces = new Semaphore(capacity);\n    }\n\n    public void put(E item) throws InterruptedException {\n        availableSpaces.acquire();\n        synchronized (lock) {\n            buffer[putIndex] = item;\n            putIndex = (putIndex + 1) % buffer.length;\n        }\n        availableItems.release();\n    }\n\n    public E take() throws InterruptedException {\n        availableItems.acquire();\n        E item;\n        synchronized (lock) {\n            item = buffer[takeIndex];\n            buffer[takeIndex] = null;\n            takeIndex = (takeIndex + 1) % buffer.length;\n        }\n        availableSpaces.release();\n        return item;\n    }\n\n    public boolean isEmpty() {\n        return availableItems.availablePermits() == 0;\n    }\n\n    public boolean isFull() {\n        return availableSpaces.availablePermits() == 0;\n    }\n\n    public static void main(String[] args) {\n        BoundedBuffer<Integer> buffer = new BoundedBuffer<>(5);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            try {\n                for (int i = 1; i <= 10; i++) {\n                    buffer.put(i);\n                    System.out.println(\"Produced: \" + i);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    Integer value = buffer.take();\n                    System.out.println(\"Consumed: \" + value);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.concurrent.Semaphore;\n\npublic class SemaphoreBoundedBuffer<E> {\nprivate final Semaphore availableItems, availableSpaces;\nprivate final E[] items;\nprivate int putPosition = 0, takePosition = 0;\n\npublic SemaphoreBoundedBuffer(int capacity) {\nif (capacity <= 0) throw new IllegalArgumentException();\navailableItems = new Semaphore(0);\navailableSpaces = new Semaphore(capacity);\nitems = (E[]) new Object[capacity];\n}\n\npublic void put(E x) throws InterruptedException {\navailableSpaces.acquire();\nsynchronized (this) {\nitems[putPosition] = x;\nputPosition = (putPosition + 1) % items.length;\n}\navailableItems.release();\n}\n\npublic E take() throws InterruptedException {\navailableItems.acquire();\nE item;\nsynchronized (this) {\nitem = items[takePosition];\nitems[takePosition] = null;\ntakePosition = (takePosition + 1) % items.length;\n}\navailableSpaces.release();\nreturn item;\n}\n\npublic static void main(String[] args) {\nfinal int bufferSize = 2;\nfinal int numItems = 2;\n\nSemaphoreBoundedBuffer<Integer> buffer = new SemaphoreBoundedBuffer<>(bufferSize);\n\nThread producer = new Thread(() -> {\ntry {\nfor (int i = 0; i < numItems; i++) {\nbuffer.put(i);\n// Avoid printing to reduce state space\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n\nThread consumer = new Thread(() -> {\ntry {\nfor (int i = 0; i < numItems; i++) {\nInteger item = buffer.take();\n// Avoid printing to reduce state space\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n\nproducer.start();\nconsumer.start();\n\ntry {\nproducer.join();\nconsumer.join();\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n\n// Minimal output\nSystem.out.println(\"Done.\");\n}\n}",
        "max_depth": "71",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nConcurrentBoundedBuffer.main()\n====================================================== search started: 11/17/25 3:13 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nBoundedBufferDemo.main()\n====================================================== search started: 11/17/25 3:14 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nBoundedBuffer.main()\n====================================================== search started: 11/17/25 3:14 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            55.97,
            57.4,
            59.82
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Caching the last result using a volatile reference to an immutable holder object. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java servlet that caches the result of a computation using a volatile reference to an immutable cache object. The servlet should handle requests by extracting a BigInteger value from the request, checking if the cached result matches the input value, and if not, recompute the result and update the cache. The computation in this case is a placeholder that simply returns the input value as a single-element array. The cache should be thread-safe and implemented as an immutable helper class. Use a volatile variable to hold the cache reference to ensure visibility across threads. Include appropriate annotations and structure to indicate thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.math.BigInteger;\nimport java.util.Arrays;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CachingServlet {\n    \n    private volatile OneValueCache cache = new OneValueCache(null, null);\n    \n    public void service(ServletRequest req, ServletResponse resp) {\n        BigInteger i = extractFromRequest(req);\n        BigInteger[] factors = cache.getFactors(i);\n        if (factors == null) {\n            factors = factor(i);\n            cache = new OneValueCache(i, factors);\n        }\n        encodeIntoResponse(resp, factors);\n    }\n    \n    private BigInteger extractFromRequest(ServletRequest req) {\n        return req.getValue();\n    }\n    \n    private void encodeIntoResponse(ServletResponse resp, BigInteger[] factors) {\n        resp.setResult(factors);\n    }\n    \n    private BigInteger[] factor(BigInteger i) {\n        return new BigInteger[] { i };\n    }\n    \n    public static void main(String[] args) {\n        CachingServlet servlet = new CachingServlet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            ServletRequest req1 = new ServletRequest(new BigInteger(\"100\"));\n            ServletResponse resp1 = new ServletResponse();\n            servlet.service(req1, resp1);\n            System.out.println(\"Thread 1: \" + Arrays.toString(resp1.getResult()));\n            \n            ServletRequest req2 = new ServletRequest(new BigInteger(\"100\"));\n            ServletResponse resp2 = new ServletResponse();\n            servlet.service(req2, resp2);\n            System.out.println(\"Thread 1 (cached): \" + Arrays.toString(resp2.getResult()));\n        });\n        \n        executor.submit(() -> {\n            ServletRequest req1 = new ServletRequest(new BigInteger(\"200\"));\n            ServletResponse resp1 = new ServletResponse();\n            servlet.service(req1, resp1);\n            System.out.println(\"Thread 2: \" + Arrays.toString(resp1.getResult()));\n            \n            ServletRequest req2 = new ServletRequest(new BigInteger(\"200\"));\n            ServletResponse resp2 = new ServletResponse();\n            servlet.service(req2, resp2);\n            System.out.println(\"Thread 2 (cached): \" + Arrays.toString(resp2.getResult()));\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass OneValueCache {\n    private final BigInteger lastNumber;\n    private final BigInteger[] lastFactors;\n    \n    public OneValueCache(BigInteger i, BigInteger[] factors) {\n        lastNumber = i;\n        lastFactors = factors == null ? null : Arrays.copyOf(factors, factors.length);\n    }\n    \n    public BigInteger[] getFactors(BigInteger i) {\n        if (lastNumber == null || !lastNumber.equals(i))\n            return null;\n        else\n            return Arrays.copyOf(lastFactors, lastFactors.length);\n    }\n}\n\nclass ServletRequest {\n    private final BigInteger value;\n    \n    public ServletRequest(BigInteger value) {\n        this.value = value;\n    }\n    \n    public BigInteger getValue() {\n        return value;\n    }\n}\n\nclass ServletResponse {\n    private BigInteger[] result;\n    \n    public void setResult(BigInteger[] result) {\n        this.result = result;\n    }\n    \n    public BigInteger[] getResult() {\n        return result;\n    }\n}",
            "import java.math.BigInteger;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CachingServlet {\n    \n    private volatile OneValueCache cache = new OneValueCache(null, null);\n    \n    public void service(ServletRequest req, ServletResponse resp) {\n        BigInteger i = extractFromRequest(req);\n        BigInteger[] factors = cache.getFactors(i);\n        if (factors == null) {\n            factors = factor(i);\n            cache = new OneValueCache(i, factors);\n        }\n        encodeIntoResponse(resp, factors);\n    }\n    \n    private BigInteger extractFromRequest(ServletRequest req) {\n        return req.getValue();\n    }\n    \n    private void encodeIntoResponse(ServletResponse resp, BigInteger[] factors) {\n        resp.setFactors(factors);\n    }\n    \n    private BigInteger[] factor(BigInteger i) {\n        return new BigInteger[] { i };\n    }\n    \n    public static void main(String[] args) {\n        CachingServlet servlet = new CachingServlet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            ServletRequest req1 = new ServletRequest(new BigInteger(\"100\"));\n            ServletResponse resp1 = new ServletResponse();\n            servlet.service(req1, resp1);\n            System.out.println(\"Thread 1: \" + resp1.getFactors()[0]);\n        });\n        \n        executor.submit(() -> {\n            ServletRequest req2 = new ServletRequest(new BigInteger(\"200\"));\n            ServletResponse resp2 = new ServletResponse();\n            servlet.service(req2, resp2);\n            System.out.println(\"Thread 2: \" + resp2.getFactors()[0]);\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nfinal class OneValueCache {\n    private final BigInteger lastNumber;\n    private final BigInteger[] lastFactors;\n    \n    public OneValueCache(BigInteger i, BigInteger[] factors) {\n        lastNumber = i;\n        lastFactors = factors;\n    }\n    \n    public BigInteger[] getFactors(BigInteger i) {\n        if (lastNumber == null || !lastNumber.equals(i))\n            return null;\n        else\n            return lastFactors.clone();\n    }\n}\n\nclass ServletRequest {\n    private final BigInteger value;\n    \n    public ServletRequest(BigInteger value) {\n        this.value = value;\n    }\n    \n    public BigInteger getValue() {\n        return value;\n    }\n}\n\nclass ServletResponse {\n    private BigInteger[] factors;\n    \n    public void setFactors(BigInteger[] factors) {\n        this.factors = factors;\n    }\n    \n    public BigInteger[] getFactors() {\n        return factors;\n    }\n}",
            "import java.math.BigInteger;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CachingServlet {\n    \n    private volatile OneValueCache cache = new OneValueCache(null, null);\n    \n    public void service(ServletRequest req, ServletResponse resp) {\n        BigInteger i = extractFromRequest(req);\n        BigInteger[] factors = cache.getFactors(i);\n        if (factors == null) {\n            factors = factor(i);\n            cache = new OneValueCache(i, factors);\n        }\n        encodeIntoResponse(resp, factors);\n    }\n    \n    private BigInteger extractFromRequest(ServletRequest req) {\n        return req.getValue();\n    }\n    \n    private void encodeIntoResponse(ServletResponse resp, BigInteger[] factors) {\n        resp.setFactors(factors);\n    }\n    \n    private BigInteger[] factor(BigInteger i) {\n        return new BigInteger[] { i };\n    }\n    \n    public static void main(String[] args) {\n        CachingServlet servlet = new CachingServlet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                ServletRequest req = new ServletRequest(BigInteger.valueOf(100 + i));\n                ServletResponse resp = new ServletResponse();\n                servlet.service(req, resp);\n                System.out.println(\"Thread 1 - Request: \" + req.getValue() + \n                                 \", Response: \" + resp.getFactors()[0]);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                ServletRequest req = new ServletRequest(BigInteger.valueOf(200 + i));\n                ServletResponse resp = new ServletResponse();\n                servlet.service(req, resp);\n                System.out.println(\"Thread 2 - Request: \" + req.getValue() + \n                                 \", Response: \" + resp.getFactors()[0]);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nfinal class OneValueCache {\n    private final BigInteger lastNumber;\n    private final BigInteger[] lastFactors;\n    \n    public OneValueCache(BigInteger i, BigInteger[] factors) {\n        lastNumber = i;\n        lastFactors = factors;\n    }\n    \n    public BigInteger[] getFactors(BigInteger i) {\n        if (lastNumber == null || !lastNumber.equals(i)) {\n            return null;\n        } else {\n            return lastFactors.clone();\n        }\n    }\n}\n\nclass ServletRequest {\n    private final BigInteger value;\n    \n    public ServletRequest(BigInteger value) {\n        this.value = value;\n    }\n    \n    public BigInteger getValue() {\n        return value;\n    }\n}\n\nclass ServletResponse {\n    private BigInteger[] factors;\n    \n    public void setFactors(BigInteger[] factors) {\n        this.factors = factors;\n    }\n    \n    public BigInteger[] getFactors() {\n        return factors;\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.math.BigInteger;\n\npublic class VolatileCachedFactorizer {\n\nprivate volatile OneValueCache cache = new OneValueCache(null, null);\n\npublic void service(BigInteger input) {\nBigInteger[] factors = cache.getFactors(input);\nif (factors == null) {\nfactors = factor(input);\ncache = new OneValueCache(input, factors);\nSystem.out.println(Thread.currentThread().getName() + \": computed and cached \" + input);\n} else {\nSystem.out.println(Thread.currentThread().getName() + \": cache hit for \" + input);\n}\nencodeIntoResponse(factors);\n}\n\nvoid encodeIntoResponse(BigInteger[] factors) {\nSystem.out.println(Thread.currentThread().getName() + \": response = \" + factors[0]);\n}\n\nBigInteger[] factor(BigInteger i) {\nreturn new BigInteger[]{i};\n}\n\nprivate static final class OneValueCache {\nprivate final BigInteger lastNumber;\nprivate final BigInteger[] lastFactors;\n\npublic OneValueCache(BigInteger number, BigInteger[] factors) {\nthis.lastNumber = number;\nthis.lastFactors = (factors == null) ? null : factors.clone();\n}\n\npublic BigInteger[] getFactors(BigInteger input) {\nif (lastNumber == null || !lastNumber.equals(input)) {\nreturn null;\n}\nreturn lastFactors.clone();\n}\n}\n\npublic static void main(String[] args) {\nfinal VolatileCachedFactorizer servlet = new VolatileCachedFactorizer();\n\nThread t1 = new Thread(() -> servlet.service(new BigInteger(\"3\")), \"T1\");\nThread t2 = new Thread(() -> servlet.service(new BigInteger(\"5\")), \"T2\");\n\nt1.start();\nt2.start();\n\ntry {\nt1.join();\nt2.join();\n} catch (InterruptedException e) {\nSystem.out.println(\"Interrupted\");\n}\n}\n}",
        "max_depth": "80",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.78%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.78%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field CachingServlet@1c3.cache   pool-1-t...\"\n\n====================================================== statistics\nstates:             new=95069,visited=29879,backtracked=124148,end=0\nsearch:             maxDepth=800,constraints=60834\nchoice generators:  thread=42393 (signal=0,lock=1363,sharedRef=27823,threadApi=2,reschedule=323), data=0\nheap:               new=188178,released=93916,maxLive=1146,gcCycles=124727\ninstructions:       10199753\nmax memory:         1007MB\nloaded code:        classes=141,methods=2836\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.79%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.79%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field CachingServlet@1c3.cache   pool-1-t...\"\n\n====================================================== statistics\nstates:             new=94481,visited=28641,backtracked=122322,end=0\nsearch:             maxDepth=800,constraints=60865\nchoice generators:  thread=41772 (signal=0,lock=1220,sharedRef=27363,threadApi=2,reschedule=272), data=0\nheap:               new=173939,released=83944,maxLive=1134,gcCycles=122874\ninstructions:       9731385\nmax memory:         1006MB\nloaded code:        classes=140,methods=2812\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.93%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.93%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field CachingServlet@1c3.cache   pool-1-t...\"\n\n====================================================== statistics\nstates:             new=89184,visited=20072,backtracked=108456,end=0\nsearch:             maxDepth=800,constraints=59977\nchoice generators:  thread=37049 (signal=0,lock=797,sharedRef=23291,threadApi=2,reschedule=19), data=0\nheap:               new=102086,released=37727,maxLive=1123,gcCycles=109236\ninstructions:       6829922\nmax memory:         1004MB\nloaded code:        classes=140,methods=2812\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field CachingServlet@1c3.cache   pool-1-t...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field CachingServlet@1c3.cache   pool-1-t...\"",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field CachingServlet@1c3.cache   pool-1-t...\""
        ],
        "codebleu_score": [
            57.71,
            59.54,
            59.85
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Candidate for lock elision. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named ThreeStooges that represents an immutable collection of the names of the Three Stooges: \"Moe\", \"Larry\", and \"Curly\". The class should provide two methods:\n\nA method isStooge(String name) that returns true if the given name is one of the Three Stooges, and false otherwise.\nA method getStoogeNames() that returns a string representation of a list containing the names of the Three Stooges in the order \"Moe\", \"Larry\", \"Curly\".\nEnsure that all fields are properly encapsulated and that the class cannot be modified after construction. Do not make the class thread-unsafe; however, avoid unnecessary synchronization where possible. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.HashSet;\nimport java.util.List;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic final class ThreeStooges {\n    private final Set<String> stooges;\n    private final List<String> stoogeList;\n    \n    public ThreeStooges() {\n        List<String> names = Arrays.asList(\"Moe\", \"Larry\", \"Curly\");\n        this.stoogeList = Collections.unmodifiableList(names);\n        this.stooges = Collections.unmodifiableSet(new HashSet<>(names));\n    }\n    \n    public boolean isStooge(String name) {\n        return stooges.contains(name);\n    }\n    \n    public String getStoogeNames() {\n        return stoogeList.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        ThreeStooges threeStooges = new ThreeStooges();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            String[] testNames = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\", \"Joe\"};\n            for (String name : testNames) {\n                boolean result = threeStooges.isStooge(name);\n                System.out.println(\"Thread 1: Is \" + name + \" a stooge? \" + result);\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 3; i++) {\n                String names = threeStooges.getStoogeNames();\n                System.out.println(\"Thread 2: Stooge names: \" + names);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.HashSet;\nimport java.util.List;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ThreeStooges {\n    private final Set<String> stooges;\n    private final List<String> stoogeList;\n    \n    public ThreeStooges() {\n        List<String> names = Arrays.asList(\"Moe\", \"Larry\", \"Curly\");\n        this.stoogeList = Collections.unmodifiableList(names);\n        this.stooges = Collections.unmodifiableSet(new HashSet<>(names));\n    }\n    \n    public boolean isStooge(String name) {\n        return stooges.contains(name);\n    }\n    \n    public String getStoogeNames() {\n        return stoogeList.toString();\n    }\n    \n    public static void main(String[] args) {\n        ThreeStooges threeStooges = new ThreeStooges();\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Is Moe a stooge? \" + threeStooges.isStooge(\"Moe\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Is Larry a stooge? \" + threeStooges.isStooge(\"Larry\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 3: Is Curly a stooge? \" + threeStooges.isStooge(\"Curly\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 4: Is Shemp a stooge? \" + threeStooges.isStooge(\"Shemp\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 5: Stooge names: \" + threeStooges.getStoogeNames());\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.Arrays;\nimport java.util.Collections;\nimport java.util.HashSet;\nimport java.util.List;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ThreeStooges {\n    private final Set<String> stooges;\n    private final List<String> stoogeList;\n    \n    public ThreeStooges() {\n        this.stoogeList = Collections.unmodifiableList(Arrays.asList(\"Moe\", \"Larry\", \"Curly\"));\n        this.stooges = Collections.unmodifiableSet(new HashSet<>(stoogeList));\n    }\n    \n    public boolean isStooge(String name) {\n        return stooges.contains(name);\n    }\n    \n    public String getStoogeNames() {\n        return stoogeList.toString();\n    }\n    \n    public static void main(String[] args) {\n        ThreeStooges threeStooges = new ThreeStooges();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 1: Checking if Moe is a stooge: \" + threeStooges.isStooge(\"Moe\"));\n            System.out.println(\"Thread 1: Checking if Larry is a stooge: \" + threeStooges.isStooge(\"Larry\"));\n            System.out.println(\"Thread 1: Checking if Bob is a stooge: \" + threeStooges.isStooge(\"Bob\"));\n        });\n        \n        executor.submit(() -> {\n            System.out.println(\"Thread 2: Stooge names: \" + threeStooges.getStoogeNames());\n            System.out.println(\"Thread 2: Checking if Curly is a stooge: \" + threeStooges.isStooge(\"Curly\"));\n            System.out.println(\"Thread 2: Checking if Alice is a stooge: \" + threeStooges.isStooge(\"Alice\"));\n        });\n        \n        System.out.println(\"Main thread: Stooge names: \" + threeStooges.getStoogeNames());\n        System.out.println(\"Main thread: Checking if Moe is a stooge: \" + threeStooges.isStooge(\"Moe\"));\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic final class ThreeStooges {\nprivate static final List<String> STOOGES =\nCollections.unmodifiableList(Arrays.asList(\"Moe\", \"Larry\", \"Curly\"));\nprivate static final Set<String> STOOGES_SET = new HashSet<>(STOOGES);\n\npublic boolean isStooge(String name) {\nreturn STOOGES_SET.contains(name);\n}\n\npublic String getStoogeNames() {\nreturn STOOGES.toString();\n}\n\npublic static void main(String[] args) {\nfinal ThreeStooges stooges = new ThreeStooges();\n\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nString[] namesToCheck = {\"Moe\", \"Shemp\", \"Larry\", \"Curly\", \"John\", \"Curly\", \"Moe\"};\n\nfor (int i = 0; i < namesToCheck.length; i++) {\nfinal int taskId = i;\nfinal String name = namesToCheck[i];\nexecutor.submit(new StoogeCheckerTask(stooges, name, taskId));\n}\n\nexecutor.shutdown();\n}\n}\n\nclass StoogeCheckerTask implements Runnable {\nprivate final ThreeStooges stooges;\nprivate final String name;\nprivate final int taskId;\n\npublic StoogeCheckerTask(ThreeStooges stooges, String name, int taskId) {\nthis.stooges = stooges;\nthis.name = name;\nthis.taskId = taskId;\n}\n\n@Override\npublic void run() {\nSystem.out.println(\"Task ID: \" + taskId + \" - Checking name: \" + name);\nboolean result = stooges.isStooge(name);\nSystem.out.println(\"Task ID: \" + taskId + \" - Is '\" + name + \"' a stooge? \" + result);\n}\n}",
        "max_depth": "158",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.50%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.44%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.58%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=152994,visited=142774,backtracked=294247,end=57\nsearch:             maxDepth=1580,constraints=60901\nchoice generators:  thread=100565 (signal=0,lock=4,sharedRef=62585,threadApi=5298,reschedule=19286), data=0\nheap:               new=274263,released=614706,maxLive=772,gcCycles=295768\ninstructions:       34264292\nmax memory:         1018MB\nloaded code:        classes=143,methods=2651\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.58%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.58%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.55%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.55%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.55%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=82842,visited=189882,backtracked=271147,end=3\nsearch:             maxDepth=1580,constraints=87320\nchoice generators:  thread=47113 (signal=0,lock=7,sharedRef=43947,threadApi=5,reschedule=1180), data=0\nheap:               new=98585,released=277763,maxLive=805,gcCycles=272724\ninstructions:       23910428\nmax memory:         1019MB\nloaded code:        classes=143,methods=2657\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.39%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.05%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.15%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=147788,visited=136586,backtracked=282874,end=92\nsearch:             maxDepth=1580,constraints=58540\nchoice generators:  thread=97172 (signal=0,lock=4,sharedRef=68491,threadApi=2,reschedule=15490), data=0\nheap:               new=281256,released=615674,maxLive=783,gcCycles=284374\ninstructions:       35327349\nmax memory:         1018MB\nloaded code:        classes=144,methods=2656\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            55.45,
            52.16,
            51.68
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Candidate for lock splitting. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a class named ServerStatusBeforeSplit that maintains two sets of strings: one for users and one for queries. Both sets should be initialized in the constructor using HashSet<String>. All modification methods—such as adding or removing a user or query—should be synchronized on the instance (this) to ensure thread safety when multiple threads access the class concurrently. Provide four synchronized methods: addUser(String u), addQuery(String q), removeUser(String u), and removeQuery(String q)—each performing the corresponding operation on its respective set. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ServerStatusBeforeSplit {\n    private final Set<String> users;\n    private final Set<String> queries;\n\n    public ServerStatusBeforeSplit() {\n        this.users = new HashSet<String>();\n        this.queries = new HashSet<String>();\n    }\n\n    public synchronized void addUser(String u) {\n        users.add(u);\n    }\n\n    public synchronized void addQuery(String q) {\n        queries.add(q);\n    }\n\n    public synchronized void removeUser(String u) {\n        users.remove(u);\n    }\n\n    public synchronized void removeQuery(String q) {\n        queries.remove(q);\n    }\n\n    public synchronized int getUserCount() {\n        return users.size();\n    }\n\n    public synchronized int getQueryCount() {\n        return queries.size();\n    }\n\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 10 == 0) {\n                    System.out.println(\"Thread 1: Added user\" + i + \" and query\" + i);\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 50; i < 150; i++) {\n                server.addUser(\"user\" + i);\n                server.removeQuery(\"query\" + (i - 50));\n                if (i % 10 == 0) {\n                    System.out.println(\"Thread 2: Added user\" + i + \" and removed query\" + (i - 50));\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Final user count: \" + server.getUserCount());\n        System.out.println(\"Final query count: \" + server.getQueryCount());\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> users;\n    private final Set<String> queries;\n    \n    public ServerStatusBeforeSplit() {\n        this.users = new HashSet<String>();\n        this.queries = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        users.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        queries.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        users.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        queries.remove(q);\n    }\n    \n    public synchronized int getUserCount() {\n        return users.size();\n    }\n    \n    public synchronized int getQueryCount() {\n        return queries.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 10 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 15 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Users: \" + server.getUserCount());\n        System.out.println(\"Queries: \" + server.getQueryCount());\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusBeforeSplit {\n    private final Set<String> users;\n    private final Set<String> queries;\n    \n    public ServerStatusBeforeSplit() {\n        this.users = new HashSet<String>();\n        this.queries = new HashSet<String>();\n    }\n    \n    public synchronized void addUser(String u) {\n        users.add(u);\n    }\n    \n    public synchronized void addQuery(String q) {\n        queries.add(q);\n    }\n    \n    public synchronized void removeUser(String u) {\n        users.remove(u);\n    }\n    \n    public synchronized void removeQuery(String q) {\n        queries.remove(q);\n    }\n    \n    public synchronized int getUserCount() {\n        return users.size();\n    }\n    \n    public synchronized int getQueryCount() {\n        return queries.size();\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusBeforeSplit server = new ServerStatusBeforeSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 2 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                server.addUser(\"user\" + i);\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Users: \" + server.getUserCount());\n        System.out.println(\"Queries: \" + server.getQueryCount());\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.HashSet;\nimport java.util.Set;\n\npublic class ServerStatusBeforeSplit {\npublic final Set<String> users;\npublic final Set<String> queries;\n\npublic ServerStatusBeforeSplit() {\nusers = new HashSet<>();\nqueries = new HashSet<>();\n}\n\npublic synchronized void addUser(String u) {\nusers.add(u);\n}\n\npublic synchronized void addQuery(String q) {\nqueries.add(q);\n}\n\npublic synchronized void removeUser(String u) {\nusers.remove(u);\n}\n\npublic synchronized void removeQuery(String q) {\nqueries.remove(q);\n}\n\npublic synchronized Set<String> getActiveUsers() {\nreturn new HashSet<>(users);\n}\n\npublic synchronized Set<String> getActiveQueries() {\nreturn new HashSet<>(queries);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nServerStatusBeforeSplit status = new ServerStatusBeforeSplit();\n\nThread t1 = new Thread(() -> {\nstatus.addUser(\"user1\");\nstatus.addQuery(\"query1\");\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user1\");\nstatus.removeQuery(\"query1\");\n});\n\nThread t2 = new Thread(() -> {\nstatus.addUser(\"user2\");\nstatus.addQuery(\"query2\");\ntry {\nThread.sleep(300);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user2\");\nstatus.removeQuery(\"query2\");\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final active users: \" + status.getActiveUsers());\nSystem.out.println(\"Final active queries: \" + status.getActiveQueries());\n}\n}",
        "max_depth": "89",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nServerStatusBeforeSplit.main()\n====================================================== search started: 11/17/25 3:16 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/17/25 3:16 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/17/25 3:16 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            56.89,
            58.74,
            58.74
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Counting sheep. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that simulates a person trying to fall asleep by repeatedly counting sheep. The program should include a class with a volatile boolean variable called \"asleep\" to indicate whether the person is asleep. It should also have a method named \"tryToSleep\" which contains a loop that continues as long as \"asleep\" is false. Inside the loop, it should call another method named \"countSomeSheep\". Implement the \"countSomeSheep\" method to represent the action of counting sheep, though its exact implementation can be left empty or contain a simple comment indicating the counting action. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools.\nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SleepSimulator {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        // Counting sheep\n    }\n    \n    public void fallAsleep() {\n        try {\n            Thread.sleep(3000);\n            asleep = true;\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        SleepSimulator simulator = new SleepSimulator();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> simulator.tryToSleep());\n        executor.submit(() -> simulator.fallAsleep());\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SleepSimulator {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        // Counting sheep\n    }\n    \n    public void fallAsleep() {\n        try {\n            Thread.sleep(2000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        asleep = true;\n    }\n    \n    public static void main(String[] args) {\n        SleepSimulator simulator = new SleepSimulator();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> simulator.tryToSleep());\n        executor.submit(() -> simulator.fallAsleep());\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SleepSimulator {\n    private volatile boolean asleep = false;\n    \n    public void tryToSleep() {\n        while (!asleep) {\n            countSomeSheep();\n        }\n    }\n    \n    private void countSomeSheep() {\n        // Counting sheep\n    }\n    \n    public void fallAsleep() {\n        asleep = true;\n    }\n    \n    public static void main(String[] args) {\n        SleepSimulator simulator = new SleepSimulator();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            simulator.tryToSleep();\n            System.out.println(\"Finally asleep!\");\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(1000);\n                simulator.fallAsleep();\n                System.out.println(\"Time to sleep!\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "public class CountingSheep {\n  private boolean asleep;\n\n  synchronized void tryToSleep() {\n    while (!isAsleep()) {\n      countSomeSheep();\n    }\n  }\n\n  synchronized boolean isAsleep() {\n    return asleep;\n  }\n\n  synchronized void setAsleep(boolean value) {\n    asleep = value;\n  }\n\n  void countSomeSheep() {\n    System.out.println(\"Counting sheep...\");\n    try {\n      Thread.sleep(100);\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n  }\n\n  public static void main(String[] args) {\n    CountingSheep counter = new CountingSheep();\n\n    Thread sheepThread = new Thread(() -> {\n      System.out.println(\"Sheep is trying to sleep...\");\n      counter.tryToSleep();\n      System.out.println(\"Sheep has fallen asleep.\");\n    });\n\n    Thread controllerThread = new Thread(() -> {\n      try {\n        Thread.sleep(200);\n        System.out.println(\"Setting asleep = true\");\n        counter.setAsleep(true);\n      } catch (InterruptedException e) {\n        Thread.currentThread().interrupt();\n      }\n    });\n\n    sheepThread.start();\n    controllerThread.start();\n\n    try {\n      sheepThread.join();\n      controllerThread.join();\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n\n    System.out.println(\"Main thread finished.\");\n  }\n}",
        "max_depth": "15",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nSleepSimulator.main()\n====================================================== search started: 11/17/25 3:16 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nSleepSimulator.main()\n====================================================== search started: 11/17/25 3:17 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nSleepSimulator.main()\n====================================================== search started: 11/17/25 3:17 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            52.83,
            53.53,
            58.42
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Custom thread base class. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a custom MyAppThread class that extends Thread and provides enhanced lifecycle tracking and error handling for application threads. The class should use a static String constant DEFAULT_NAME = \"MyAppThread\" as the default thread name prefix. Each thread should be assigned a unique name by appending an auto-incrementing number from a shared AtomicInteger. Set up an uncaught exception handler to log severe errors using a static Logger, including the thread name and exception details. Override the run() method to optionally log the creation and termination of each thread based on a static volatile boolean flag debugLifecycle. Also, maintain two atomic counters: one for total threads created (created) and one for currently active threads (alive). These counters should be updated in run(), with alive incremented before calling super.run() and decremented in a finally block. Provide public static getter methods for these counters and a setDebug(boolean) method to enable or disable debug logging. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.atomic.AtomicInteger;\nimport java.util.logging.Logger;\nimport java.util.logging.Level;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MyAppThread extends Thread {\n    private static final String DEFAULT_NAME = \"MyAppThread\";\n    private static final AtomicInteger threadNumber = new AtomicInteger(0);\n    private static final Logger logger = Logger.getLogger(MyAppThread.class.getName());\n    private static volatile boolean debugLifecycle = false;\n    private static final AtomicInteger created = new AtomicInteger(0);\n    private static final AtomicInteger alive = new AtomicInteger(0);\n    \n    public MyAppThread() {\n        this(null);\n    }\n    \n    public MyAppThread(Runnable target) {\n        super(target, DEFAULT_NAME + \"-\" + threadNumber.incrementAndGet());\n        setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {\n            @Override\n            public void uncaughtException(Thread t, Throwable e) {\n                logger.log(Level.SEVERE, \"Thread \" + t.getName() + \" died with exception\", e);\n            }\n        });\n    }\n    \n    @Override\n    public void run() {\n        created.incrementAndGet();\n        alive.incrementAndGet();\n        \n        if (debugLifecycle) {\n            logger.log(Level.INFO, \"Created \" + getName());\n        }\n        \n        try {\n            super.run();\n        } finally {\n            alive.decrementAndGet();\n            if (debugLifecycle) {\n                logger.log(Level.INFO, \"Terminating \" + getName());\n            }\n        }\n    }\n    \n    public static int getCreated() {\n        return created.get();\n    }\n    \n    public static int getAlive() {\n        return alive.get();\n    }\n    \n    public static void setDebug(boolean debug) {\n        debugLifecycle = debug;\n    }\n    \n    public static void main(String[] args) {\n        MyAppThread.setDebug(true);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        MyAppThread thread1 = new MyAppThread(() -> {\n            try {\n                Thread.sleep(100);\n                System.out.println(\"Task 1 completed\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        MyAppThread thread2 = new MyAppThread(() -> {\n            try {\n                Thread.sleep(200);\n                System.out.println(\"Task 2 completed\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        thread1.start();\n        thread2.start();\n        \n        executor.submit(() -> {\n            MyAppThread thread3 = new MyAppThread(() -> {\n                System.out.println(\"Task 3 completed\");\n            });\n            thread3.start();\n            try {\n                thread3.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.submit(() -> {\n            MyAppThread thread4 = new MyAppThread(() -> {\n                throw new RuntimeException(\"Intentional error for testing\");\n            });\n            thread4.start();\n            try {\n                thread4.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        executor.submit(() -> {\n            MyAppThread thread5 = new MyAppThread(() -> {\n                System.out.println(\"Task 5 completed\");\n            });\n            thread5.start();\n            try {\n                thread5.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        try {\n            thread1.join();\n            thread2.join();\n            executor.shutdown();\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n            \n            Thread.sleep(500);\n            System.out.println(\"Total threads created: \" + MyAppThread.getCreated());\n            System.out.println(\"Currently alive threads: \" + MyAppThread.getAlive());\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.atomic.AtomicInteger;\nimport java.util.logging.Logger;\nimport java.util.logging.Level;\n\npublic class MyAppThread extends Thread {\n    private static final String DEFAULT_NAME = \"MyAppThread\";\n    private static final AtomicInteger threadNumber = new AtomicInteger(0);\n    private static final AtomicInteger created = new AtomicInteger(0);\n    private static final AtomicInteger alive = new AtomicInteger(0);\n    private static volatile boolean debugLifecycle = false;\n    private static final Logger logger = Logger.getLogger(MyAppThread.class.getName());\n    \n    static {\n        Thread.setDefaultUncaughtExceptionHandler((thread, exception) -> {\n            logger.log(Level.SEVERE, \"Thread \" + thread.getName() + \" threw exception: \" + exception.getMessage(), exception);\n        });\n    }\n    \n    public MyAppThread() {\n        this(null);\n    }\n    \n    public MyAppThread(Runnable target) {\n        super(target, DEFAULT_NAME + \"-\" + threadNumber.incrementAndGet());\n        created.incrementAndGet();\n        setUncaughtExceptionHandler((thread, exception) -> {\n            logger.log(Level.SEVERE, \"Thread \" + thread.getName() + \" threw exception: \" + exception.getMessage(), exception);\n        });\n    }\n    \n    @Override\n    public void run() {\n        if (debugLifecycle) {\n            logger.info(\"Thread \" + getName() + \" created\");\n        }\n        alive.incrementAndGet();\n        try {\n            super.run();\n        } finally {\n            alive.decrementAndGet();\n            if (debugLifecycle) {\n                logger.info(\"Thread \" + getName() + \" terminated\");\n            }\n        }\n    }\n    \n    public static int getCreatedCount() {\n        return created.get();\n    }\n    \n    public static int getAliveCount() {\n        return alive.get();\n    }\n    \n    public static void setDebug(boolean debug) {\n        debugLifecycle = debug;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        MyAppThread.setDebug(true);\n        \n        MyAppThread thread1 = new MyAppThread(() -> {\n            try {\n                Thread.sleep(1000);\n                System.out.println(\"Task 1 completed\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        MyAppThread thread2 = new MyAppThread(() -> {\n            try {\n                Thread.sleep(500);\n                System.out.println(\"Task 2 completed\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        MyAppThread thread3 = new MyAppThread(() -> {\n            System.out.println(\"Task 3 starting\");\n            throw new RuntimeException(\"Intentional error in task 3\");\n        });\n        \n        MyAppThread thread4 = new MyAppThread(() -> {\n            try {\n                Thread.sleep(750);\n                System.out.println(\"Task 4 completed\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        MyAppThread thread5 = new MyAppThread(() -> {\n            try {\n                Thread.sleep(250);\n                System.out.println(\"Task 5 completed\");\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        thread1.start();\n        thread2.start();\n        thread3.start();\n        thread4.start();\n        thread5.start();\n        \n        Thread.sleep(100);\n        System.out.println(\"Created threads: \" + MyAppThread.getCreatedCount());\n        System.out.println(\"Currently alive threads: \" + MyAppThread.getAliveCount());\n        \n        thread1.join();\n        thread2.join();\n        thread3.join();\n        thread4.join();\n        thread5.join();\n        \n        System.out.println(\"Final created threads: \" + MyAppThread.getCreatedCount());\n        System.out.println(\"Final alive threads: \" + MyAppThread.getAliveCount());\n    }\n}",
            "import java.util.concurrent.atomic.AtomicInteger;\nimport java.util.logging.Logger;\nimport java.util.logging.Level;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class MyAppThread extends Thread {\n    private static final String DEFAULT_NAME = \"MyAppThread\";\n    private static final AtomicInteger threadNumber = new AtomicInteger(0);\n    private static final Logger logger = Logger.getLogger(MyAppThread.class.getName());\n    private static volatile boolean debugLifecycle = false;\n    private static final AtomicInteger created = new AtomicInteger(0);\n    private static final AtomicInteger alive = new AtomicInteger(0);\n    \n    public MyAppThread() {\n        this(null);\n    }\n    \n    public MyAppThread(Runnable target) {\n        super(target, DEFAULT_NAME + \"-\" + threadNumber.incrementAndGet());\n        setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {\n            @Override\n            public void uncaughtException(Thread t, Throwable e) {\n                logger.log(Level.SEVERE, \"UNCAUGHT in thread \" + t.getName(), e);\n            }\n        });\n    }\n    \n    @Override\n    public void run() {\n        created.incrementAndGet();\n        if (debugLifecycle) {\n            logger.log(Level.INFO, \"Created \" + getName());\n        }\n        try {\n            alive.incrementAndGet();\n            super.run();\n        } finally {\n            alive.decrementAndGet();\n            if (debugLifecycle) {\n                logger.log(Level.INFO, \"Exiting \" + getName());\n            }\n        }\n    }\n    \n    public static int getCreated() {\n        return created.get();\n    }\n    \n    public static int getAlive() {\n        return alive.get();\n    }\n    \n    public static void setDebug(boolean debug) {\n        debugLifecycle = debug;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        MyAppThread.setDebug(true);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(3, r -> new MyAppThread(r));\n        \n        for (int i = 0; i < 5; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                System.out.println(\"Task \" + taskId + \" running on \" + Thread.currentThread().getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                if (taskId == 2) {\n                    throw new RuntimeException(\"Intentional error in task \" + taskId);\n                }\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"Total threads created: \" + MyAppThread.getCreated());\n        System.out.println(\"Currently alive threads: \" + MyAppThread.getAlive());\n    }\n}"
        ],
        "graded_list": [
            true,
            false,
            true
        ],
        "ground_truth": "import java.util.logging.Logger;\nimport java.util.logging.Level;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class MyAppThread extends Thread {\npublic static final String DEFAULT_NAME = \"MyAppThread\";\nprivate static volatile boolean debugLifecycle = false;\nprivate static final AtomicInteger created = new AtomicInteger();\nprivate static final AtomicInteger alive = new AtomicInteger();\nprivate static final Logger log = Logger.getAnonymousLogger();\n\npublic MyAppThread(Runnable r) {\nthis(r, DEFAULT_NAME);\n}\n\npublic MyAppThread(Runnable runnable, String name) {\nsuper(runnable, name + \"-\" + created.incrementAndGet());\nsetUncaughtExceptionHandler((t, e) -> {\nlog.log(Level.SEVERE,\n\"UNCAUGHT in thread \" + t.getName(), e);\n});\n}\n\n@Override\npublic void run() {\nboolean debug = debugLifecycle;\nif (debug) log.log(Level.FINE, \"Created \" + getName());\nalive.incrementAndGet();\ntry {\nsuper.run();\n} finally {\nalive.decrementAndGet();\nif (debug) log.log(Level.FINE, \"Exiting \" + getName());\n}\n}\n\npublic static int getThreadsCreated() {\nreturn created.get();\n}\n\npublic static int getThreadsAlive() {\nreturn alive.get();\n}\n\npublic static boolean getDebug() {\nreturn debugLifecycle;\n}\n\npublic static void setDebug(boolean b) {\ndebugLifecycle = b;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMyAppThread.setDebug(true);\n\nSystem.out.println(\"Starting test...\");\n\nfor (int i = 0; i < 5; i++) {\nRunnable task = () -> {\nSystem.out.println(Thread.currentThread().getName() + \" is running.\");\ntry {\nThread.sleep(1000);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\nSystem.err.println(\"Thread interrupted: \" + e.getMessage());\n}\nSystem.out.println(Thread.currentThread().getName() + \" is done.\");\n};\n\nMyAppThread thread = new MyAppThread(task, \"Worker\");\nthread.start();\n}\n\nwhile (MyAppThread.getThreadsAlive() > 0) {\nThread.sleep(100);\n}\n\nSystem.out.println(\"All threads have completed.\");\nSystem.out.println(\"Total threads created: \" + MyAppThread.getThreadsCreated());\nSystem.out.println(\"Currently alive threads: \" + MyAppThread.getThreadsAlive());\n}\n}",
        "max_depth": "120",
        "jpf_details": [
            "Unique logical threads created during execution: 8\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.22%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 73.65%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 70.61%)\n[JPF-STARVATION] Thread ID: 6 OK (waiting proportion: 73.90%)\n[JPF-STARVATION] Thread ID: 7 OK (waiting proportion: 4.65%)\n[JPF-STARVATION] Thread ID: 8 OK (waiting proportion: 12.36%)\n[JPF-STARVATION] Thread ID: 9 OK (waiting proportion: 3.93%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=75585,visited=78321,backtracked=152708,end=0\nsearch:             maxDepth=1200,constraints=53509\nchoice generators:  thread=38414 (signal=0,lock=1906,sharedRef=26935,threadApi=1933,reschedule=2594), data=0\nheap:               new=126717,released=58889,maxLive=1530,gcCycles=153700\ninstructions:       12891681\nmax memory:         1017MB\nloaded code:        classes=193,methods=3373\n\n====================================================== search finished",
            "at java.lang.String.format(String.java:2940)\n\tat gov.nasa.jpf.vm.MJIEnv.format(MJIEnv.java:1156)\n\tat gov.nasa.jpf.vm.JPF_java_lang_String.format__Ljava_lang_String_2_3Ljava_lang_Object_2__Ljava_lang_String_2(JPF_java_lang_String.java:595)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.vm.NativeMethodInfo.executeNative(NativeMethodInfo.java:125)\n\t... 15 more",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.34%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.35%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 74.35%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=73048,visited=80476,backtracked=152329,end=2\nsearch:             maxDepth=1200,constraints=47822\nchoice generators:  thread=39360 (signal=0,lock=5,sharedRef=32461,threadApi=1734,reschedule=57), data=0\nheap:               new=511593,released=500646,maxLive=1479,gcCycles=152629\ninstructions:       14116946\nmax memory:         1017MB\nloaded code:        classes=189,methods=3294\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMyAppThread.main()\n====================================================== search started: 11/17/25 3:18 PM\nCreated threads: 5\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.vm.NativeMethodInfo.executeNative(NativeMethodInfo.java:125)\n\t... 15 more",
            "no errors detected"
        ],
        "codebleu_score": [
            65.43,
            65.54,
            65.69
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Custom thread factory. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a custom ThreadFactory implementation called MyThreadFactory that generates instances of a specialized thread class named MyAppThread. The factory should take a poolName string as a constructor argument and use it to identify the thread group or pool. The newThread(Runnable runnable) method must return a new instance of MyAppThread, passing in the provided Runnable and the poolName.\nThe requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.*;\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        MyThreadFactory factory = new MyThreadFactory(\"MyPool\");\n        ExecutorService executor = Executors.newFixedThreadPool(5, factory);\n        \n        for (int i = 0; i < 10; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                System.out.println(\"Task \" + taskId + \" running on \" + Thread.currentThread().getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n\nclass MyThreadFactory implements ThreadFactory {\n    private final String poolName;\n    private int threadNumber = 0;\n    \n    public MyThreadFactory(String poolName) {\n        this.poolName = poolName;\n    }\n    \n    public Thread newThread(Runnable runnable) {\n        threadNumber++;\n        return new MyAppThread(runnable, poolName + \"-Thread-\" + threadNumber);\n    }\n}\n\nclass MyAppThread extends Thread {\n    private final String poolName;\n    \n    public MyAppThread(Runnable runnable, String poolName) {\n        super(runnable);\n        this.poolName = poolName;\n        setName(poolName);\n    }\n    \n    public String getPoolName() {\n        return poolName;\n    }\n}",
            "import java.util.concurrent.*;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        MyThreadFactory factory = new MyThreadFactory(\"WorkerPool\");\n        ExecutorService executor = Executors.newFixedThreadPool(5, factory);\n        \n        CountDownLatch latch = new CountDownLatch(10);\n        \n        for (int i = 0; i < 10; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                try {\n                    System.out.println(\"Task \" + taskId + \" executing on \" + Thread.currentThread().getName());\n                    Thread.sleep(100);\n                    System.out.println(\"Task \" + taskId + \" completed\");\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                } finally {\n                    latch.countDown();\n                }\n            });\n        }\n        \n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n\nclass MyThreadFactory implements ThreadFactory {\n    private final String poolName;\n    private final AtomicInteger threadNumber = new AtomicInteger(1);\n    \n    public MyThreadFactory(String poolName) {\n        this.poolName = poolName;\n    }\n    \n    @Override\n    public Thread newThread(Runnable runnable) {\n        return new MyAppThread(runnable, poolName);\n    }\n}\n\nclass MyAppThread extends Thread {\n    private static final AtomicInteger globalThreadNumber = new AtomicInteger(1);\n    private final String poolName;\n    \n    public MyAppThread(Runnable runnable, String poolName) {\n        super(runnable);\n        this.poolName = poolName;\n        setName(poolName + \"-Thread-\" + globalThreadNumber.getAndIncrement());\n    }\n}",
            "import java.util.concurrent.*;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        MyThreadFactory factory = new MyThreadFactory(\"MyPool\");\n        ExecutorService executor = Executors.newFixedThreadPool(3, factory);\n        \n        CountDownLatch latch = new CountDownLatch(5);\n        \n        for (int i = 0; i < 5; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                System.out.println(\"Task \" + taskId + \" running on \" + Thread.currentThread().getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                latch.countDown();\n            });\n        }\n        \n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n\nclass MyThreadFactory implements ThreadFactory {\n    private final String poolName;\n    private final AtomicInteger threadNumber = new AtomicInteger(1);\n    \n    public MyThreadFactory(String poolName) {\n        this.poolName = poolName;\n    }\n    \n    public Thread newThread(Runnable runnable) {\n        return new MyAppThread(runnable, poolName);\n    }\n}\n\nclass MyAppThread extends Thread {\n    private static final AtomicInteger globalThreadNumber = new AtomicInteger(1);\n    private final String poolName;\n    \n    public MyAppThread(Runnable runnable, String poolName) {\n        super(runnable);\n        this.poolName = poolName;\n        setName(poolName + \"-Thread-\" + globalThreadNumber.getAndIncrement());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "interface ThreadFactory {\nThread newThread(Runnable r);\n}\n\nclass MyThreadFactory implements ThreadFactory {\nprivate final String poolName;\n\npublic MyThreadFactory(String poolName) {\nthis.poolName = poolName;\n}\n\n@Override\npublic Thread newThread(Runnable runnable) {\nreturn new MyAppThread(runnable, poolName);\n}\n}\n\nclass MyAppThread extends Thread {\nprivate static int counter = 0;\n\npublic MyAppThread(Runnable target, String threadPoolName) {\nsuper(target, threadPoolName + \"-thread-\" + nextId());\nsetDaemon(false);\nsetUncaughtExceptionHandler((t, e) -> {\nSystem.err.println(\"Exception in \" + t.getName() + \": \" + e.getMessage());\n});\n}\n\nprivate static synchronized int nextId() {\nreturn counter++;\n}\n}\n\npublic class CustomThreadPoolTest {\npublic static void main(String[] args) {\nThreadFactory factory = new MyThreadFactory(\"WorkerPool\");\n\nfor (int i = 0; i < 5; i++) {\nThread thread = factory.newThread(() -> {\nSystem.out.println(Thread.currentThread().getName() + \" is running\");\ntry {\nThread.sleep(1000);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\nSystem.err.println(\"Thread interrupted: \" + e.getMessage());\n}\n});\nthread.start();\n}\n}\n}",
        "max_depth": "22",
        "jpf_details": [
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 83.08%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 83.08%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 83.08%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 83.08%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 83.08%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=104087,visited=153874,backtracked=257741,end=0\nsearch:             maxDepth=220,constraints=117660\nchoice generators:  thread=43625 (signal=0,lock=11,sharedRef=38953,threadApi=1129,reschedule=255), data=0\nheap:               new=81480,released=202274,maxLive=767,gcCycles=257961\ninstructions:       20334919\nmax memory:         1019MB\nloaded code:        classes=137,methods=2408\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.09%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 34.66%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 37.47%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 37.60%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 32.38%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 70.28%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=102391,visited=57432,backtracked=159604,end=827\nsearch:             maxDepth=220,constraints=70048\nchoice generators:  thread=45037 (signal=0,lock=11,sharedRef=19751,threadApi=14,reschedule=14934), data=0\nheap:               new=307204,released=891161,maxLive=770,gcCycles=159823\ninstructions:       97145910\nmax memory:         1016MB\nloaded code:        classes=143,methods=2451\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 14.50%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 27.93%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 30.15%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 59.58%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=146990,visited=38125,backtracked=184896,end=7801\nsearch:             maxDepth=220,constraints=83153\nchoice generators:  thread=73635 (signal=0,lock=7,sharedRef=20352,threadApi=7,reschedule=28342), data=0\nheap:               new=404510,released=1063217,maxLive=744,gcCycles=185115\ninstructions:       87229425\nmax memory:         1018MB\nloaded code:        classes=143,methods=2451\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            45.97,
            58.01,
            57.31
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Delegating thread safety to a ConcurrentHashMap. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called DelegatingVehicleTracker that manages the locations of vehicles in a thread-safe manner. The class should use a ConcurrentHashMap to store vehicle locations, where each vehicle is identified by a unique String ID and its current location is represented by a Point object. Provide the following functionality:\n\nA constructor that accepts an initial Map of vehicle IDs to Points and initializes the internal concurrent map with these values.\nA method getLocations() that returns an unmodifiable view of the current vehicle locations to prevent external modification.\nA method getLocation(String id) that returns the current location of the specified vehicle or null if the vehicle does not exist.\nA method setLocation(String id, int x, int y) that updates the location of an existing vehicle with the given ID to the new coordinates (x, y). If the vehicle does not exist, this method should throw an appropriate exception such as IllegalArgumentException.\nAn alternative method getLocationsAsStatic() that returns a snapshot of the current locations as an unmodifiable Map to provide a consistent view of all locations at the time of invocation.\nEnsure that all operations are thread-safe without requiring additional synchronization in the class. Use standard Java libraries for concurrency and collections. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Point {\n  private final int x;\n  private final int y;\n\n  public Point(int x, int y) {\n    this.x = x;\n    this.y = y;\n  }\n\n  public int getX() {\n    return x;\n  }\n\n  public int getY() {\n    return y;\n  }\n\n  public String toString() {\n    return \"(\" + x + \", \" + y + \")\";\n  }\n\n  public boolean equals(Object obj) {\n    if (this == obj) return true;\n    if (obj == null || getClass() != obj.getClass()) return false;\n    Point point = (Point) obj;\n    return x == point.x && y == point.y;\n  }\n\n  public int hashCode() {\n    return Objects.hash(x, y);\n  }\n}\n\nclass DelegatingVehicleTracker {\n  private final ConcurrentHashMap<String, Point> locations;\n\n  public DelegatingVehicleTracker(Map<String, Point> points) {\n    this.locations = new ConcurrentHashMap<>(points);\n  }\n\n  public Map<String, Point> getLocations() {\n    return Collections.unmodifiableMap(locations);\n  }\n\n  public Point getLocation(String id) {\n    return locations.get(id);\n  }\n\n  public void setLocation(String id, int x, int y) {\n    Point existingPoint = locations.get(id);\n    if (existingPoint == null) {\n      throw new IllegalArgumentException(\"Vehicle with ID \" + id + \" does not exist\");\n    }\n    locations.put(id, new Point(x, y));\n  }\n\n  public Map<String, Point> getLocationsAsStatic() {\n    return Collections.unmodifiableMap(new HashMap<>(locations));\n  }\n}\n\npublic class VehicleTrackerDemo {\n  public static void main(String[] args) {\n    Map<String, Point> initialLocations = new HashMap<>();\n    initialLocations.put(\"vehicle1\", new Point(10, 20));\n    initialLocations.put(\"vehicle2\", new Point(30, 40));\n\n    DelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n\n    Thread thread1 = new Thread(() -> {\n      try {\n        tracker.setLocation(\"vehicle1\", 15, 25);\n        Point loc = tracker.getLocation(\"vehicle1\");\n        if (loc != null) {\n          System.out.println(\"Thread1: \" + loc);\n        }\n      } catch (Exception e) {\n        System.out.println(\"Thread1 error: \" + e.getMessage());\n      }\n    });\n\n    Thread thread2 = new Thread(() -> {\n      try {\n        tracker.setLocation(\"vehicle2\", 35, 45);\n        Point loc = tracker.getLocation(\"vehicle2\");\n        if (loc != null) {\n          System.out.println(\"Thread2: \" + loc);\n        }\n      } catch (Exception e) {\n        System.out.println(\"Thread2 error: \" + e.getMessage());\n      }\n    });\n\n    thread1.start();\n    thread2.start();\n\n    try {\n      thread1.join();\n      thread2.join();\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n\n    Map<String, Point> finalLocations = tracker.getLocations();\n    System.out.println(\"Final locations: \" + finalLocations);\n\n    Map<String, Point> snapshot = tracker.getLocationsAsStatic();\n    System.out.println(\"Snapshot: \" + snapshot);\n\n    try {\n      tracker.setLocation(\"nonexistent\", 0, 0);\n    } catch (IllegalArgumentException e) {\n      System.out.println(\"Expected exception: \" + e.getMessage());\n    }\n  }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Point {\n    public final int x;\n    public final int y;\n    \n    public Point(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Point{x=\" + x + \", y=\" + y + \"}\";\n    }\n}\n\nclass DelegatingVehicleTracker {\n    private final ConcurrentHashMap<String, Point> locations;\n    \n    public DelegatingVehicleTracker(Map<String, Point> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n    }\n    \n    public Map<String, Point> getLocations() {\n        return Collections.unmodifiableMap(locations);\n    }\n    \n    public Point getLocation(String id) {\n        return locations.get(id);\n    }\n    \n    public void setLocation(String id, int x, int y) {\n        if (locations.replace(id, new Point(x, y)) == null) {\n            throw new IllegalArgumentException(\"Vehicle with ID \" + id + \" does not exist\");\n        }\n    }\n    \n    public Map<String, Point> getLocationsAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(locations));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, Point> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new Point(0, 0));\n        initialLocations.put(\"vehicle2\", new Point(10, 10));\n        initialLocations.put(\"vehicle3\", new Point(20, 20));\n        initialLocations.put(\"vehicle4\", new Point(30, 30));\n        initialLocations.put(\"vehicle5\", new Point(40, 40));\n        \n        DelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 2);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                tracker.setLocation(\"vehicle2\", i * 3, i * 3);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Point location = tracker.getLocation(\"vehicle1\");\n                if (location != null) {\n                    System.out.println(\"Vehicle1 at: \" + location);\n                }\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, Point> snapshot = tracker.getLocationsAsStatic();\n                System.out.println(\"Snapshot \" + i + \": \" + snapshot.size() + \" vehicles\");\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                tracker.setLocation(\"vehicle3\", i * 5, i * 5);\n                tracker.setLocation(\"vehicle4\", i * 4, i * 4);\n                try {\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final locations:\");\n        Map<String, Point> finalLocations = tracker.getLocations();\n        for (Map.Entry<String, Point> entry : finalLocations.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass Point {\n    public final int x;\n    public final int y;\n    \n    public Point(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Point(\" + x + \", \" + y + \")\";\n    }\n}\n\nclass DelegatingVehicleTracker {\n    private final ConcurrentHashMap<String, Point> locations;\n    \n    public DelegatingVehicleTracker(Map<String, Point> points) {\n        locations = new ConcurrentHashMap<>(points);\n    }\n    \n    public Map<String, Point> getLocations() {\n        return Collections.unmodifiableMap(locations);\n    }\n    \n    public Point getLocation(String id) {\n        return locations.get(id);\n    }\n    \n    public void setLocation(String id, int x, int y) {\n        if (!locations.containsKey(id)) {\n            throw new IllegalArgumentException(\"Vehicle with ID \" + id + \" does not exist\");\n        }\n        locations.put(id, new Point(x, y));\n    }\n    \n    public Map<String, Point> getLocationsAsStatic() {\n        return Collections.unmodifiableMap(new HashMap<>(locations));\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, Point> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new Point(10, 20));\n        initialLocations.put(\"vehicle2\", new Point(30, 40));\n        initialLocations.put(\"vehicle3\", new Point(50, 60));\n        initialLocations.put(\"vehicle4\", new Point(70, 80));\n        \n        DelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    tracker.setLocation(\"vehicle2\", i * 15, i * 25);\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                try {\n                    Point location = tracker.getLocation(\"vehicle1\");\n                    System.out.println(\"Vehicle1 location: \" + location);\n                    Thread.sleep(60);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    Map<String, Point> snapshot = tracker.getLocationsAsStatic();\n                    System.out.println(\"Snapshot: \" + snapshot);\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        futures.add(executor.submit(() -> {\n            for (int i = 0; i < 8; i++) {\n                try {\n                    tracker.setLocation(\"vehicle3\", i * 5, i * 10);\n                    tracker.setLocation(\"vehicle4\", i * 7, i * 14);\n                    Thread.sleep(70);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final locations: \" + tracker.getLocations());\n    }\n}"
        ],
        "graded_list": [
            true,
            false,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.awt.Point;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.concurrent.ConcurrentMap;\nimport java.util.Collections;\n\n/**\n* DelegatingVehicleTracker\n* Tracks vehicle locations using a thread-safe ConcurrentHashMap.\n* Modified to use explicit Threads for JPF compatibility.\n*/\npublic class DelegatingVehicleTracker {\nprivate final ConcurrentMap<String, Point> locations;\nprivate final Map<String, Point> unmodifiableMap;\n\npublic DelegatingVehicleTracker(Map<String, Point> points) {\nlocations = new ConcurrentHashMap<>(points);\nunmodifiableMap = Collections.unmodifiableMap(locations);\n}\n\npublic Map<String, Point> getLocations() {\nreturn unmodifiableMap;\n}\n\npublic Point getLocation(String id) {\nreturn locations.get(id);\n}\n\npublic void setLocation(String id, int x, int y) {\nif (locations.replace(id, new Point(x, y)) == null)\nthrow new IllegalArgumentException(\"Invalid vehicle ID: \" + id);\n}\n\npublic Map<String, Point> getLocationsAsStatic() {\nreturn Collections.unmodifiableMap(new HashMap<>(locations));\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, Point> initialLocations = new HashMap<>();\ninitialLocations.put(\"V1\", new Point(0, 0));\ninitialLocations.put(\"V2\", new Point(10, 10));\ninitialLocations.put(\"V3\", new Point(20, 20));\n\nDelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n\n// Reduce thread count and iterations to shorten JPF testing time\nThread[] threads = new Thread[2]; // fewer threads\n\nfor (int i = 0; i < 2; i++) {\nfinal int threadId = i;\nthreads[i] = new Thread(() -> {\nRandom rand = new Random();\nfor (int j = 0; j < 3; j++) { // fewer iterations\nString vehicleId = \"V\" + ((threadId % 3) + 1);\nint newX = rand.nextInt(21); // 0 to 20\nint newY = rand.nextInt(21); // 0 to 20\nSystem.out.println(\"Thread-\" + threadId + \": Setting \" + vehicleId + \" to (\" + newX + \", \" + newY + \")\");\ntracker.setLocation(vehicleId, newX, newY);\ntry {\nThread.sleep(20); // shorter sleep to speed up execution\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\nfor (Map.Entry<String, Point> entry : tracker.getLocations().entrySet()) {\nSystem.out.println(entry.getKey() + \" => \" + entry.getValue());\n}\n}\n}",
        "max_depth": "81",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 48.89%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 31.11%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.11%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=25,visited=20,backtracked=45,end=3\nsearch:             maxDepth=8,constraints=0\nchoice generators:  thread=25 (signal=0,lock=1,sharedRef=9,threadApi=5,reschedule=10), data=0\nheap:               new=1252,released=481,maxLive=611,gcCycles=33\ninstructions:       20213\nmax memory:         981MB\nloaded code:        classes=113,methods=2178\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 2.70%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 16.22%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\"\n\n====================================================== statistics\nstates:             new=37,visited=0,backtracked=0,end=0\nsearch:             maxDepth=37,constraints=0\nchoice generators:  thread=37 (signal=0,lock=7,sharedRef=24,threadApi=5,reschedule=0), data=0\nheap:               new=949,released=60,maxLive=877,gcCycles=35\ninstructions:       13744\nmax memory:         981MB\nloaded code:        classes=152,methods=2828\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 2.70%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 16.22%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\"\n\n====================================================== statistics\nstates:             new=37,visited=0,backtracked=0,end=0\nsearch:             maxDepth=37,constraints=0\nchoice generators:  thread=37 (signal=0,lock=7,sharedRef=24,threadApi=5,reschedule=0), data=0\nheap:               new=944,released=60,maxLive=872,gcCycles=35\ninstructions:       13427\nmax memory:         981MB\nloaded code:        classes=153,methods=2830\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\""
        ],
        "codebleu_score": [
            56.1,
            61.58,
            57.95
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Driver loop that induces deadlock under typical conditions. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class named DemonstrateDeadlock that simulates concurrent money transfers between multiple accounts to demonstrate the possibility of deadlock in multithreaded applications. The program should create a fixed number of threads (e.g., 20) and a fixed number of account objects (e.g., 5). Each thread performs a large number of random transfers (e.g., 1,000,000 iterations), selecting two random accounts and transferring a random amount using a method from a class called DynamicOrderDeadlock.transferMoney(Account from, Account to, DollarAmount amount). This method is expected to lock both accounts before performing the transfer and may throw an InsufficientFundsException, which should be caught and ignored. Each account is initialized with a default value and must be thread-safe or synchronized as needed. Use a nested static class TransferThread that extends Thread and implements the transfer logic. Use Random to generate random indices for accounts and amounts. \nThe requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.Random;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class DemonstrateDeadlock {\n    \n    private static final int NUM_ACCOUNTS = 5;\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Account[] accounts = new Account[NUM_ACCOUNTS];\n    \n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_ACCOUNTS; i++) {\n            accounts[i] = new Account(new DollarAmount(1000));\n        }\n        \n        Thread[] threads = new Thread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new TransferThread();\n            threads[i].start();\n        }\n        \n        for (Thread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    static class TransferThread extends Thread {\n        private final Random random = new Random();\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_ACCOUNTS);\n                int toIndex = random.nextInt(NUM_ACCOUNTS);\n                while (fromIndex == toIndex) {\n                    toIndex = random.nextInt(NUM_ACCOUNTS);\n                }\n                \n                DollarAmount amount = new DollarAmount(random.nextInt(100) + 1);\n                \n                try {\n                    DynamicOrderDeadlock.transferMoney(accounts[fromIndex], accounts[toIndex], amount);\n                } catch (InsufficientFundsException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Account {\n    private final Lock lock = new ReentrantLock();\n    private DollarAmount balance;\n    \n    public Account(DollarAmount initialBalance) {\n        this.balance = initialBalance;\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n    \n    public void debit(DollarAmount amount) throws InsufficientFundsException {\n        if (balance.compareTo(amount) < 0) {\n            throw new InsufficientFundsException();\n        }\n        balance = balance.subtract(amount);\n    }\n    \n    public void credit(DollarAmount amount) {\n        balance = balance.add(amount);\n    }\n    \n    public DollarAmount getBalance() {\n        return balance;\n    }\n}\n\nclass DollarAmount {\n    private final int cents;\n    \n    public DollarAmount(int dollars) {\n        this.cents = dollars * 100;\n    }\n    \n    private DollarAmount(int cents, boolean isCents) {\n        this.cents = cents;\n    }\n    \n    public DollarAmount add(DollarAmount other) {\n        return new DollarAmount(this.cents + other.cents, true);\n    }\n    \n    public DollarAmount subtract(DollarAmount other) {\n        return new DollarAmount(this.cents - other.cents, true);\n    }\n    \n    public int compareTo(DollarAmount other) {\n        return Integer.compare(this.cents, other.cents);\n    }\n}\n\nclass DynamicOrderDeadlock {\n    public static void transferMoney(Account from, Account to, DollarAmount amount) \n            throws InsufficientFundsException {\n        from.getLock().lock();\n        try {\n            to.getLock().lock();\n            try {\n                from.debit(amount);\n                to.credit(amount);\n            } finally {\n                to.getLock().unlock();\n            }\n        } finally {\n            from.getLock().unlock();\n        }\n    }\n}\n\nclass InsufficientFundsException extends Exception {\n    public InsufficientFundsException() {\n        super();\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class DemonstrateDeadlock {\n    private static final int NUM_ACCOUNTS = 5;\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ITERATIONS = 10;\n    private static final Account[] accounts = new Account[NUM_ACCOUNTS];\n\n    public static void main(String[] args) {\n        for (int i = 0; i < NUM_ACCOUNTS; i++) {\n            accounts[i] = new Account(1000);\n        }\n\n        Thread[] threads = new Thread[NUM_THREADS];\n        for (int i = 0; i < NUM_THREADS; i++) {\n            threads[i] = new TransferThread();\n            threads[i].start();\n        }\n\n        for (Thread thread : threads) {\n            try {\n                thread.join();\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n\n    static class TransferThread extends Thread {\n        private final Random random = new Random();\n\n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(NUM_ACCOUNTS);\n                int toIndex = random.nextInt(NUM_ACCOUNTS);\n                while (fromIndex == toIndex) {\n                    toIndex = random.nextInt(NUM_ACCOUNTS);\n                }\n                \n                DollarAmount amount = new DollarAmount(random.nextInt(100) + 1);\n                \n                try {\n                    DynamicOrderDeadlock.transferMoney(accounts[fromIndex], accounts[toIndex], amount);\n                } catch (InsufficientFundsException e) {\n                }\n            }\n        }\n    }\n}\n\nclass Account {\n    private final Lock lock = new ReentrantLock();\n    private int balance;\n\n    public Account(int initialBalance) {\n        this.balance = initialBalance;\n    }\n\n    public void debit(DollarAmount amount) throws InsufficientFundsException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientFundsException();\n        }\n        balance -= amount.getAmount();\n    }\n\n    public void credit(DollarAmount amount) {\n        balance += amount.getAmount();\n    }\n\n    public int getBalance() {\n        return balance;\n    }\n\n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass DollarAmount {\n    private final int amount;\n\n    public DollarAmount(int amount) {\n        this.amount = amount;\n    }\n\n    public int getAmount() {\n        return amount;\n    }\n}\n\nclass InsufficientFundsException extends Exception {\n    public InsufficientFundsException() {\n        super();\n    }\n}\n\nclass DynamicOrderDeadlock {\n    public static void transferMoney(Account from, Account to, DollarAmount amount) \n            throws InsufficientFundsException {\n        from.getLock().lock();\n        try {\n            to.getLock().lock();\n            try {\n                from.debit(amount);\n                to.credit(amount);\n            } finally {\n                to.getLock().unlock();\n            }\n        } finally {\n            from.getLock().unlock();\n        }\n    }\n}",
            "import java.util.Random;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class DemonstrateDeadlock {\n    private static final int NUM_ACCOUNTS = 5;\n    private static final int NUM_THREADS = 2;\n    private static final int NUM_ITERATIONS = 1000000;\n    \n    public static void main(String[] args) throws InterruptedException {\n        Account[] accounts = new Account[NUM_ACCOUNTS];\n        for (int i = 0; i < NUM_ACCOUNTS; i++) {\n            accounts[i] = new Account(new DollarAmount(1000));\n        }\n        \n        ExecutorService executor = Executors.newFixedThreadPool(NUM_THREADS);\n        \n        for (int i = 0; i < NUM_THREADS; i++) {\n            executor.submit(new TransferThread(accounts));\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(60, TimeUnit.SECONDS);\n    }\n    \n    static class TransferThread extends Thread {\n        private final Account[] accounts;\n        private final Random random = new Random();\n        \n        TransferThread(Account[] accounts) {\n            this.accounts = accounts;\n        }\n        \n        @Override\n        public void run() {\n            for (int i = 0; i < NUM_ITERATIONS; i++) {\n                int fromIndex = random.nextInt(accounts.length);\n                int toIndex = random.nextInt(accounts.length);\n                \n                if (fromIndex != toIndex) {\n                    DollarAmount amount = new DollarAmount(random.nextInt(100) + 1);\n                    try {\n                        DynamicOrderDeadlock.transferMoney(accounts[fromIndex], accounts[toIndex], amount);\n                    } catch (InsufficientFundsException e) {\n                    }\n                }\n            }\n        }\n    }\n}\n\nclass Account {\n    private DollarAmount balance;\n    \n    Account(DollarAmount initialBalance) {\n        this.balance = initialBalance;\n    }\n    \n    synchronized void debit(DollarAmount amount) throws InsufficientFundsException {\n        if (balance.compareTo(amount) < 0) {\n            throw new InsufficientFundsException();\n        }\n        balance = balance.subtract(amount);\n    }\n    \n    synchronized void credit(DollarAmount amount) {\n        balance = balance.add(amount);\n    }\n    \n    synchronized DollarAmount getBalance() {\n        return balance;\n    }\n}\n\nclass DollarAmount {\n    private final int cents;\n    \n    DollarAmount(int dollars) {\n        this.cents = dollars * 100;\n    }\n    \n    private DollarAmount(int cents, boolean internal) {\n        this.cents = cents;\n    }\n    \n    DollarAmount add(DollarAmount other) {\n        return new DollarAmount(this.cents + other.cents, true);\n    }\n    \n    DollarAmount subtract(DollarAmount other) {\n        return new DollarAmount(this.cents - other.cents, true);\n    }\n    \n    int compareTo(DollarAmount other) {\n        return Integer.compare(this.cents, other.cents);\n    }\n}\n\nclass DynamicOrderDeadlock {\n    static void transferMoney(Account from, Account to, DollarAmount amount) throws InsufficientFundsException {\n        synchronized (from) {\n            synchronized (to) {\n                from.debit(amount);\n                to.credit(amount);\n            }\n        }\n    }\n}\n\nclass InsufficientFundsException extends Exception {\n    InsufficientFundsException() {\n        super();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.Random;\n\npublic class DemonstrateDeadlock {\nprivate static final int NUM_THREADS = 2;\nprivate static final int NUM_ACCOUNTS = 2;\nprivate static final int NUM_ITERATIONS = 10;\n\npublic static void main(String[] args) {\nfinal Random rnd = new Random();\nfinal Account[] accounts = new Account[NUM_ACCOUNTS];\n\nfor (int i = 0; i < accounts.length; i++)\naccounts[i] = new Account();\n\nclass TransferThread extends Thread {\npublic void run() {\nfor (int i = 0; i < NUM_ITERATIONS; i++) {\nint fromAcct = rnd.nextInt(NUM_ACCOUNTS);\nint toAcct = rnd.nextInt(NUM_ACCOUNTS);\nif (fromAcct == toAcct)\ncontinue;\nDollarAmount amount = new DollarAmount(rnd.nextInt(1000));\ntry {\nDynamicOrderDeadlock.transferMoney(accounts[fromAcct], accounts[toAcct], amount);\n} catch (DynamicOrderDeadlock.InsufficientFundsException ignored) {\n}\n}\n}\n}\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nnew TransferThread().start();\n}\n}\n}\n\nclass Account {\nprivate volatile int balance;\n\npublic Account() {\nthis.balance = 1000;\n}\n\npublic synchronized int getBalance() {\nreturn balance;\n}\n\npublic synchronized void setBalance(int balance) {\nthis.balance = balance;\n}\n}\n\nclass DollarAmount {\nprivate final int value;\n\npublic DollarAmount(int value) {\nthis.value = value;\n}\n\npublic int getValue() {\nreturn value;\n}\n}\n\nclass DynamicOrderDeadlock {\npublic static void transferMoney(Account fromAcct, Account toAcct, DollarAmount amount)\nthrows InsufficientFundsException {\nAccount first = fromAcct;\nAccount second = toAcct;\nif (System.identityHashCode(first) > System.identityHashCode(second)) {\nfirst = toAcct;\nsecond = fromAcct;\n}\n\nsynchronized (first) {\nsynchronized (second) {\nif (fromAcct.getBalance() < amount.getValue())\nthrow new InsufficientFundsException();\nfromAcct.setBalance(fromAcct.getBalance() - amount.getValue());\ntoAcct.setBalance(toAcct.getBalance() + amount.getValue());\n}\n}\n}\n\npublic static class InsufficientFundsException extends Exception {}\n}",
        "max_depth": "30",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.40%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.14%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.28%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=243785,visited=225091,backtracked=468815,end=80\nsearch:             maxDepth=233,constraints=0\nchoice generators:  thread=243746 (signal=0,lock=4407,sharedRef=162115,threadApi=5377,reschedule=59905), data=0\nheap:               new=323724,released=238541,maxLive=565,gcCycles=414140\ninstructions:       33920123\nmax memory:         1020MB\nloaded code:        classes=99,methods=2006\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 3.29%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 48.23%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.33%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=240118,visited=222584,backtracked=462553,end=84\nsearch:             maxDepth=193,constraints=0\nchoice generators:  thread=240076 (signal=0,lock=4127,sharedRef=155303,threadApi=4784,reschedule=64920), data=0\nheap:               new=205638,released=116824,maxLive=560,gcCycles=462702\ninstructions:       33046367\nmax memory:         1021MB\nloaded code:        classes=99,methods=2003\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.60%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 66.60%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=263210,visited=38351,backtracked=301262,end=0\nsearch:             maxDepth=300,constraints=186201\nchoice generators:  thread=100716 (signal=0,lock=979,sharedRef=53310,threadApi=2,reschedule=7784), data=0\nheap:               new=33664,released=32,maxLive=753,gcCycles=301561\ninstructions:       11436474\nmax memory:         1019MB\nloaded code:        classes=139,methods=2412\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            50.68,
            52.85,
            52.74
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Eager initialization. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that demonstrates eager initialization of a singleton resource. The program should include a class with a static instance of the resource that is created at the time of class loading. Provide a static method to retrieve this instance. The resource class should have a simple method (e.g., doSomething) that outputs a message to the console. In the main method, create and start multiple threads that access the shared resource and invoke the doSomething method. Ensure all threads complete before printing a final message indicating completion The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EagerSingletonDemo {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                SingletonResource resource = SingletonResource.getInstance();\n                resource.doSomething(\"Thread-\" + threadId);\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"All threads completed successfully\");\n    }\n}\n\nclass SingletonResource {\n    private static final SingletonResource INSTANCE = new SingletonResource();\n    \n    private SingletonResource() {\n        System.out.println(\"SingletonResource initialized\");\n    }\n    \n    public static SingletonResource getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void doSomething(String caller) {\n        System.out.println(\"Executing doSomething() from \" + caller);\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        System.out.println(\"Completed doSomething() for \" + caller);\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EagerSingletonDemo {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                Resource resource = Resource.getInstance();\n                resource.doSomething(\"Thread-\" + threadId);\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"All threads completed successfully\");\n    }\n}\n\nclass Resource {\n    private static final Resource INSTANCE = new Resource();\n    \n    private Resource() {\n        System.out.println(\"Resource initialized\");\n    }\n    \n    public static Resource getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void doSomething(String caller) {\n        System.out.println(\"Doing something for \" + caller);\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class EagerSingletonDemo {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 3; i++) {\n            final int threadId = i + 1;\n            executor.submit(() -> {\n                SingletonResource resource = SingletonResource.getInstance();\n                resource.doSomething(\"Thread-\" + threadId);\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"All threads completed successfully\");\n    }\n}\n\nclass SingletonResource {\n    private static final SingletonResource INSTANCE = new SingletonResource();\n    \n    private SingletonResource() {\n        System.out.println(\"SingletonResource initialized\");\n    }\n    \n    public static SingletonResource getInstance() {\n        return INSTANCE;\n    }\n    \n    public synchronized void doSomething(String caller) {\n        System.out.println(\"Executing doSomething() from \" + caller);\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        System.out.println(\"Completed doSomething() for \" + caller);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class EagerInitialization {\nprivate static final Resource resource = new Resource();\n\npublic static Resource getResource() {\nreturn resource;\n}\n\nstatic class Resource {\npublic void doSomething() {\nSystem.out.println(Thread.currentThread().getName() + \": Resource is doing something.\");\n}\n}\n\npublic static void main(String[] args) {\nRunnable task = () -> {\nResource res = getResource();\nres.doSomething();\n};\n\nThread t1 = new Thread(task, \"Thread-1\");\nThread t2 = new Thread(task, \"Thread-2\");\nThread t3 = new Thread(task, \"Thread-3\");\n\nt1.start();\nt2.start();\nt3.start();\n\ntry {\nt1.join();\nt2.join();\nt3.join();\n} catch (InterruptedException e) {\ne.printStackTrace();\n}\n\nSystem.out.println(\"All threads completed.\");\n}\n}",
        "max_depth": "46",
        "jpf_details": [
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.54%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.56%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.57%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=177596,visited=102919,backtracked=280055,end=1\nsearch:             maxDepth=460,constraints=141329\nchoice generators:  thread=70782 (signal=0,lock=2710,sharedRef=51340,threadApi=1201,reschedule=452), data=0\nheap:               new=162172,released=199007,maxLive=740,gcCycles=279486\ninstructions:       17031939\nmax memory:         1020MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.29%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.36%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.38%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=137707,visited=157931,backtracked=295178,end=1\nsearch:             maxDepth=460,constraints=89987\nchoice generators:  thread=74738 (signal=0,lock=5274,sharedRef=60543,threadApi=3,reschedule=1283), data=0\nheap:               new=301732,released=429583,maxLive=740,gcCycles=292263\ninstructions:       25069979\nmax memory:         1019MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.10%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.16%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.17%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=136493,visited=155082,backtracked=291127,end=0\nsearch:             maxDepth=460,constraints=89177\nchoice generators:  thread=73763 (signal=0,lock=5161,sharedRef=57231,threadApi=2733,reschedule=1052), data=0\nheap:               new=335094,released=440801,maxLive=742,gcCycles=288227\ninstructions:       24538297\nmax memory:         1019MB\nloaded code:        classes=137,methods=2411\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            54.36,
            52.81,
            54.36
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Generating a second's worth of prime numbers. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that generates prime numbers in a separate thread for a duration of one second and then cancels the generation process. The program should use a volatile variable to manage the cancellation state, store the generated prime numbers in a thread-safe list, and provide a method to retrieve the collected primes. Generate up to 10 prime numbers. Use an ExecutorService to manage the thread execution. The PrimeGenerator class should implement Runnable, include methods to start and cancel the generation, and ensure proper synchronization when accessing shared data. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.ArrayList;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PrimeGeneratorProgram {\n    public static void main(String[] args) throws InterruptedException {\n        PrimeGenerator generator = new PrimeGenerator();\n        ExecutorService executor = Executors.newSingleThreadExecutor();\n        \n        executor.submit(generator);\n        Thread.sleep(1000);\n        generator.cancel();\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        List<Integer> primes = generator.getPrimes();\n        System.out.println(\"Generated primes: \" + primes);\n    }\n}\n\nclass PrimeGenerator implements Runnable {\n    private volatile boolean cancelled = false;\n    private final List<Integer> primes = Collections.synchronizedList(new ArrayList<>());\n    private static final int MAX_PRIMES = 10;\n    \n    @Override\n    public void run() {\n        int number = 2;\n        while (!cancelled && primes.size() < MAX_PRIMES) {\n            if (isPrime(number)) {\n                primes.add(number);\n            }\n            number++;\n        }\n    }\n    \n    private boolean isPrime(int n) {\n        if (n <= 1) return false;\n        if (n <= 3) return true;\n        if (n % 2 == 0 || n % 3 == 0) return false;\n        for (int i = 5; i * i <= n; i += 6) {\n            if (n % i == 0 || n % (i + 2) == 0) return false;\n        }\n        return true;\n    }\n    \n    public void cancel() {\n        cancelled = true;\n    }\n    \n    public List<Integer> getPrimes() {\n        synchronized (primes) {\n            return new ArrayList<>(primes);\n        }\n    }\n}",
            "import java.util.ArrayList;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PrimeGeneratorProgram {\n    public static void main(String[] args) {\n        PrimeGenerator generator = new PrimeGenerator();\n        generator.start();\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        generator.cancel();\n        \n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        List<Integer> primes = generator.getPrimes();\n        System.out.println(\"Generated \" + primes.size() + \" prime numbers\");\n        System.out.println(\"First 10 primes: \" + primes.subList(0, Math.min(10, primes.size())));\n    }\n}\n\nclass PrimeGenerator implements Runnable {\n    private volatile boolean cancelled = false;\n    private final List<Integer> primes = Collections.synchronizedList(new ArrayList<>());\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    public void start() {\n        executor.submit(this);\n    }\n    \n    public void cancel() {\n        cancelled = true;\n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public List<Integer> getPrimes() {\n        synchronized (primes) {\n            return new ArrayList<>(primes);\n        }\n    }\n    \n    @Override\n    public void run() {\n        int num = 2;\n        while (!cancelled) {\n            if (isPrime(num)) {\n                primes.add(num);\n            }\n            num++;\n        }\n    }\n    \n    private boolean isPrime(int n) {\n        if (n <= 1) return false;\n        if (n <= 3) return true;\n        if (n % 2 == 0 || n % 3 == 0) return false;\n        \n        for (int i = 5; i * i <= n; i += 6) {\n            if (n % i == 0 || n % (i + 2) == 0) {\n                return false;\n            }\n        }\n        return true;\n    }\n}",
            "import java.util.ArrayList;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PrimeGeneratorProgram {\n    \n    public static void main(String[] args) throws InterruptedException {\n        PrimeGenerator generator = new PrimeGenerator();\n        ExecutorService executor = Executors.newSingleThreadExecutor();\n        \n        executor.submit(generator);\n        \n        Thread.sleep(1000);\n        \n        generator.cancel();\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        List<Integer> primes = generator.getPrimes();\n        System.out.println(\"Generated primes: \" + primes);\n    }\n}\n\nclass PrimeGenerator implements Runnable {\n    private volatile boolean cancelled = false;\n    private final List<Integer> primes = Collections.synchronizedList(new ArrayList<>());\n    private static final int MAX_PRIMES = 10;\n    \n    @Override\n    public void run() {\n        int number = 2;\n        while (!cancelled && primes.size() < MAX_PRIMES) {\n            if (isPrime(number)) {\n                primes.add(number);\n            }\n            number++;\n        }\n    }\n    \n    private boolean isPrime(int n) {\n        if (n <= 1) return false;\n        if (n <= 3) return true;\n        if (n % 2 == 0 || n % 3 == 0) return false;\n        \n        for (int i = 5; i * i <= n; i += 6) {\n            if (n % i == 0 || n % (i + 2) == 0) {\n                return false;\n            }\n        }\n        return true;\n    }\n    \n    public void cancel() {\n        cancelled = true;\n    }\n    \n    public List<Integer> getPrimes() {\n        synchronized (primes) {\n            return new ArrayList<>(primes);\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.math.BigInteger;\nimport java.util.ArrayList;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.atomic.AtomicBoolean;\n\npublic class LLMC implements Runnable {\n\n    private final List<BigInteger> primes =\n            Collections.synchronizedList(new ArrayList<>());\n    private final AtomicBoolean cancelled = new AtomicBoolean(false);\n    private final int maxPrimes;\n\n    public LLMC(int maxPrimes) {\n        this.maxPrimes = maxPrimes;\n    }\n\n    @Override\n    public void run() {\n        BigInteger p = BigInteger.ONE;\n\n        while (!cancelled.get() && sizeLessThanMax()) {\n            p = p.nextProbablePrime();\n            // synchronizedList ensures thread-safe add\n            primes.add(p);\n\n            try {\n                Thread.sleep(10);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                break;\n            }\n        }\n    }\n\n    private boolean sizeLessThanMax() {\n        synchronized (primes) {\n            return primes.size() < maxPrimes;\n        }\n    }\n\n    public void cancel() {\n        cancelled.set(true);\n    }\n\n    public List<BigInteger> getPrimes() {\n        synchronized (primes) {\n            return new ArrayList<>(primes);\n        }\n    }\n\n    public static List<BigInteger> limitedPrimes() throws InterruptedException {\n        LLMC generator = new LLMC(10);\n        Thread thread = new Thread(generator);\n        thread.start();\n\n        Thread.sleep(1000); // let it run for 1s\n        generator.cancel();\n\n        thread.join();\n\n        return generator.getPrimes();\n    }\n\n    public static void main(String[] args) {\n        try {\n            List<BigInteger> primes = limitedPrimes();\n            System.out.println(\"Generated \" + primes.size() + \" primes in 1 second:\");\n            for (BigInteger prime : primes) {\n                System.out.println(prime);\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            System.err.println(\"Prime generation was interrupted.\");\n        }\n    }\n}",
        "max_depth": "214",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.02%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 32.93%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=130097,visited=64032,backtracked=192150,end=63972\nsearch:             maxDepth=2140,constraints=93\nchoice generators:  thread=130034 (signal=0,lock=13,sharedRef=51,threadApi=2,reschedule=63976), data=0\nheap:               new=1216819,released=3391301,maxLive=733,gcCycles=194129\ninstructions:       83190929\nmax memory:         1006MB\nloaded code:        classes=144,methods=2683\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.33%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 32.29%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=114172,visited=57009,backtracked=170812,end=56705\nsearch:             maxDepth=2140,constraints=78\nchoice generators:  thread=114120 (signal=0,lock=35,sharedRef=173,threadApi=5,reschedule=56731), data=0\nheap:               new=1987562,released=3347594,maxLive=744,gcCycles=171181\ninstructions:       81717396\nmax memory:         1007MB\nloaded code:        classes=146,methods=2716\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.03%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 32.89%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=129663,visited=63872,backtracked=191667,end=63812\nsearch:             maxDepth=2140,constraints=90\nchoice generators:  thread=129602 (signal=0,lock=13,sharedRef=51,threadApi=2,reschedule=63816), data=0\nheap:               new=1213777,released=3382805,maxLive=733,gcCycles=193535\ninstructions:       82978631\nmax memory:         1006MB\nloaded code:        classes=144,methods=2683\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            50.83,
            61.29,
            50.83
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Guarding state with a private lock. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class that encapsulates an object and uses a private lock to synchronize access to it. The class should have a member variable representing some state (e.g., a Widget object), which is guarded by the private lock. Include a method where critical sections are protected using the synchronized keyword on the private lock, ensuring thread-safe access or modification of the guarded state. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ThreadSafeWidgetManager {\n    private final Object lock = new Object();\n    private Widget widget;\n    \n    public ThreadSafeWidgetManager() {\n        this.widget = new Widget(0);\n    }\n    \n    public void incrementValue() {\n        synchronized (lock) {\n            int currentValue = widget.getValue();\n            widget.setValue(currentValue + 1);\n        }\n    }\n    \n    public void decrementValue() {\n        synchronized (lock) {\n            int currentValue = widget.getValue();\n            widget.setValue(currentValue - 1);\n        }\n    }\n    \n    public int getValue() {\n        synchronized (lock) {\n            return widget.getValue();\n        }\n    }\n    \n    public void updateWidget(int newValue) {\n        synchronized (lock) {\n            widget = new Widget(newValue);\n        }\n    }\n    \n    public static void main(String[] args) {\n        ThreadSafeWidgetManager manager = new ThreadSafeWidgetManager();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 1000; i++) {\n                manager.incrementValue();\n                if (i % 100 == 0) {\n                    System.out.println(\"Thread 1 - Current value: \" + manager.getValue());\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 500; i++) {\n                manager.decrementValue();\n                if (i % 50 == 0) {\n                    System.out.println(\"Thread 2 - Current value: \" + manager.getValue());\n                }\n            }\n            manager.updateWidget(100);\n            System.out.println(\"Thread 2 - Updated widget to: \" + manager.getValue());\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final value: \" + manager.getValue());\n    }\n}\n\nclass Widget {\n    private int value;\n    \n    public Widget(int value) {\n        this.value = value;\n    }\n    \n    public int getValue() {\n        return value;\n    }\n    \n    public void setValue(int value) {\n        this.value = value;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ThreadSafeWidgetManager {\n    private final Object lock = new Object();\n    private Widget widget;\n    \n    public ThreadSafeWidgetManager() {\n        this.widget = new Widget(0, \"Initial\");\n    }\n    \n    public void updateWidget(int value, String name) {\n        synchronized (lock) {\n            widget.setValue(value);\n            widget.setName(name);\n            System.out.println(Thread.currentThread().getName() + \" updated widget: \" + widget);\n        }\n    }\n    \n    public Widget getWidget() {\n        synchronized (lock) {\n            return new Widget(widget.getValue(), widget.getName());\n        }\n    }\n    \n    public void incrementValue() {\n        synchronized (lock) {\n            int currentValue = widget.getValue();\n            widget.setValue(currentValue + 1);\n            System.out.println(Thread.currentThread().getName() + \" incremented to: \" + widget.getValue());\n        }\n    }\n    \n    public static void main(String[] args) {\n        ThreadSafeWidgetManager manager = new ThreadSafeWidgetManager();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                manager.incrementValue();\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 3; i++) {\n                manager.updateWidget(i * 10, \"Thread2-\" + i);\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(2, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final widget state: \" + manager.getWidget());\n    }\n}\n\nclass Widget {\n    private int value;\n    private String name;\n    \n    public Widget(int value, String name) {\n        this.value = value;\n        this.name = name;\n    }\n    \n    public int getValue() {\n        return value;\n    }\n    \n    public void setValue(int value) {\n        this.value = value;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public void setName(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Widget{value=\" + value + \", name='\" + name + \"'}\";\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class ThreadSafeWidgetManager {\n    private final Object lock = new Object();\n    private Widget widget;\n    \n    public ThreadSafeWidgetManager() {\n        this.widget = new Widget(0, \"Initial\");\n    }\n    \n    public void updateWidget(int value, String name) {\n        synchronized (lock) {\n            widget.setValue(value);\n            widget.setName(name);\n            System.out.println(Thread.currentThread().getName() + \" updated widget: \" + widget);\n        }\n    }\n    \n    public Widget getWidget() {\n        synchronized (lock) {\n            return new Widget(widget.getValue(), widget.getName());\n        }\n    }\n    \n    public void incrementValue() {\n        synchronized (lock) {\n            int currentValue = widget.getValue();\n            widget.setValue(currentValue + 1);\n            System.out.println(Thread.currentThread().getName() + \" incremented to: \" + widget.getValue());\n        }\n    }\n    \n    public static void main(String[] args) {\n        ThreadSafeWidgetManager manager = new ThreadSafeWidgetManager();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                manager.updateWidget(i * 10, \"Thread1-\" + i);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                manager.incrementValue();\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final widget state: \" + manager.getWidget());\n    }\n}\n\nclass Widget {\n    private int value;\n    private String name;\n    \n    public Widget(int value, String name) {\n        this.value = value;\n        this.name = name;\n    }\n    \n    public int getValue() {\n        return value;\n    }\n    \n    public void setValue(int value) {\n        this.value = value;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public void setName(String name) {\n        this.name = name;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Widget{value=\" + value + \", name='\" + name + \"'}\";\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "/**\n* PrivateLock\n* Guarding state with a private lock.\n* Rewritten to use explicit threads for JPF compatibility.\n*/\npublic class PrivateLock {\nprivate final Object myLock = new Object();\nprivate Widget widget;\n\npublic void someMethod() {\nsynchronized (myLock) {\nif (widget == null) {\nSystem.out.println(Thread.currentThread().getName() + \" initializing widget.\");\nwidget = new Widget();\n}\nwidget.doSomething();\n}\n}\n\nstatic class Widget {\nvoid doSomething() {\nSystem.out.println(Thread.currentThread().getName() + \" is doing something with widget.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nPrivateLock privateLock = new PrivateLock();\n\nThread t1 = new Thread(privateLock::someMethod);\nThread t2 = new Thread(privateLock::someMethod);\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All threads have finished.\");\n}\n}",
        "max_depth": "15",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.03%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.39%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.40%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=167562,visited=133675,backtracked=301093,end=0\nsearch:             maxDepth=150,constraints=75361\nchoice generators:  thread=104196 (signal=0,lock=28072,sharedRef=63695,threadApi=2,reschedule=16), data=0\nheap:               new=434526,released=125185,maxLive=736,gcCycles=301237\ninstructions:       29741687\nmax memory:         1020MB\nloaded code:        classes=135,methods=2398\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.02%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.83%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.84%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=129095,visited=161009,backtracked=289977,end=2\nsearch:             maxDepth=150,constraints=35348\nchoice generators:  thread=100479 (signal=0,lock=16230,sharedRef=65818,threadApi=12298,reschedule=1570), data=0\nheap:               new=704406,released=346342,maxLive=748,gcCycles=287652\ninstructions:       35593838\nmax memory:         1020MB\nloaded code:        classes=137,methods=2418\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.03%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.58%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.87%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=159566,visited=132083,backtracked=291520,end=0\nsearch:             maxDepth=150,constraints=69866\nchoice generators:  thread=100315 (signal=0,lock=15882,sharedRef=62237,threadApi=9467,reschedule=580), data=0\nheap:               new=568932,released=275916,maxLive=748,gcCycles=288161\ninstructions:       29340973\nmax memory:         1020MB\nloaded code:        classes=137,methods=2418\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            63.84,
            62.81,
            62.81
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Hash-based map using lock striping. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called StripedMap that implements a hash-based map using lock striping for concurrency control. The map should use an array of buckets to store key-value pairs, and an array of lock objects to synchronize access to the buckets. Each bucket at index n should be guarded by the lock at index n % N_LOCKS, where N_LOCKS is a constant set to 16. Implement a static inner class Node to represent entries in the map, with fields for the key, value, and a reference to the next node in case of collisions. Include a constructor that initializes the number of buckets, and methods for computing the hash index, retrieving values based on a key, and clearing all entries from the map. Ensure thread safety by synchronizing on the appropriate lock object in both the get and clear methods. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 5. Use a fixed thread pool or manually manage at most 4 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class StripedMap<K, V> {\n    private static final int N_LOCKS = 16;\n    private final Node<K, V>[] buckets;\n    private final Object[] locks;\n\n    static class Node<K, V> {\n        final K key;\n        V value;\n        Node<K, V> next;\n\n        Node(K key, V value, Node<K, V> next) {\n            this.key = key;\n            this.value = value;\n            this.next = next;\n        }\n    }\n\n    @SuppressWarnings(\"unchecked\")\n    public StripedMap(int numBuckets) {\n        buckets = new Node[numBuckets];\n        locks = new Object[N_LOCKS];\n        for (int i = 0; i < N_LOCKS; i++) {\n            locks[i] = new Object();\n        }\n    }\n\n    private int hash(K key) {\n        return Math.abs(key.hashCode() % buckets.length);\n    }\n\n    public V get(K key) {\n        int hash = hash(key);\n        synchronized (locks[hash % N_LOCKS]) {\n            Node<K, V> node = buckets[hash];\n            while (node != null) {\n                if (node.key.equals(key)) {\n                    return node.value;\n                }\n                node = node.next;\n            }\n            return null;\n        }\n    }\n\n    public void put(K key, V value) {\n        int hash = hash(key);\n        synchronized (locks[hash % N_LOCKS]) {\n            Node<K, V> node = buckets[hash];\n            if (node == null) {\n                buckets[hash] = new Node<>(key, value, null);\n                return;\n            }\n            while (true) {\n                if (node.key.equals(key)) {\n                    node.value = value;\n                    return;\n                }\n                if (node.next == null) {\n                    node.next = new Node<>(key, value, null);\n                    return;\n                }\n                node = node.next;\n            }\n        }\n    }\n\n    public void clear() {\n        for (int i = 0; i < buckets.length; i++) {\n            synchronized (locks[i % N_LOCKS]) {\n                buckets[i] = null;\n            }\n        }\n    }\n\n    public static void main(String[] args) {\n        StripedMap<Integer, String> map = new StripedMap<>(32);\n        ExecutorService executor = Executors.newFixedThreadPool(4);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                map.put(i, \"Value\" + i);\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                map.put(i, \"Value\" + i);\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 50; i++) {\n                String value = map.get(i);\n                if (value != null) {\n                    System.out.println(\"Key \" + i + \": \" + value);\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            map.clear();\n            System.out.println(\"Map cleared\");\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        for (int i = 0; i < 10; i++) {\n            String value = map.get(i);\n            System.out.println(\"Final check - Key \" + i + \": \" + value);\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class StripedMap<K, V> {\n    private static final int N_LOCKS = 16;\n    private final Node<K, V>[] buckets;\n    private final Object[] locks;\n\n    static class Node<K, V> {\n        final K key;\n        V value;\n        Node<K, V> next;\n\n        Node(K key, V value, Node<K, V> next) {\n            this.key = key;\n            this.value = value;\n            this.next = next;\n        }\n    }\n\n    @SuppressWarnings(\"unchecked\")\n    public StripedMap(int numBuckets) {\n        buckets = (Node<K, V>[]) new Node[numBuckets];\n        locks = new Object[N_LOCKS];\n        for (int i = 0; i < N_LOCKS; i++) {\n            locks[i] = new Object();\n        }\n    }\n\n    private int hash(K key) {\n        return Math.abs(key.hashCode() % buckets.length);\n    }\n\n    public V get(K key) {\n        int hash = hash(key);\n        synchronized (locks[hash % N_LOCKS]) {\n            Node<K, V> node = buckets[hash];\n            while (node != null) {\n                if (node.key.equals(key)) {\n                    return node.value;\n                }\n                node = node.next;\n            }\n            return null;\n        }\n    }\n\n    public void put(K key, V value) {\n        int hash = hash(key);\n        synchronized (locks[hash % N_LOCKS]) {\n            Node<K, V> node = buckets[hash];\n            if (node == null) {\n                buckets[hash] = new Node<>(key, value, null);\n                return;\n            }\n            while (true) {\n                if (node.key.equals(key)) {\n                    node.value = value;\n                    return;\n                }\n                if (node.next == null) {\n                    node.next = new Node<>(key, value, null);\n                    return;\n                }\n                node = node.next;\n            }\n        }\n    }\n\n    public void clear() {\n        for (int i = 0; i < buckets.length; i++) {\n            synchronized (locks[i % N_LOCKS]) {\n                buckets[i] = null;\n            }\n        }\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        StripedMap<Integer, String> map = new StripedMap<>(32);\n        ExecutorService executor = Executors.newFixedThreadPool(4);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                map.put(i, \"Value\" + i);\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                map.put(i, \"Value\" + i);\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 200; i++) {\n                String value = map.get(i);\n                if (value != null) {\n                    System.out.println(\"Thread 3: Key \" + i + \" = \" + value);\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            map.clear();\n            System.out.println(\"Map cleared\");\n        });\n\n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n\n        for (int i = 0; i < 10; i++) {\n            String value = map.get(i);\n            System.out.println(\"Main thread: Key \" + i + \" = \" + value);\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class StripedMap<K, V> {\n    private static final int N_LOCKS = 16;\n    private final Node<K, V>[] buckets;\n    private final Object[] locks;\n\n    static class Node<K, V> {\n        final K key;\n        V value;\n        Node<K, V> next;\n\n        Node(K key, V value, Node<K, V> next) {\n            this.key = key;\n            this.value = value;\n            this.next = next;\n        }\n    }\n\n    @SuppressWarnings(\"unchecked\")\n    public StripedMap(int numBuckets) {\n        buckets = new Node[numBuckets];\n        locks = new Object[N_LOCKS];\n        for (int i = 0; i < N_LOCKS; i++) {\n            locks[i] = new Object();\n        }\n    }\n\n    private int hash(K key) {\n        return Math.abs(key.hashCode() % buckets.length);\n    }\n\n    public V get(K key) {\n        int hash = hash(key);\n        synchronized (locks[hash % N_LOCKS]) {\n            Node<K, V> node = buckets[hash];\n            while (node != null) {\n                if (node.key.equals(key)) {\n                    return node.value;\n                }\n                node = node.next;\n            }\n            return null;\n        }\n    }\n\n    public void put(K key, V value) {\n        int hash = hash(key);\n        synchronized (locks[hash % N_LOCKS]) {\n            Node<K, V> node = buckets[hash];\n            if (node == null) {\n                buckets[hash] = new Node<>(key, value, null);\n                return;\n            }\n            while (true) {\n                if (node.key.equals(key)) {\n                    node.value = value;\n                    return;\n                }\n                if (node.next == null) {\n                    node.next = new Node<>(key, value, null);\n                    return;\n                }\n                node = node.next;\n            }\n        }\n    }\n\n    public void clear() {\n        for (int i = 0; i < buckets.length; i++) {\n            synchronized (locks[i % N_LOCKS]) {\n                buckets[i] = null;\n            }\n        }\n    }\n\n    public static void main(String[] args) {\n        StripedMap<Integer, String> map = new StripedMap<>(32);\n        ExecutorService executor = Executors.newFixedThreadPool(4);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                map.put(i, \"Value\" + i);\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 100; i < 200; i++) {\n                map.put(i, \"Value\" + i);\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 200; i++) {\n                String value = map.get(i);\n                if (value != null) {\n                    System.out.println(\"Key: \" + i + \", Value: \" + value);\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            map.clear();\n            System.out.println(\"Map cleared\");\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            false
        ],
        "ground_truth": "public class StripedMap {\nprivate static final int N_LOCKS = 4;\nprivate final Node[] buckets;\nprivate final Object[] locks;\n\nprivate static class Node {\nfinal Object key;\nObject value;\nNode next;\n\nNode(Object key, Object value, Node next) {\nthis.key = key;\nthis.value = value;\nthis.next = next;\n}\n}\n\npublic StripedMap(int numBuckets) {\nbuckets = new Node[numBuckets];\nlocks = new Object[N_LOCKS];\nfor (int i = 0; i < N_LOCKS; i++) locks[i] = new Object();\n}\n\nprivate int hash(Object key) {\nint h = key == null ? 0 : key.hashCode();\nreturn (h & 0x7fffffff) % buckets.length;\n}\n\npublic Object get(Object key) {\nint h = hash(key);\nObject lock = locks[h % N_LOCKS];\nsynchronized (lock) {\nNode node = buckets[h];\nwhile (node != null) {\nif (node.key == null ? key == null : node.key.equals(key))\nreturn node.value;\nnode = node.next;\n}\nreturn null;\n}\n}\n\npublic void put(Object key, Object value) {\nint h = hash(key);\nObject lock = locks[h % N_LOCKS];\nsynchronized (lock) {\nNode head = buckets[h];\nfor (Node node = head; node != null; node = node.next) {\nif (node.key == null ? key == null : node.key.equals(key)) {\nnode.value = value;\nreturn;\n}\n}\nbuckets[h] = new Node(key, value, head);\n}\n}\n\npublic void clear() {\nfor (int i = 0; i < buckets.length; i++) {\nObject lock = locks[i % N_LOCKS];\nsynchronized (lock) {\nbuckets[i] = null;\n}\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal StripedMap map = new StripedMap(8);\n\nThread writer1 = new Thread(() -> {\nfor (int i = 0; i < 2; i++) map.put(\"k\" + i, i);\n});\n\nThread writer2 = new Thread(() -> {\nfor (int i = 1; i < 2; i++) map.put(\"k\" + i, i*10);\n});\n\nThread reader = new Thread(() -> {\nfor (int i = 0; i < 2; i++) map.get(\"k\" + i);\n});\n\nThread clearer = new Thread(map::clear);\n\nwriter1.start();\nwriter2.start();\nreader.start();\nclearer.start();\n\nwriter1.join();\nwriter2.join();\nreader.join();\nclearer.join();\n\nmap.get(\"k0\");\nmap.get(\"k2\");\n}\n}",
        "max_depth": "99",
        "jpf_details": [
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.55%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 79.55%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 79.55%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 79.55%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 79.55%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=89032,visited=89283,backtracked=177336,end=0\nsearch:             maxDepth=990,constraints=82120\nchoice generators:  thread=36443 (signal=0,lock=648,sharedRef=28238,threadApi=873,reschedule=1263), data=0\nheap:               new=4262689,released=27526,maxLive=1040,gcCycles=178315\ninstructions:       13642964\nmax memory:         1018MB\nloaded code:        classes=135,methods=2400\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.61%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 79.56%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 79.56%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 79.56%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 79.55%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=89501,visited=89585,backtracked=178098,end=0\nsearch:             maxDepth=990,constraints=82505\nchoice generators:  thread=36597 (signal=0,lock=625,sharedRef=28367,threadApi=875,reschedule=1272), data=0\nheap:               new=4260024,released=27713,maxLive=1040,gcCycles=179086\ninstructions:       13659611\nmax memory:         1018MB\nloaded code:        classes=135,methods=2400\n\n====================================================== search finished",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nStripedMap.main()\n====================================================== search started: 11/17/25 3:24 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            50.77,
            54.09,
            50.5
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Immutable Point class used by DelegatingVehicleTracker. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create an immutable class named Point that represents a coordinate in a two-dimensional space. The class should have two public final fields, x and y, both of type int, to store the coordinates. The class should include a constructor that takes two integer parameters to initialize the x and y values. Ensure that no methods are added that could modify the state of the object after creation. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 6. Use a fixed thread pool or manually manage at most 5 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.Random;\n\npublic class PointDemo {\n    public static void main(String[] args) {\n        ConcurrentHashMap<Integer, Point> pointMap = new ConcurrentHashMap<>();\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        Random random = new Random();\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadId = i;\n            executor.submit(() -> {\n                for (int j = 0; j < 10; j++) {\n                    int x = random.nextInt(100);\n                    int y = random.nextInt(100);\n                    Point point = new Point(x, y);\n                    int key = threadId * 10 + j;\n                    pointMap.put(key, point);\n                    System.out.println(\"Thread \" + threadId + \" created Point(\" + point.x + \", \" + point.y + \")\");\n                }\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Total points created: \" + pointMap.size());\n        pointMap.forEach((key, point) -> {\n            System.out.println(\"Key: \" + key + \" -> Point(\" + point.x + \", \" + point.y + \")\");\n        });\n    }\n}\n\nfinal class Point {\n    public final int x;\n    public final int y;\n    \n    public Point(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class PointDemo {\n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        AtomicInteger counter = new AtomicInteger(0);\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadId = i;\n            executor.submit(() -> {\n                for (int j = 0; j < 10; j++) {\n                    int value = counter.incrementAndGet();\n                    Point point = new Point(threadId * 10 + j, value);\n                    System.out.println(\"Thread \" + threadId + \" created: Point(\" + point.x + \", \" + point.y + \")\");\n                    try {\n                        Thread.sleep(50);\n                    } catch (InterruptedException e) {\n                        Thread.currentThread().interrupt();\n                    }\n                }\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"All threads completed. Total points created: \" + counter.get());\n    }\n}\n\nfinal class Point {\n    public final int x;\n    public final int y;\n    \n    public Point(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.ConcurrentHashMap;\nimport java.util.List;\nimport java.util.ArrayList;\nimport java.util.Random;\n\npublic class PointDemo {\n    public static void main(String[] args) throws InterruptedException {\n        ExecutorService executor = Executors.newFixedThreadPool(5);\n        ConcurrentHashMap<Integer, Point> pointMap = new ConcurrentHashMap<>();\n        Random random = new Random();\n        \n        for (int i = 0; i < 5; i++) {\n            final int threadId = i;\n            executor.submit(() -> {\n                for (int j = 0; j < 10; j++) {\n                    int x = random.nextInt(100);\n                    int y = random.nextInt(100);\n                    Point point = new Point(x, y);\n                    int key = threadId * 10 + j;\n                    pointMap.put(key, point);\n                    System.out.println(\"Thread \" + threadId + \" created point: (\" + point.x + \", \" + point.y + \")\");\n                }\n            });\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        System.out.println(\"\\nAll points created:\");\n        pointMap.forEach((key, point) -> {\n            System.out.println(\"Key \" + key + \": (\" + point.x + \", \" + point.y + \")\");\n        });\n    }\n}\n\nfinal class Point {\n    public final int x;\n    public final int y;\n    \n    public Point(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "/**\n* Demonstrates creating Points in parallel threads without using ExecutorService.\n*/\nclass Point {\npublic final int x, y;\n\npublic Point(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\n@Override\npublic String toString() {\nreturn \"Point{\" +\n\"x=\" + x +\n\", y=\" + y +\n'}';\n}\n}\n\npublic class Main {\npublic static void main(String[] args) throws InterruptedException {\nThread[] threads = new Thread[5];\n\nfor (int i = 1; i <= 5; i++) {\nfinal int taskId = i;\nthreads[i - 1] = new Thread(() -> {\nPoint point = new Point(taskId * 10, taskId * 20);\nSystem.out.println(\"Task ID: \" + taskId + \", Generated Point: \" + point);\n});\n}\n\n// Start all threads\nfor (Thread t : threads) {\nt.start();\n}\n\n// Wait for all threads to finish\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"All tasks completed.\");\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.40%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.54%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.54%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.54%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.54%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=96826,visited=130271,backtracked=226897,end=0\nsearch:             maxDepth=200,constraints=107514\nchoice generators:  thread=38722 (signal=0,lock=407,sharedRef=34775,threadApi=5,reschedule=307), data=0\nheap:               new=757117,released=301488,maxLive=1095,gcCycles=227097\ninstructions:       20134390\nmax memory:         1019MB\nloaded code:        classes=146,methods=2571\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 83.04%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 83.04%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 83.04%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 83.04%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 83.04%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=137925,visited=112016,backtracked=249742,end=0\nsearch:             maxDepth=200,constraints=156029\nchoice generators:  thread=42377 (signal=0,lock=7,sharedRef=34103,threadApi=1179,reschedule=272), data=0\nheap:               new=161131,released=177207,maxLive=755,gcCycles=249941\ninstructions:       17078133\nmax memory:         1019MB\nloaded code:        classes=135,methods=2390\n\n====================================================== search finished",
            "Unique logical threads created during execution: 6\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 82.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 82.56%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 82.56%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 82.56%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 82.56%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=98312,visited=134257,backtracked=232375,end=0\nsearch:             maxDepth=200,constraints=108968\nchoice generators:  thread=39632 (signal=0,lock=407,sharedRef=35685,threadApi=5,reschedule=305), data=0\nheap:               new=679780,released=192823,maxLive=1095,gcCycles=232569\ninstructions:       19722487\nmax memory:         1019MB\nloaded code:        classes=146,methods=2571\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            58.18,
            52.18,
            54.67
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Immutable class built out of mutable underlying objects. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named ThreeStooges that represents an immutable collection of names belonging to the Three Stooges (Moe, Larry, and Curly). The class should use a Set internally to store these names and provide a method to check if a given name is one of the Stooges. Additionally, include a method that returns a string representation of all Stooge names in list format. Ensure that the internal collection remains immutable from the outside, even though it is built using mutable objects. Use appropriate concurrency annotations to indicate thread-safety or immutability where applicable. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class ThreeStooges {\n    private final Set<String> stooges;\n    \n    public ThreeStooges() {\n        Set<String> tempSet = new HashSet<>();\n        tempSet.add(\"Moe\");\n        tempSet.add(\"Larry\");\n        tempSet.add(\"Curly\");\n        this.stooges = Collections.unmodifiableSet(tempSet);\n    }\n    \n    public boolean isStooge(String name) {\n        return stooges.contains(name);\n    }\n    \n    public String getStoogesAsString() {\n        return stooges.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ThreeStooges threeStooges = new ThreeStooges();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkMoe = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Moe\");\n            return threeStooges.isStooge(\"Moe\");\n        });\n        \n        Future<Boolean> checkBob = executor.submit(() -> {\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Bob\");\n            return threeStooges.isStooge(\"Bob\");\n        });\n        \n        System.out.println(\"Main thread: All Stooges: \" + threeStooges.getStoogesAsString());\n        System.out.println(\"Is Moe a Stooge? \" + checkMoe.get());\n        System.out.println(\"Is Bob a Stooge? \" + checkBob.get());\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class ThreeStooges {\n    private final Set<String> stooges;\n    \n    public ThreeStooges() {\n        Set<String> tempSet = new HashSet<>();\n        tempSet.add(\"Moe\");\n        tempSet.add(\"Larry\");\n        tempSet.add(\"Curly\");\n        this.stooges = Collections.unmodifiableSet(tempSet);\n    }\n    \n    public boolean isStooge(String name) {\n        return stooges.contains(name);\n    }\n    \n    public String getStoogesAsString() {\n        return stooges.toString();\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ThreeStooges threeStooges = new ThreeStooges();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Boolean> checkMoe = executor.submit(() -> {\n            boolean result = threeStooges.isStooge(\"Moe\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking Moe: \" + result);\n            return result;\n        });\n        \n        Future<Boolean> checkJohn = executor.submit(() -> {\n            boolean result = threeStooges.isStooge(\"John\");\n            System.out.println(\"Thread \" + Thread.currentThread().getName() + \" checking John: \" + result);\n            return result;\n        });\n        \n        System.out.println(\"Main thread: All Stooges: \" + threeStooges.getStoogesAsString());\n        \n        Boolean moeResult = checkMoe.get();\n        Boolean johnResult = checkJohn.get();\n        \n        System.out.println(\"Main thread: Final results - Moe: \" + moeResult + \", John: \" + johnResult);\n        \n        executor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class ThreeStooges {\n    private final Set<String> stooges;\n\n    public ThreeStooges() {\n        Set<String> tempSet = new HashSet<>();\n        tempSet.add(\"Moe\");\n        tempSet.add(\"Larry\");\n        tempSet.add(\"Curly\");\n        this.stooges = Collections.unmodifiableSet(tempSet);\n    }\n\n    public boolean isStooge(String name) {\n        return stooges.contains(name);\n    }\n\n    public String getStoogesAsString() {\n        return stooges.toString();\n    }\n\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ThreeStooges threeStooges = new ThreeStooges();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        Future<Boolean> future1 = executor.submit(() -> {\n            boolean result = threeStooges.isStooge(\"Moe\");\n            System.out.println(\"Thread 1: Is Moe a Stooge? \" + result);\n            return result;\n        });\n\n        Future<Boolean> future2 = executor.submit(() -> {\n            boolean result = threeStooges.isStooge(\"Shemp\");\n            System.out.println(\"Thread 2: Is Shemp a Stooge? \" + result);\n            return result;\n        });\n\n        System.out.println(\"Main thread: All Stooges: \" + threeStooges.getStoogesAsString());\n        \n        Boolean result1 = future1.get();\n        Boolean result2 = future2.get();\n        \n        System.out.println(\"Main thread: Results received - Moe: \" + result1 + \", Shemp: \" + result2);\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\n/**\n* ThreeStooges\n*\n* A truly immutable class using an unmodifiable set,\n* suitable for safe concurrent access and model checking with JPF.\n*/\npublic final class ThreeStooges {\nprivate final Set<String> stooges;\n\npublic ThreeStooges() {\nSet<String> temp = new HashSet<>();\ntemp.add(\"Moe\");\ntemp.add(\"Larry\");\ntemp.add(\"Curly\");\nthis.stooges = Collections.unmodifiableSet(temp);\n}\n\npublic boolean isStooge(String name) {\nreturn stooges.contains(name);\n}\n\npublic String getStoogeNames() {\n// This method returns a string representation of the stooge names\nreturn new ArrayList<>(stooges).toString();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nThreeStooges threeStooges = new ThreeStooges();\n\nThread t1 = new Thread(() -> {\nString[] names = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\"};\nfor (String name : names) {\nboolean result = threeStooges.isStooge(name);\nSystem.out.println(\"Thread-1: isStooge(\" + name + \") = \" + result);\n}\nSystem.out.println(\"Thread-1: Stooge names: \" + threeStooges.getStoogeNames());\n});\n\nThread t2 = new Thread(() -> {\nString[] names = {\"Moe\", \"Larry\", \"Curly\", \"Shemp\"};\nfor (String name : names) {\nboolean result = threeStooges.isStooge(name);\nSystem.out.println(\"Thread-2: isStooge(\" + name + \") = \" + result);\n}\nSystem.out.println(\"Thread-2: Stooge names: \" + threeStooges.getStoogeNames());\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All threads have finished execution.\");\n}\n}",
        "max_depth": "97",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.15%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 25.57%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.57%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=123165,visited=86091,backtracked=208508,end=45511\nsearch:             maxDepth=970,constraints=4040\nchoice generators:  thread=120428 (signal=0,lock=4,sharedRef=49163,threadApi=2,reschedule=63762), data=0\nheap:               new=606255,released=2762571,maxLive=762,gcCycles=209256\ninstructions:       89959791\nmax memory:         1014MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 61.98%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 60.44%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.73%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=58388,visited=101204,backtracked=159592,end=253\nsearch:             maxDepth=92,constraints=0\nchoice generators:  thread=58384 (signal=0,lock=6164,sharedRef=39085,threadApi=491,reschedule=4816), data=0\nheap:               new=240901,released=146934,maxLive=759,gcCycles=153499\ninstructions:       11596216\nmax memory:         1012MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.10%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 25.45%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 31.32%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=126129,visited=87972,backtracked=213529,end=46910\nsearch:             maxDepth=970,constraints=4098\nchoice generators:  thread=123355 (signal=0,lock=4,sharedRef=50084,threadApi=2,reschedule=65586), data=0\nheap:               new=620397,released=2843592,maxLive=760,gcCycles=214101\ninstructions:       92279557\nmax memory:         1014MB\nloaded code:        classes=142,methods=2466\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            56.95,
            59.43,
            56.66
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Immutable holder for caching a number and its factors. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class that represents an immutable cache for storing a number and its factors. The class should store a single number as a BigInteger and its corresponding factors as an array of BigInteger. It should provide a method to retrieve the cached factors if the input number matches the stored number, otherwise return null. The returned factors array should be a copy to prevent modification of the internal state. Ensure thread safety by making the class immutable using appropriate patterns. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.math.BigInteger;\nimport java.util.Arrays;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FactorCache {\n    private final BigInteger number;\n    private final BigInteger[] factors;\n    \n    public FactorCache(BigInteger number, BigInteger[] factors) {\n        this.number = number;\n        this.factors = factors != null ? Arrays.copyOf(factors, factors.length) : null;\n    }\n    \n    public BigInteger[] getFactors(BigInteger inputNumber) {\n        if (inputNumber != null && inputNumber.equals(number)) {\n            return factors != null ? Arrays.copyOf(factors, factors.length) : null;\n        }\n        return null;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        BigInteger[] factors1 = {BigInteger.valueOf(2), BigInteger.valueOf(3), BigInteger.valueOf(5)};\n        FactorCache cache1 = new FactorCache(BigInteger.valueOf(30), factors1);\n        \n        BigInteger[] factors2 = {BigInteger.valueOf(2), BigInteger.valueOf(2), BigInteger.valueOf(7)};\n        FactorCache cache2 = new FactorCache(BigInteger.valueOf(28), factors2);\n        \n        executor.submit(() -> {\n            BigInteger[] result = cache1.getFactors(BigInteger.valueOf(30));\n            if (result != null) {\n                System.out.println(\"Thread 1 - Factors of 30: \" + Arrays.toString(result));\n            }\n            \n            BigInteger[] result2 = cache1.getFactors(BigInteger.valueOf(28));\n            if (result2 == null) {\n                System.out.println(\"Thread 1 - No match for 28 in cache1\");\n            }\n        });\n        \n        executor.submit(() -> {\n            BigInteger[] result = cache2.getFactors(BigInteger.valueOf(28));\n            if (result != null) {\n                System.out.println(\"Thread 2 - Factors of 28: \" + Arrays.toString(result));\n            }\n            \n            BigInteger[] result2 = cache2.getFactors(BigInteger.valueOf(30));\n            if (result2 == null) {\n                System.out.println(\"Thread 2 - No match for 30 in cache2\");\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.math.BigInteger;\nimport java.util.Arrays;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FactorCache {\n    private final BigInteger number;\n    private final BigInteger[] factors;\n    \n    public FactorCache(BigInteger number, BigInteger[] factors) {\n        this.number = number;\n        this.factors = factors != null ? Arrays.copyOf(factors, factors.length) : null;\n    }\n    \n    public BigInteger[] getFactors(BigInteger inputNumber) {\n        if (inputNumber != null && inputNumber.equals(number)) {\n            return factors != null ? Arrays.copyOf(factors, factors.length) : null;\n        }\n        return null;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        BigInteger[] factors1 = {BigInteger.valueOf(2), BigInteger.valueOf(3), BigInteger.valueOf(5)};\n        FactorCache cache1 = new FactorCache(BigInteger.valueOf(30), factors1);\n        \n        BigInteger[] factors2 = {BigInteger.valueOf(2), BigInteger.valueOf(2), BigInteger.valueOf(7)};\n        FactorCache cache2 = new FactorCache(BigInteger.valueOf(28), factors2);\n        \n        executor.submit(() -> {\n            BigInteger[] result = cache1.getFactors(BigInteger.valueOf(30));\n            if (result != null) {\n                System.out.println(\"Thread 1 - Factors of 30: \" + Arrays.toString(result));\n            }\n            \n            result = cache1.getFactors(BigInteger.valueOf(28));\n            if (result == null) {\n                System.out.println(\"Thread 1 - No factors found for 28 in cache1\");\n            }\n        });\n        \n        executor.submit(() -> {\n            BigInteger[] result = cache2.getFactors(BigInteger.valueOf(28));\n            if (result != null) {\n                System.out.println(\"Thread 2 - Factors of 28: \" + Arrays.toString(result));\n            }\n            \n            result = cache2.getFactors(BigInteger.valueOf(30));\n            if (result == null) {\n                System.out.println(\"Thread 2 - No factors found for 30 in cache2\");\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.math.BigInteger;\nimport java.util.Arrays;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class FactorCache {\n    private final BigInteger number;\n    private final BigInteger[] factors;\n    \n    public FactorCache(BigInteger number, BigInteger[] factors) {\n        this.number = number;\n        this.factors = factors == null ? null : Arrays.copyOf(factors, factors.length);\n    }\n    \n    public BigInteger[] getFactors(BigInteger inputNumber) {\n        if (inputNumber == null || number == null) {\n            return null;\n        }\n        if (inputNumber.equals(number)) {\n            return factors == null ? null : Arrays.copyOf(factors, factors.length);\n        }\n        return null;\n    }\n    \n    public BigInteger getNumber() {\n        return number;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        BigInteger num1 = new BigInteger(\"12\");\n        BigInteger[] factors1 = {new BigInteger(\"2\"), new BigInteger(\"2\"), new BigInteger(\"3\")};\n        FactorCache cache1 = new FactorCache(num1, factors1);\n        \n        BigInteger num2 = new BigInteger(\"30\");\n        BigInteger[] factors2 = {new BigInteger(\"2\"), new BigInteger(\"3\"), new BigInteger(\"5\")};\n        FactorCache cache2 = new FactorCache(num2, factors2);\n        \n        executor.submit(() -> {\n            BigInteger[] result = cache1.getFactors(new BigInteger(\"12\"));\n            if (result != null) {\n                System.out.println(\"Thread 1 - Found factors for 12: \" + Arrays.toString(result));\n            }\n            \n            result = cache1.getFactors(new BigInteger(\"30\"));\n            if (result == null) {\n                System.out.println(\"Thread 1 - No factors found for 30 in cache1\");\n            }\n        });\n        \n        executor.submit(() -> {\n            BigInteger[] result = cache2.getFactors(new BigInteger(\"30\"));\n            if (result != null) {\n                System.out.println(\"Thread 2 - Found factors for 30: \" + Arrays.toString(result));\n            }\n            \n            result = cache2.getFactors(new BigInteger(\"12\"));\n            if (result == null) {\n                System.out.println(\"Thread 2 - No factors found for 12 in cache2\");\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Main thread - Program completed\");\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.math.BigInteger;\nimport java.util.Arrays;\nimport java.util.ArrayList;\nimport java.util.List;\n\n/**\n* Immutable cache storing one number and its factors.\n*/\nfinal class OneValueCache {\nprivate final BigInteger lastNumber;\nprivate final BigInteger[] lastFactors;\n\npublic OneValueCache(BigInteger i, BigInteger[] factors) {\nthis.lastNumber = i;\nif (factors != null) {\nthis.lastFactors = Arrays.copyOf(factors, factors.length);\n} else {\nthis.lastFactors = null;\n}\n}\n\npublic BigInteger[] getFactors(BigInteger i) {\nif (lastNumber == null || !lastNumber.equals(i)) {\nreturn null;\n}\nif (lastFactors == null) {\nreturn null;\n}\nreturn Arrays.copyOf(lastFactors, lastFactors.length);\n}\n}\n\n/**\n* A factorizer with synchronized cache access.\n* Avoids using volatile or thread pool to remain JPF-compatible.\n*/\npublic class FactorizerWithCache {\nprivate static OneValueCache cache = new OneValueCache(null, null);\n\npublic static BigInteger[] factor(BigInteger n) {\nList<BigInteger> factors = new ArrayList<>();\nBigInteger i = BigInteger.valueOf(2);\n\nwhile (i.multiply(i).compareTo(n) <= 0) {\nwhile (n.mod(i).equals(BigInteger.ZERO)) {\nfactors.add(i);\nn = n.divide(i);\n}\ni = i.add(BigInteger.ONE);\n}\n\nif (n.compareTo(BigInteger.ONE) > 0) {\nfactors.add(n);\n}\n\nreturn factors.toArray(new BigInteger[0]);\n}\n\npublic static void handleRequest(BigInteger number, int threadId) {\nBigInteger[] cachedFactors;\n\nsynchronized (FactorizerWithCache.class) {\ncachedFactors = cache.getFactors(number);\n\nif (cachedFactors == null) {\nSystem.out.println(\"Thread \" + threadId + \": Cache miss for \" + number + \", computing...\");\nBigInteger[] factors = factor(number);\ncache = new OneValueCache(number, factors);\ncachedFactors = cache.getFactors(number);\n} else {\nSystem.out.println(\"Thread \" + threadId + \": Cache hit for \" + number);\n}\n}\n\nSystem.out.print(\"Thread \" + threadId + \": Factors of \" + number + \" are \");\nSystem.out.println(Arrays.toString(cachedFactors));\n}\n\npublic static void main(String[] args) throws InterruptedException {\nBigInteger numberToFactor = new BigInteger(\"100\");\n\nThread t1 = new Thread(() -> handleRequest(numberToFactor, 1));\nThread t2 = new Thread(() -> handleRequest(numberToFactor, 2));\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All threads have finished execution.\");\n}\n}",
        "max_depth": "123",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nFactorCache.main()\n====================================================== search started: 11/17/25 3:27 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nFactorCache.main()\n====================================================== search started: 11/17/25 3:27 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nFactorCache.main()\n====================================================== search started: 11/17/25 3:27 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            54.35,
            54.35,
            53.83
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Implementing put-if-absent using composition. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named ImproveList that implements the List interface and enhances it by providing a thread-safe putIfAbsent method. The class should wrap an existing List instance, which is provided via the constructor. All methods of the List interface should delegate to the underlying list. Ensure that all mutative operations (e.g., add, remove, addAll, etc.) are synchronized to maintain atomicity, especially for the putIfAbsent method. The putIfAbsent method should check if the specified element is already present in the list; if not, it should add the element and return true, otherwise return false. Make sure the class is properly documented and follows good design practices.. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass ImprovedList<E> implements List<E> {\n    private final List<E> list;\n    private final Object lock = new Object();\n\n    public ImprovedList(List<E> list) {\n        this.list = list;\n    }\n\n    public boolean putIfAbsent(E e) {\n        synchronized (lock) {\n            if (!list.contains(e)) {\n                list.add(e);\n                return true;\n            }\n            return false;\n        }\n    }\n\n    @Override\n    public int size() {\n        synchronized (lock) {\n            return list.size();\n        }\n    }\n\n    @Override\n    public boolean isEmpty() {\n        synchronized (lock) {\n            return list.isEmpty();\n        }\n    }\n\n    @Override\n    public boolean contains(Object o) {\n        synchronized (lock) {\n            return list.contains(o);\n        }\n    }\n\n    @Override\n    public Iterator<E> iterator() {\n        synchronized (lock) {\n            return new ArrayList<>(list).iterator();\n        }\n    }\n\n    @Override\n    public Object[] toArray() {\n        synchronized (lock) {\n            return list.toArray();\n        }\n    }\n\n    @Override\n    public <T> T[] toArray(T[] a) {\n        synchronized (lock) {\n            return list.toArray(a);\n        }\n    }\n\n    @Override\n    public boolean add(E e) {\n        synchronized (lock) {\n            return list.add(e);\n        }\n    }\n\n    @Override\n    public boolean remove(Object o) {\n        synchronized (lock) {\n            return list.remove(o);\n        }\n    }\n\n    @Override\n    public boolean containsAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.containsAll(c);\n        }\n    }\n\n    @Override\n    public boolean addAll(Collection<? extends E> c) {\n        synchronized (lock) {\n            return list.addAll(c);\n        }\n    }\n\n    @Override\n    public boolean addAll(int index, Collection<? extends E> c) {\n        synchronized (lock) {\n            return list.addAll(index, c);\n        }\n    }\n\n    @Override\n    public boolean removeAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.removeAll(c);\n        }\n    }\n\n    @Override\n    public boolean retainAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.retainAll(c);\n        }\n    }\n\n    @Override\n    public void clear() {\n        synchronized (lock) {\n            list.clear();\n        }\n    }\n\n    @Override\n    public E get(int index) {\n        synchronized (lock) {\n            return list.get(index);\n        }\n    }\n\n    @Override\n    public E set(int index, E element) {\n        synchronized (lock) {\n            return list.set(index, element);\n        }\n    }\n\n    @Override\n    public void add(int index, E element) {\n        synchronized (lock) {\n            list.add(index, element);\n        }\n    }\n\n    @Override\n    public E remove(int index) {\n        synchronized (lock) {\n            return list.remove(index);\n        }\n    }\n\n    @Override\n    public int indexOf(Object o) {\n        synchronized (lock) {\n            return list.indexOf(o);\n        }\n    }\n\n    @Override\n    public int lastIndexOf(Object o) {\n        synchronized (lock) {\n            return list.lastIndexOf(o);\n        }\n    }\n\n    @Override\n    public ListIterator<E> listIterator() {\n        synchronized (lock) {\n            return new ArrayList<>(list).listIterator();\n        }\n    }\n\n    @Override\n    public ListIterator<E> listIterator(int index) {\n        synchronized (lock) {\n            return new ArrayList<>(list).listIterator(index);\n        }\n    }\n\n    @Override\n    public List<E> subList(int fromIndex, int toIndex) {\n        synchronized (lock) {\n            return new ArrayList<>(list.subList(fromIndex, toIndex));\n        }\n    }\n}\n\npublic class ImproveList {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ImprovedList<Integer> improvedList = new ImprovedList<>(new ArrayList<>());\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                improvedList.putIfAbsent(i);\n                if (i % 2 == 0) {\n                    improvedList.add(i + 1000);\n                }\n            }\n            return null;\n        });\n\n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 50; i < 150; i++) {\n                improvedList.putIfAbsent(i);\n                if (i % 3 == 0) {\n                    improvedList.remove(Integer.valueOf(i));\n                }\n            }\n            return null;\n        });\n\n        task1.get();\n        task2.get();\n\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n\n        System.out.println(\"Final list size: \" + improvedList.size());\n        System.out.println(\"Contains 25: \" + improvedList.contains(25));\n        System.out.println(\"Contains 75: \" + improvedList.contains(75));\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class ImproveList<E> implements List<E> {\n    private final List<E> list;\n    private final Object lock = new Object();\n\n    public ImproveList(List<E> list) {\n        this.list = list;\n    }\n\n    public boolean putIfAbsent(E e) {\n        synchronized (lock) {\n            if (!list.contains(e)) {\n                list.add(e);\n                return true;\n            }\n            return false;\n        }\n    }\n\n    @Override\n    public int size() {\n        synchronized (lock) {\n            return list.size();\n        }\n    }\n\n    @Override\n    public boolean isEmpty() {\n        synchronized (lock) {\n            return list.isEmpty();\n        }\n    }\n\n    @Override\n    public boolean contains(Object o) {\n        synchronized (lock) {\n            return list.contains(o);\n        }\n    }\n\n    @Override\n    public Iterator<E> iterator() {\n        synchronized (lock) {\n            return new ArrayList<>(list).iterator();\n        }\n    }\n\n    @Override\n    public Object[] toArray() {\n        synchronized (lock) {\n            return list.toArray();\n        }\n    }\n\n    @Override\n    public <T> T[] toArray(T[] a) {\n        synchronized (lock) {\n            return list.toArray(a);\n        }\n    }\n\n    @Override\n    public boolean add(E e) {\n        synchronized (lock) {\n            return list.add(e);\n        }\n    }\n\n    @Override\n    public boolean remove(Object o) {\n        synchronized (lock) {\n            return list.remove(o);\n        }\n    }\n\n    @Override\n    public boolean containsAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.containsAll(c);\n        }\n    }\n\n    @Override\n    public boolean addAll(Collection<? extends E> c) {\n        synchronized (lock) {\n            return list.addAll(c);\n        }\n    }\n\n    @Override\n    public boolean addAll(int index, Collection<? extends E> c) {\n        synchronized (lock) {\n            return list.addAll(index, c);\n        }\n    }\n\n    @Override\n    public boolean removeAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.removeAll(c);\n        }\n    }\n\n    @Override\n    public boolean retainAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.retainAll(c);\n        }\n    }\n\n    @Override\n    public void clear() {\n        synchronized (lock) {\n            list.clear();\n        }\n    }\n\n    @Override\n    public E get(int index) {\n        synchronized (lock) {\n            return list.get(index);\n        }\n    }\n\n    @Override\n    public E set(int index, E element) {\n        synchronized (lock) {\n            return list.set(index, element);\n        }\n    }\n\n    @Override\n    public void add(int index, E element) {\n        synchronized (lock) {\n            list.add(index, element);\n        }\n    }\n\n    @Override\n    public E remove(int index) {\n        synchronized (lock) {\n            return list.remove(index);\n        }\n    }\n\n    @Override\n    public int indexOf(Object o) {\n        synchronized (lock) {\n            return list.indexOf(o);\n        }\n    }\n\n    @Override\n    public int lastIndexOf(Object o) {\n        synchronized (lock) {\n            return list.lastIndexOf(o);\n        }\n    }\n\n    @Override\n    public ListIterator<E> listIterator() {\n        synchronized (lock) {\n            return new ArrayList<>(list).listIterator();\n        }\n    }\n\n    @Override\n    public ListIterator<E> listIterator(int index) {\n        synchronized (lock) {\n            return new ArrayList<>(list).listIterator(index);\n        }\n    }\n\n    @Override\n    public List<E> subList(int fromIndex, int toIndex) {\n        synchronized (lock) {\n            return new ArrayList<>(list.subList(fromIndex, toIndex));\n        }\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        ImproveList<Integer> improveList = new ImproveList<>(new ArrayList<>());\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        CountDownLatch latch = new CountDownLatch(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                boolean added = improveList.putIfAbsent(i);\n                System.out.println(\"Thread 1: putIfAbsent(\" + i + \") = \" + added);\n            }\n            latch.countDown();\n        });\n\n        executor.submit(() -> {\n            for (int i = 5; i < 15; i++) {\n                boolean added = improveList.putIfAbsent(i);\n                System.out.println(\"Thread 2: putIfAbsent(\" + i + \") = \" + added);\n            }\n            latch.countDown();\n        });\n\n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n\n        System.out.println(\"Final list: \" + improveList);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass ImprovedList<E> implements List<E> {\n    private final List<E> list;\n    private final Object lock = new Object();\n\n    public ImprovedList(List<E> list) {\n        this.list = list;\n    }\n\n    public boolean putIfAbsent(E e) {\n        synchronized (lock) {\n            if (!list.contains(e)) {\n                return list.add(e);\n            }\n            return false;\n        }\n    }\n\n    @Override\n    public int size() {\n        synchronized (lock) {\n            return list.size();\n        }\n    }\n\n    @Override\n    public boolean isEmpty() {\n        synchronized (lock) {\n            return list.isEmpty();\n        }\n    }\n\n    @Override\n    public boolean contains(Object o) {\n        synchronized (lock) {\n            return list.contains(o);\n        }\n    }\n\n    @Override\n    public Iterator<E> iterator() {\n        synchronized (lock) {\n            return new ArrayList<>(list).iterator();\n        }\n    }\n\n    @Override\n    public Object[] toArray() {\n        synchronized (lock) {\n            return list.toArray();\n        }\n    }\n\n    @Override\n    public <T> T[] toArray(T[] a) {\n        synchronized (lock) {\n            return list.toArray(a);\n        }\n    }\n\n    @Override\n    public boolean add(E e) {\n        synchronized (lock) {\n            return list.add(e);\n        }\n    }\n\n    @Override\n    public boolean remove(Object o) {\n        synchronized (lock) {\n            return list.remove(o);\n        }\n    }\n\n    @Override\n    public boolean containsAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.containsAll(c);\n        }\n    }\n\n    @Override\n    public boolean addAll(Collection<? extends E> c) {\n        synchronized (lock) {\n            return list.addAll(c);\n        }\n    }\n\n    @Override\n    public boolean addAll(int index, Collection<? extends E> c) {\n        synchronized (lock) {\n            return list.addAll(index, c);\n        }\n    }\n\n    @Override\n    public boolean removeAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.removeAll(c);\n        }\n    }\n\n    @Override\n    public boolean retainAll(Collection<?> c) {\n        synchronized (lock) {\n            return list.retainAll(c);\n        }\n    }\n\n    @Override\n    public void clear() {\n        synchronized (lock) {\n            list.clear();\n        }\n    }\n\n    @Override\n    public E get(int index) {\n        synchronized (lock) {\n            return list.get(index);\n        }\n    }\n\n    @Override\n    public E set(int index, E element) {\n        synchronized (lock) {\n            return list.set(index, element);\n        }\n    }\n\n    @Override\n    public void add(int index, E element) {\n        synchronized (lock) {\n            list.add(index, element);\n        }\n    }\n\n    @Override\n    public E remove(int index) {\n        synchronized (lock) {\n            return list.remove(index);\n        }\n    }\n\n    @Override\n    public int indexOf(Object o) {\n        synchronized (lock) {\n            return list.indexOf(o);\n        }\n    }\n\n    @Override\n    public int lastIndexOf(Object o) {\n        synchronized (lock) {\n            return list.lastIndexOf(o);\n        }\n    }\n\n    @Override\n    public ListIterator<E> listIterator() {\n        synchronized (lock) {\n            return new ArrayList<>(list).listIterator();\n        }\n    }\n\n    @Override\n    public ListIterator<E> listIterator(int index) {\n        synchronized (lock) {\n            return new ArrayList<>(list).listIterator(index);\n        }\n    }\n\n    @Override\n    public List<E> subList(int fromIndex, int toIndex) {\n        synchronized (lock) {\n            return new ArrayList<>(list.subList(fromIndex, toIndex));\n        }\n    }\n}\n\npublic class ImproveList {\n    public static void main(String[] args) throws InterruptedException {\n        ImprovedList<Integer> improvedList = new ImprovedList<>(new ArrayList<>());\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        CountDownLatch latch = new CountDownLatch(2);\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 100; i++) {\n                    improvedList.putIfAbsent(i);\n                    if (i % 2 == 0) {\n                        improvedList.add(i + 1000);\n                    }\n                }\n            } finally {\n                latch.countDown();\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                for (int i = 50; i < 150; i++) {\n                    improvedList.putIfAbsent(i);\n                    if (i % 3 == 0) {\n                        improvedList.remove(Integer.valueOf(i));\n                    }\n                }\n            } finally {\n                latch.countDown();\n            }\n        });\n\n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n\n        System.out.println(\"Final list size: \" + improvedList.size());\n        System.out.println(\"Contains 25: \" + improvedList.contains(25));\n        System.out.println(\"Contains 75: \" + improvedList.contains(75));\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\n/**\n* ImprovedList\n*\n* Implementing putIfAbsent using composition and synchronization\n*/\npublic class ImprovedList<T> implements List<T> {\nprivate final List<T> list;\n\n/**\n* PRE: list argument is thread-safe.\n*/\npublic ImprovedList(List<T> list) {\nthis.list = list;\n}\n\npublic synchronized boolean putIfAbsent(T x) {\nboolean contains = list.contains(x);\nif (!contains)\nlist.add(x);\nreturn !contains;\n}\n\n// Plain vanilla delegation for List methods.\n// Mutative methods must be synchronized to ensure atomicity of putIfAbsent.\n\npublic int size() {\nreturn list.size();\n}\n\npublic boolean isEmpty() {\nreturn list.isEmpty();\n}\n\npublic boolean contains(Object o) {\nreturn list.contains(o);\n}\n\npublic Iterator<T> iterator() {\nreturn list.iterator();\n}\n\npublic Object[] toArray() {\nreturn list.toArray();\n}\n\npublic <E> E[] toArray(E[] a) {\nreturn list.toArray(a);\n}\n\npublic synchronized boolean add(T e) {\nreturn list.add(e);\n}\n\npublic synchronized boolean remove(Object o) {\nreturn list.remove(o);\n}\n\npublic boolean containsAll(Collection<?> c) {\nreturn list.containsAll(c);\n}\n\npublic synchronized boolean addAll(Collection<? extends T> c) {\nreturn list.addAll(c);\n}\n\npublic synchronized boolean addAll(int index, Collection<? extends T> c) {\nreturn list.addAll(index, c);\n}\n\npublic synchronized boolean removeAll(Collection<?> c) {\nreturn list.removeAll(c);\n}\n\npublic synchronized boolean retainAll(Collection<?> c) {\nreturn list.retainAll(c);\n}\n\npublic boolean equals(Object o) {\nreturn list.equals(o);\n}\n\npublic int hashCode() {\nreturn list.hashCode();\n}\n\npublic T get(int index) {\nreturn list.get(index);\n}\n\npublic synchronized T set(int index, T element) {\nreturn list.set(index, element);\n}\n\npublic synchronized void add(int index, T element) {\nlist.add(index, element);\n}\n\npublic synchronized T remove(int index) {\nreturn list.remove(index);\n}\n\npublic int indexOf(Object o) {\nreturn list.indexOf(o);\n}\n\npublic int lastIndexOf(Object o) {\nreturn list.lastIndexOf(o);\n}\n\npublic ListIterator<T> listIterator() {\nreturn list.listIterator();\n}\n\npublic ListIterator<T> listIterator(int index) {\nreturn list.listIterator(index);\n}\n\npublic List<T> subList(int fromIndex, int toIndex) {\nreturn list.subList(fromIndex, toIndex);\n}\n\npublic synchronized void clear() {\nlist.clear();\n}\n\n@Override\npublic String toString() {\nreturn list.toString();\n}\n\n// === MAIN METHOD FOR TESTING CONCURRENCY ===\n\npublic static void main(String[] args) throws InterruptedException, ExecutionException {\nList<String> syncList = Collections.synchronizedList(new ArrayList<>());\nImprovedList<String> improvedList = new ImprovedList<>(syncList);\n\nint threadCount = 2;\nExecutorService executor = Executors.newFixedThreadPool(threadCount);\n\nList<Callable<Void>> tasks = new ArrayList<>();\nfor (int i = 0; i < threadCount; i++) {\nfinal String element = \"Item\";\ntasks.add(() -> {\nboolean added = improvedList.putIfAbsent(element);\nSystem.out.println(Thread.currentThread().getName() + \" putIfAbsent result: \" + added);\nreturn null;\n});\n}\n\nList<Future<Void>> futures = executor.invokeAll(tasks);\nfor (Future<Void> future : futures) {\nfuture.get();\n}\n\nexecutor.shutdown();\n\nSystem.out.println(\"Final list size: \" + improvedList.size());\nSystem.out.println(\"Final list contents: \" + improvedList);\n}\n}",
        "max_depth": "107",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 38.33%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.18%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=149166,visited=67832,backtracked=215937,end=0\nsearch:             maxDepth=1070,constraints=7781\nchoice generators:  thread=141754 (signal=0,lock=71494,sharedRef=53384,threadApi=2,reschedule=16873), data=0\nheap:               new=4977,released=2751,maxLive=995,gcCycles=216968\ninstructions:       64939887\nmax memory:         1015MB\nloaded code:        classes=134,methods=2631\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 20.59%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 38.96%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 55.39%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=79654,visited=68465,backtracked=147129,end=5328\nsearch:             maxDepth=1070,constraints=18339\nchoice generators:  thread=63747 (signal=0,lock=15,sharedRef=21124,threadApi=2,reschedule=32082), data=0\nheap:               new=1027856,released=1535201,maxLive=1014,gcCycles=148118\ninstructions:       78585342\nmax memory:         1012MB\nloaded code:        classes=144,methods=2706\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 38.28%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 61.22%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=149195,visited=68026,backtracked=216179,end=0\nsearch:             maxDepth=1070,constraints=7734\nchoice generators:  thread=141838 (signal=0,lock=71456,sharedRef=53393,threadApi=2,reschedule=16986), data=0\nheap:               new=5088,released=2848,maxLive=1007,gcCycles=217188\ninstructions:       64021509\nmax memory:         1015MB\nloaded code:        classes=136,methods=2642\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            74.89,
            75.89,
            76.42
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Inducing a lock ordering to avoid deadlock. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that performs a thread-safe money transfer between two accounts while avoiding deadlock by inducing a consistent lock ordering. The program should use the account object's identity hash code to determine the lock acquisition order. If both accounts have the same hash code, introduce a secondary tie-breaking lock to ensure consistent locking and prevent deadlock. Implement a helper class to carry out the actual transfer logic, which checks for sufficient funds before performing the debit and credit operations. Define interfaces for Account and DollarAmount, and include an exception class for insufficient funds scenarios. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface DollarAmount {\n    long getAmount();\n}\n\ninterface Account {\n    void debit(DollarAmount amount) throws InsufficientFundsException;\n    void credit(DollarAmount amount);\n    DollarAmount getBalance();\n}\n\nclass InsufficientFundsException extends Exception {\n    public InsufficientFundsException(String message) {\n        super(message);\n    }\n}\n\nclass DollarAmountImpl implements DollarAmount {\n    private final long amount;\n    \n    public DollarAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass AccountImpl implements Account {\n    private long balance;\n    private final Lock lock = new ReentrantLock();\n    \n    public AccountImpl(long initialBalance) {\n        this.balance = initialBalance;\n    }\n    \n    public void debit(DollarAmount amount) throws InsufficientFundsException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientFundsException(\"Insufficient funds\");\n        }\n        balance -= amount.getAmount();\n    }\n    \n    public void credit(DollarAmount amount) {\n        balance += amount.getAmount();\n    }\n    \n    public DollarAmount getBalance() {\n        return new DollarAmountImpl(balance);\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieLock = new ReentrantLock();\n    \n    public static void transfer(AccountImpl fromAccount, AccountImpl toAccount, DollarAmount amount) \n            throws InsufficientFundsException {\n        int fromHash = System.identityHashCode(fromAccount);\n        int toHash = System.identityHashCode(toAccount);\n        \n        if (fromHash < toHash) {\n            fromAccount.getLock().lock();\n            try {\n                toAccount.getLock().lock();\n                try {\n                    doTransfer(fromAccount, toAccount, amount);\n                } finally {\n                    toAccount.getLock().unlock();\n                }\n            } finally {\n                fromAccount.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            toAccount.getLock().lock();\n            try {\n                fromAccount.getLock().lock();\n                try {\n                    doTransfer(fromAccount, toAccount, amount);\n                } finally {\n                    fromAccount.getLock().unlock();\n                }\n            } finally {\n                toAccount.getLock().unlock();\n            }\n        } else {\n            tieLock.lock();\n            try {\n                fromAccount.getLock().lock();\n                try {\n                    toAccount.getLock().lock();\n                    try {\n                        doTransfer(fromAccount, toAccount, amount);\n                    } finally {\n                        toAccount.getLock().unlock();\n                    }\n                } finally {\n                    fromAccount.getLock().unlock();\n                }\n            } finally {\n                tieLock.unlock();\n            }\n        }\n    }\n    \n    private static void doTransfer(AccountImpl fromAccount, AccountImpl toAccount, DollarAmount amount) \n            throws InsufficientFundsException {\n        fromAccount.debit(amount);\n        toAccount.credit(amount);\n    }\n}\n\npublic class MoneyTransferProgram {\n    public static void main(String[] args) {\n        AccountImpl account1 = new AccountImpl(1000);\n        AccountImpl account2 = new AccountImpl(500);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    TransferHelper.transfer(account1, account2, new DollarAmountImpl(100));\n                    System.out.println(\"Transfer 1->2 completed. Balance 1: \" + \n                        account1.getBalance().getAmount() + \", Balance 2: \" + \n                        account2.getBalance().getAmount());\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientFundsException | InterruptedException e) {\n                System.out.println(\"Transfer failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 3; i++) {\n                    TransferHelper.transfer(account2, account1, new DollarAmountImpl(50));\n                    System.out.println(\"Transfer 2->1 completed. Balance 1: \" + \n                        account1.getBalance().getAmount() + \", Balance 2: \" + \n                        account2.getBalance().getAmount());\n                    Thread.sleep(150);\n                }\n            } catch (InsufficientFundsException | InterruptedException e) {\n                System.out.println(\"Transfer failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Final Balance 1: \" + account1.getBalance().getAmount());\n        System.out.println(\"Final Balance 2: \" + account2.getBalance().getAmount());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\npublic class MoneyTransferProgram {\n    \n    private static final Object tieLock = new Object();\n    \n    public static void main(String[] args) {\n        Account account1 = new BankAccount(\"Account1\", new DollarAmountImpl(1000));\n        Account account2 = new BankAccount(\"Account2\", new DollarAmountImpl(500));\n        Account account3 = new BankAccount(\"Account3\", new DollarAmountImpl(750));\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    transferMoney(account1, account2, new DollarAmountImpl(100));\n                    System.out.println(\"Transfer 1->2 completed\");\n                } catch (InsufficientFundsException e) {\n                    System.out.println(\"Transfer 1->2 failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    transferMoney(account2, account3, new DollarAmountImpl(50));\n                    System.out.println(\"Transfer 2->3 completed\");\n                } catch (InsufficientFundsException e) {\n                    System.out.println(\"Transfer 2->3 failed: \" + e.getMessage());\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final balances:\");\n        System.out.println(\"Account1: \" + account1.getBalance().getAmount());\n        System.out.println(\"Account2: \" + account2.getBalance().getAmount());\n        System.out.println(\"Account3: \" + account3.getBalance().getAmount());\n    }\n    \n    public static void transferMoney(Account fromAccount, Account toAccount, DollarAmount amount) \n            throws InsufficientFundsException {\n        int fromHash = System.identityHashCode(fromAccount);\n        int toHash = System.identityHashCode(toAccount);\n        \n        if (fromHash < toHash) {\n            synchronized (fromAccount) {\n                synchronized (toAccount) {\n                    new TransferHelper().doTransfer(fromAccount, toAccount, amount);\n                }\n            }\n        } else if (fromHash > toHash) {\n            synchronized (toAccount) {\n                synchronized (fromAccount) {\n                    new TransferHelper().doTransfer(fromAccount, toAccount, amount);\n                }\n            }\n        } else {\n            synchronized (tieLock) {\n                synchronized (fromAccount) {\n                    synchronized (toAccount) {\n                        new TransferHelper().doTransfer(fromAccount, toAccount, amount);\n                    }\n                }\n            }\n        }\n    }\n}\n\ninterface Account {\n    DollarAmount getBalance();\n    void debit(DollarAmount amount) throws InsufficientFundsException;\n    void credit(DollarAmount amount);\n}\n\ninterface DollarAmount {\n    long getAmount();\n    DollarAmount add(DollarAmount other);\n    DollarAmount subtract(DollarAmount other);\n    boolean isLessThan(DollarAmount other);\n}\n\nclass InsufficientFundsException extends Exception {\n    public InsufficientFundsException(String message) {\n        super(message);\n    }\n}\n\nclass TransferHelper {\n    public void doTransfer(Account fromAccount, Account toAccount, DollarAmount amount) \n            throws InsufficientFundsException {\n        if (fromAccount.getBalance().isLessThan(amount)) {\n            throw new InsufficientFundsException(\"Insufficient funds in source account\");\n        }\n        fromAccount.debit(amount);\n        toAccount.credit(amount);\n    }\n}\n\nclass BankAccount implements Account {\n    private final String name;\n    private DollarAmount balance;\n    \n    public BankAccount(String name, DollarAmount initialBalance) {\n        this.name = name;\n        this.balance = initialBalance;\n    }\n    \n    public DollarAmount getBalance() {\n        return balance;\n    }\n    \n    public void debit(DollarAmount amount) throws InsufficientFundsException {\n        if (balance.isLessThan(amount)) {\n            throw new InsufficientFundsException(\"Cannot debit more than balance\");\n        }\n        balance = balance.subtract(amount);\n    }\n    \n    public void credit(DollarAmount amount) {\n        balance = balance.add(amount);\n    }\n}\n\nclass DollarAmountImpl implements DollarAmount {\n    private final long amount;\n    \n    public DollarAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    public long getAmount() {\n        return amount;\n    }\n    \n    public DollarAmount add(DollarAmount other) {\n        return new DollarAmountImpl(amount + other.getAmount());\n    }\n    \n    public DollarAmount subtract(DollarAmount other) {\n        return new DollarAmountImpl(amount - other.getAmount());\n    }\n    \n    public boolean isLessThan(DollarAmount other) {\n        return amount < other.getAmount();\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.locks.Lock;\nimport java.util.concurrent.locks.ReentrantLock;\n\ninterface DollarAmount {\n    long getAmount();\n}\n\ninterface Account {\n    void debit(DollarAmount amount) throws InsufficientFundsException;\n    void credit(DollarAmount amount);\n    DollarAmount getBalance();\n}\n\nclass InsufficientFundsException extends Exception {\n    public InsufficientFundsException(String message) {\n        super(message);\n    }\n}\n\nclass DollarAmountImpl implements DollarAmount {\n    private final long amount;\n    \n    public DollarAmountImpl(long amount) {\n        this.amount = amount;\n    }\n    \n    public long getAmount() {\n        return amount;\n    }\n}\n\nclass AccountImpl implements Account {\n    private long balance;\n    private final Lock lock = new ReentrantLock();\n    \n    public AccountImpl(long initialBalance) {\n        this.balance = initialBalance;\n    }\n    \n    public void debit(DollarAmount amount) throws InsufficientFundsException {\n        if (balance < amount.getAmount()) {\n            throw new InsufficientFundsException(\"Insufficient funds\");\n        }\n        balance -= amount.getAmount();\n    }\n    \n    public void credit(DollarAmount amount) {\n        balance += amount.getAmount();\n    }\n    \n    public DollarAmount getBalance() {\n        return new DollarAmountImpl(balance);\n    }\n    \n    public Lock getLock() {\n        return lock;\n    }\n}\n\nclass TransferHelper {\n    private static final Lock tieLock = new ReentrantLock();\n    \n    public static void transfer(AccountImpl fromAccount, AccountImpl toAccount, DollarAmount amount) \n            throws InsufficientFundsException {\n        int fromHash = System.identityHashCode(fromAccount);\n        int toHash = System.identityHashCode(toAccount);\n        \n        if (fromHash < toHash) {\n            fromAccount.getLock().lock();\n            try {\n                toAccount.getLock().lock();\n                try {\n                    doTransfer(fromAccount, toAccount, amount);\n                } finally {\n                    toAccount.getLock().unlock();\n                }\n            } finally {\n                fromAccount.getLock().unlock();\n            }\n        } else if (fromHash > toHash) {\n            toAccount.getLock().lock();\n            try {\n                fromAccount.getLock().lock();\n                try {\n                    doTransfer(fromAccount, toAccount, amount);\n                } finally {\n                    fromAccount.getLock().unlock();\n                }\n            } finally {\n                toAccount.getLock().unlock();\n            }\n        } else {\n            tieLock.lock();\n            try {\n                fromAccount.getLock().lock();\n                try {\n                    toAccount.getLock().lock();\n                    try {\n                        doTransfer(fromAccount, toAccount, amount);\n                    } finally {\n                        toAccount.getLock().unlock();\n                    }\n                } finally {\n                    fromAccount.getLock().unlock();\n                }\n            } finally {\n                tieLock.unlock();\n            }\n        }\n    }\n    \n    private static void doTransfer(AccountImpl fromAccount, AccountImpl toAccount, DollarAmount amount) \n            throws InsufficientFundsException {\n        fromAccount.debit(amount);\n        toAccount.credit(amount);\n    }\n}\n\npublic class MoneyTransfer {\n    public static void main(String[] args) {\n        AccountImpl account1 = new AccountImpl(1000);\n        AccountImpl account2 = new AccountImpl(500);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    TransferHelper.transfer(account1, account2, new DollarAmountImpl(100));\n                    System.out.println(\"Transfer 1->2 completed. Balance 1: \" + \n                        account1.getBalance().getAmount() + \", Balance 2: \" + \n                        account2.getBalance().getAmount());\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientFundsException | InterruptedException e) {\n                System.out.println(\"Transfer failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 5; i++) {\n                    TransferHelper.transfer(account2, account1, new DollarAmountImpl(50));\n                    System.out.println(\"Transfer 2->1 completed. Balance 1: \" + \n                        account1.getBalance().getAmount() + \", Balance 2: \" + \n                        account2.getBalance().getAmount());\n                    Thread.sleep(100);\n                }\n            } catch (InsufficientFundsException | InterruptedException e) {\n                System.out.println(\"Transfer failed: \" + e.getMessage());\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        System.out.println(\"Final Balance 1: \" + account1.getBalance().getAmount());\n        System.out.println(\"Final Balance 2: \" + account2.getBalance().getAmount());\n    }\n}"
        ],
        "graded_list": [
            false,
            true,
            false
        ],
        "ground_truth": "import java.math.BigDecimal;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class LLMC {\nprivate static final Object tieLock = new Object();\n\npublic void transferMoney(final Account fromAcct,\nfinal Account toAcct,\nfinal DollarAmount amount)\nthrows InsufficientFundsException {\nclass Helper {\npublic void transfer() throws InsufficientFundsException {\nif (fromAcct.getBalance().compareTo(amount) < 0)\nthrow new InsufficientFundsException();\nelse {\nfromAcct.debit(amount);\ntoAcct.credit(amount);\n}\n}\n}\n\nint fromHash = System.identityHashCode(fromAcct);\nint toHash = System.identityHashCode(toAcct);\n\nif (fromHash < toHash) {\nsynchronized (fromAcct) {\nsynchronized (toAcct) {\nnew Helper().transfer();\n}\n}\n} else if (fromHash > toHash) {\nsynchronized (toAcct) {\nsynchronized (fromAcct) {\nnew Helper().transfer();\n}\n}\n} else {\nsynchronized (tieLock) {\nsynchronized (fromAcct) {\nsynchronized (toAcct) {\nnew Helper().transfer();\n}\n}\n}\n}\n}\n\npublic static class DollarAmount implements Comparable<DollarAmount> {\nprivate final BigDecimal value;\n\npublic DollarAmount(BigDecimal value) {\nthis.value = value;\n}\n\npublic DollarAmount add(DollarAmount other) {\nreturn new DollarAmount(this.value.add(other.value));\n}\n\npublic DollarAmount subtract(DollarAmount other) {\nreturn new DollarAmount(this.value.subtract(other.value));\n}\n\n@Override\npublic int compareTo(DollarAmount other) {\nreturn this.value.compareTo(other.value);\n}\n\n@Override\npublic String toString() {\nreturn value.toString();\n}\n}\n\npublic interface Account {\nvoid debit(DollarAmount d);\n\nvoid credit(DollarAmount d);\n\nDollarAmount getBalance();\n\nint getAcctNo();\n}\n\npublic static class AccountImpl implements Account {\nprivate DollarAmount balance;\nprivate final int acctNo;\n\npublic AccountImpl(int acctNo, DollarAmount initialBalance) {\nthis.acctNo = acctNo;\nthis.balance = initialBalance;\n}\n\n@Override\npublic synchronized void debit(DollarAmount d) {\nbalance = balance.subtract(d);\n}\n\n@Override\npublic synchronized void credit(DollarAmount d) {\nbalance = balance.add(d);\n}\n\n@Override\npublic synchronized DollarAmount getBalance() {\nreturn balance;\n}\n\n@Override\npublic int getAcctNo() {\nreturn acctNo;\n}\n}\n\nstatic class InsufficientFundsException extends Exception {\npublic InsufficientFundsException() {\nsuper(\"Insufficient funds in account.\");\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC service = new LLMC();\n\nAccount a1 = new AccountImpl(1, new DollarAmount(new BigDecimal(\"1000.00\")));\nAccount a2 = new AccountImpl(2, new DollarAmount(new BigDecimal(\"1000.00\")));\n\nRunnable task = () -> {\ntry {\n// Reduced iterations to 2 for faster completion\nfor (int i = 0; i < 2; i++) {\nservice.transferMoney(a1, a2, new DollarAmount(new BigDecimal(\"1.00\")));\nservice.transferMoney(a2, a1, new DollarAmount(new BigDecimal(\"1.00\")));\n}\n} catch (InsufficientFundsException e) {\ne.printStackTrace();\n}\n};\n\n// Reduced thread pool size to 2 to reduce thread overhead\nExecutorService executor = Executors.newFixedThreadPool(2);\n// Reduced number of tasks to 2\nfor (int i = 0; i < 2; i++) {\nexecutor.submit(task);\n}\n\nexecutor.shutdown();\nwhile (!executor.isTerminated()) {\nThread.sleep(10);\n}\n\nSystem.out.println(\"Final balance of Account 1: \" + ((AccountImpl) a1).getBalance());\nSystem.out.println(\"Final balance of Account 2: \" + ((AccountImpl) a2).getBalance());\n}\n}",
        "max_depth": "211",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.24%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.25%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field AccountImpl@1c9.balance   pool-1-th...\"\n\n====================================================== statistics\nstates:             new=87026,visited=16465,backtracked=101381,end=0\nsearch:             maxDepth=2110,constraints=58722\nchoice generators:  thread=35938 (signal=0,lock=259,sharedRef=21538,threadApi=44,reschedule=29), data=0\nheap:               new=51662,released=29361,maxLive=756,gcCycles=103490\ninstructions:       4716470\nmax memory:         995MB\nloaded code:        classes=139,methods=2406\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.12%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.02%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=211575,visited=82990,backtracked=292462,end=0\nsearch:             maxDepth=2110,constraints=127916\nchoice generators:  thread=100754 (signal=0,lock=10151,sharedRef=63148,threadApi=2,reschedule=45), data=0\nheap:               new=350599,released=135481,maxLive=762,gcCycles=289309\ninstructions:       19852640\nmax memory:         1017MB\nloaded code:        classes=141,methods=2429\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 65.96%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 65.96%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field AccountImpl@1c9.balance   pool-1-th...\"\n\n====================================================== statistics\nstates:             new=180369,visited=29899,backtracked=208158,end=0\nsearch:             maxDepth=2110,constraints=124863\nchoice generators:  thread=71552 (signal=0,lock=535,sharedRef=43204,threadApi=66,reschedule=41), data=0\nheap:               new=63973,released=27045,maxLive=756,gcCycles=210267\ninstructions:       8231027\nmax memory:         1012MB\nloaded code:        classes=139,methods=2406\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field AccountImpl@1c9.balance   pool-1-th...\"",
            "no errors detected",
            "error #1: gov.nasa.jpf.listener.PreciseRaceDetector \"race for field AccountImpl@1c9.balance   pool-1-th...\""
        ],
        "codebleu_score": [
            56.56,
            53.57,
            56.56
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Lazy initialization holder class idiom. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java program that implements a thread-safe singleton pattern using a static nested class to lazily initialize a resource. The main class should provide a public static method to access the singleton instance. Simulate resource initialization by adding a delay in the constructor and assign a unique ID to each instance using its identity hash code. Include a main method that starts multiple threads to concurrently access the singleton resource and print its ID along with the thread name. Ensure that only one instance of the resource is created, even under multi-threaded conditions. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SingletonDemo {\n    \n    private SingletonDemo() {}\n    \n    private static class ResourceHolder {\n        private static final Resource INSTANCE = new Resource();\n    }\n    \n    public static Resource getInstance() {\n        return ResourceHolder.INSTANCE;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            Resource resource = SingletonDemo.getInstance();\n            System.out.println(\"Thread: \" + Thread.currentThread().getName() + \n                             \" - Resource ID: \" + resource.getId());\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass Resource {\n    private final int id;\n    \n    Resource() {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        this.id = System.identityHashCode(this);\n        System.out.println(\"Resource initialized with ID: \" + id);\n    }\n    \n    public int getId() {\n        return id;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SingletonDemo {\n    \n    private static class SingletonResource {\n        private final int id;\n        \n        private SingletonResource() {\n            try {\n                Thread.sleep(1000);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            this.id = System.identityHashCode(this);\n        }\n        \n        private static class Holder {\n            private static final SingletonResource INSTANCE = new SingletonResource();\n        }\n        \n        public static SingletonResource getInstance() {\n            return Holder.INSTANCE;\n        }\n        \n        public int getId() {\n            return id;\n        }\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            SingletonResource resource = SingletonResource.getInstance();\n            System.out.println(\"Thread: \" + Thread.currentThread().getName() + \n                             \", Resource ID: \" + resource.getId());\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        \n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        SingletonResource mainResource = SingletonResource.getInstance();\n        System.out.println(\"Thread: \" + Thread.currentThread().getName() + \n                         \", Resource ID: \" + mainResource.getId());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SingletonDemo {\n    \n    private SingletonDemo() {}\n    \n    private static class ResourceHolder {\n        private static final Resource INSTANCE = new Resource();\n    }\n    \n    public static Resource getInstance() {\n        return ResourceHolder.INSTANCE;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(10);\n        \n        for (int i = 0; i < 10; i++) {\n            executor.submit(() -> {\n                Resource resource = SingletonDemo.getInstance();\n                System.out.println(\"Thread: \" + Thread.currentThread().getName() + \n                                 \" - Resource ID: \" + resource.getId());\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass Resource {\n    private final int id;\n    \n    public Resource() {\n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        this.id = System.identityHashCode(this);\n        System.out.println(\"Resource initialized with ID: \" + id);\n    }\n    \n    public int getId() {\n        return id;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "public class LLMC {\n\nprivate static class ResourceHolder {\nprivate static final Resource resource = new Resource();\n}\n\npublic static Resource getResource() {\nreturn ResourceHolder.resource;\n}\n\nstatic class Resource {\nprivate final long id;\n\npublic Resource() {\ntry {\nThread.sleep(100);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nthis.id = System.identityHashCode(this);\n}\n\npublic long getId() {\nreturn id;\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nThread[] threads = new Thread[2];\nfor (int i = 0; i < 2; i++) {\nthreads[i] = new Thread(() -> {\nResource resource = getResource();\nSystem.out.println(\"Resource ID: \" + resource.getId() + \" from thread: \" + Thread.currentThread().getName());\n}, \"Thread-\" + i);\nthreads[i].start();\n}\nfor (int i = 0; i < 2; i++) {\nthreads[i].join();\n}\n}\n}",
        "max_depth": "47",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 2.45%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.33%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.34%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=153021,visited=140264,backtracked=292910,end=200\nsearch:             maxDepth=470,constraints=60396\nchoice generators:  thread=100688 (signal=0,lock=2398,sharedRef=76812,threadApi=1363,reschedule=7605), data=0\nheap:               new=217115,released=638473,maxLive=727,gcCycles=291245\ninstructions:       41851369\nmax memory:         1019MB\nloaded code:        classes=138,methods=2413\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 2.51%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.32%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.33%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=151525,visited=139542,backtracked=290685,end=201\nsearch:             maxDepth=470,constraints=59544\nchoice generators:  thread=99931 (signal=0,lock=2380,sharedRef=76317,threadApi=1350,reschedule=7564), data=0\nheap:               new=239278,released=298514,maxLive=725,gcCycles=289034\ninstructions:       41710720\nmax memory:         1019MB\nloaded code:        classes=138,methods=2414\n\n====================================================== search finished",
            "Unique logical threads created during execution: 11\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 5 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 6 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 7 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 8 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 9 OK (waiting proportion: 90.43%)\n[JPF-STARVATION] Thread ID: 10 OK (waiting proportion: 90.43%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=104334,visited=94442,backtracked=198306,end=0\nsearch:             maxDepth=470,constraints=162053\nchoice generators:  thread=19008 (signal=0,lock=421,sharedRef=15559,threadApi=388,reschedule=214), data=0\nheap:               new=26077,released=11986,maxLive=786,gcCycles=198776\ninstructions:       17018329\nmax memory:         1019MB\nloaded code:        classes=138,methods=2413\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            58.68,
            60.06,
            59.15
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Monitor-based vehicle tracker implementation. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe MonitorVehicleTracker class in Java that tracks the locations of vehicles using a synchronized map. The class should take an initial Map<String, MutablePoint> in its constructor and make a deep copy of it to prevent external modification. All public methods must be synchronized to ensure thread safety. Implement a getLocations() method that returns an unmodifiable deep copy of the entire map. Also provide a getLocation(String id) method that returns a new MutablePoint copy of the location for the given ID, or null if not found. Include a setLocation(String id, int x, int y) method that updates the coordinates for the specified vehicle and throws an IllegalArgumentException if the ID is not present. Use a private static deepCopy method to create a new map with copies of all MutablePoint values. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass MutablePoint {\n    public int x, y;\n    \n    public MutablePoint() {\n        x = 0;\n        y = 0;\n    }\n    \n    public MutablePoint(MutablePoint p) {\n        this.x = p.x;\n        this.y = p.y;\n    }\n    \n    public MutablePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}\n\nclass MonitorVehicleTracker {\n    private final Map<String, MutablePoint> locations;\n    \n    public MonitorVehicleTracker(Map<String, MutablePoint> locations) {\n        this.locations = deepCopy(locations);\n    }\n    \n    public synchronized Map<String, MutablePoint> getLocations() {\n        return deepCopy(locations);\n    }\n    \n    public synchronized MutablePoint getLocation(String id) {\n        MutablePoint loc = locations.get(id);\n        return loc == null ? null : new MutablePoint(loc);\n    }\n    \n    public synchronized void setLocation(String id, int x, int y) {\n        MutablePoint loc = locations.get(id);\n        if (loc == null)\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        loc.x = x;\n        loc.y = y;\n    }\n    \n    private static Map<String, MutablePoint> deepCopy(Map<String, MutablePoint> m) {\n        Map<String, MutablePoint> result = new HashMap<>();\n        for (Map.Entry<String, MutablePoint> e : m.entrySet())\n            result.put(e.getKey(), new MutablePoint(e.getValue()));\n        return Collections.unmodifiableMap(result);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutablePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new MutablePoint(10, 20));\n        initialLocations.put(\"vehicle2\", new MutablePoint(30, 40));\n        initialLocations.put(\"vehicle3\", new MutablePoint(50, 60));\n        \n        MonitorVehicleTracker tracker = new MonitorVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> writer = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                tracker.setLocation(\"vehicle2\", i * 15, i * 25);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> reader = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Map<String, MutablePoint> locations = tracker.getLocations();\n                System.out.println(\"Iteration \" + i + \":\");\n                for (Map.Entry<String, MutablePoint> entry : locations.entrySet()) {\n                    System.out.println(\"  \" + entry.getKey() + \": (\" + \n                                     entry.getValue().x + \", \" + entry.getValue().y + \")\");\n                }\n                MutablePoint v1 = tracker.getLocation(\"vehicle1\");\n                if (v1 != null) {\n                    System.out.println(\"  vehicle1 specific: (\" + v1.x + \", \" + v1.y + \")\");\n                }\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        writer.get();\n        reader.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass MutablePoint {\n    public int x, y;\n    \n    public MutablePoint() {\n        x = 0;\n        y = 0;\n    }\n    \n    public MutablePoint(MutablePoint p) {\n        this.x = p.x;\n        this.y = p.y;\n    }\n    \n    public MutablePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}\n\nclass MonitorVehicleTracker {\n    private final Map<String, MutablePoint> locations;\n    \n    public MonitorVehicleTracker(Map<String, MutablePoint> locations) {\n        this.locations = deepCopy(locations);\n    }\n    \n    public synchronized Map<String, MutablePoint> getLocations() {\n        return deepCopy(locations);\n    }\n    \n    public synchronized MutablePoint getLocation(String id) {\n        MutablePoint loc = locations.get(id);\n        return loc == null ? null : new MutablePoint(loc);\n    }\n    \n    public synchronized void setLocation(String id, int x, int y) {\n        MutablePoint loc = locations.get(id);\n        if (loc == null)\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        loc.x = x;\n        loc.y = y;\n    }\n    \n    private static Map<String, MutablePoint> deepCopy(Map<String, MutablePoint> m) {\n        Map<String, MutablePoint> result = new HashMap<>();\n        for (Map.Entry<String, MutablePoint> e : m.entrySet())\n            result.put(e.getKey(), new MutablePoint(e.getValue()));\n        return Collections.unmodifiableMap(result);\n    }\n}\n\npublic class VehicleTrackerDemo {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutablePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new MutablePoint(10, 20));\n        initialLocations.put(\"vehicle2\", new MutablePoint(30, 40));\n        initialLocations.put(\"vehicle3\", new MutablePoint(50, 60));\n        \n        MonitorVehicleTracker tracker = new MonitorVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> updater = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                    tracker.setLocation(\"vehicle2\", i * 15, i * 25);\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        Future<?> reader = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                try {\n                    MutablePoint loc1 = tracker.getLocation(\"vehicle1\");\n                    MutablePoint loc2 = tracker.getLocation(\"vehicle2\");\n                    Map<String, MutablePoint> allLocations = tracker.getLocations();\n                    System.out.println(\"Vehicle1: (\" + loc1.x + \", \" + loc1.y + \")\");\n                    System.out.println(\"Vehicle2: (\" + loc2.x + \", \" + loc2.y + \")\");\n                    System.out.println(\"Total vehicles: \" + allLocations.size());\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        updater.get();\n        reader.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass MutablePoint {\n    public int x, y;\n    \n    public MutablePoint() {\n        x = 0;\n        y = 0;\n    }\n    \n    public MutablePoint(MutablePoint p) {\n        this.x = p.x;\n        this.y = p.y;\n    }\n    \n    public MutablePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n}\n\nclass MonitorVehicleTracker {\n    private final Map<String, MutablePoint> locations;\n    \n    public MonitorVehicleTracker(Map<String, MutablePoint> locations) {\n        this.locations = deepCopy(locations);\n    }\n    \n    public synchronized Map<String, MutablePoint> getLocations() {\n        return Collections.unmodifiableMap(deepCopy(locations));\n    }\n    \n    public synchronized MutablePoint getLocation(String id) {\n        MutablePoint loc = locations.get(id);\n        return loc == null ? null : new MutablePoint(loc);\n    }\n    \n    public synchronized void setLocation(String id, int x, int y) {\n        MutablePoint loc = locations.get(id);\n        if (loc == null)\n            throw new IllegalArgumentException(\"No such ID: \" + id);\n        loc.x = x;\n        loc.y = y;\n    }\n    \n    private static Map<String, MutablePoint> deepCopy(Map<String, MutablePoint> m) {\n        Map<String, MutablePoint> result = new HashMap<>();\n        for (Map.Entry<String, MutablePoint> e : m.entrySet())\n            result.put(e.getKey(), new MutablePoint(e.getValue()));\n        return result;\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        Map<String, MutablePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new MutablePoint(10, 20));\n        initialLocations.put(\"vehicle2\", new MutablePoint(30, 40));\n        initialLocations.put(\"vehicle3\", new MutablePoint(50, 60));\n        \n        MonitorVehicleTracker tracker = new MonitorVehicleTracker(initialLocations);\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> writer = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                tracker.setLocation(\"vehicle2\", i * 15, i * 25);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        Future<?> reader = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                MutablePoint p1 = tracker.getLocation(\"vehicle1\");\n                MutablePoint p2 = tracker.getLocation(\"vehicle2\");\n                Map<String, MutablePoint> allLocations = tracker.getLocations();\n                System.out.println(\"Vehicle1: (\" + p1.x + \", \" + p1.y + \")\");\n                System.out.println(\"Vehicle2: (\" + p2.x + \", \" + p2.y + \")\");\n                System.out.println(\"Total vehicles: \" + allLocations.size());\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        writer.get();\n        reader.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\npublic class MonitorVehicleTracker {\nprivate final Map<String, MutablePoint> locations;\n\npublic MonitorVehicleTracker(Map<String, MutablePoint> locations) {\nthis.locations = deepCopy(locations);\n}\n\npublic synchronized Map<String, MutablePoint> getLocations() {\nreturn deepCopy(locations);\n}\n\npublic synchronized MutablePoint getLocation(String id) {\nMutablePoint loc = locations.get(id);\nreturn loc == null ? null : new MutablePoint(loc);\n}\n\npublic synchronized void setLocation(String id, int x, int y) {\nMutablePoint loc = locations.get(id);\nif (loc == null)\nthrow new IllegalArgumentException(\"No such ID: \" + id);\nloc.x = x;\nloc.y = y;\n}\n\nprivate static Map<String, MutablePoint> deepCopy(Map<String, MutablePoint> m) {\nMap<String, MutablePoint> result = new HashMap<>();\nfor (String id : m.keySet())\nresult.put(id, new MutablePoint(m.get(id)));\nreturn Collections.unmodifiableMap(result);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, MutablePoint> initialLocations = new HashMap<>();\ninitialLocations.put(\"car1\", new MutablePoint(0, 0));\ninitialLocations.put(\"car2\", new MutablePoint(10, 10));\n\nMonitorVehicleTracker tracker = new MonitorVehicleTracker(initialLocations);\n\nThread updater = new Thread(() -> {\ntry {\nThread.sleep(500);\ntracker.setLocation(\"car1\", 5, 5);\nSystem.out.println(\"Updated car1 to (5,5)\");\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nThread reader = new Thread(() -> {\ntry {\nThread.sleep(1000);\nMap<String, MutablePoint> snapshot = tracker.getLocations();\nSystem.out.println(\"Current locations:\");\nsnapshot.forEach((id, point) -> System.out.println(id + \": (\" + point.x + \", \" + point.y + \")\"));\n} catch (Exception e) {\ne.printStackTrace();\n}\n});\n\nupdater.start();\nreader.start();\n\nupdater.join();\nreader.join();\n\nSystem.out.println(\"All threads completed.\");\n}\n}\n\nclass MutablePoint {\npublic int x, y;\n\npublic MutablePoint() {\nthis(0, 0);\n}\n\npublic MutablePoint(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\npublic MutablePoint(MutablePoint p) {\nthis(p.x, p.y);\n}\n}",
        "max_depth": "51",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 38.95%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 21.27%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 29.50%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=128439,visited=80117,backtracked=208046,end=49196\nsearch:             maxDepth=510,constraints=6991\nchoice generators:  thread=123978 (signal=0,lock=25,sharedRef=52636,threadApi=12,reschedule=62106), data=0\nheap:               new=496793,released=3498794,maxLive=804,gcCycles=208550\ninstructions:       85390700\nmax memory:         1017MB\nloaded code:        classes=150,methods=2535\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 39.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 21.41%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 29.51%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=127316,visited=78933,backtracked=205743,end=48443\nsearch:             maxDepth=510,constraints=7551\nchoice generators:  thread=122467 (signal=0,lock=30,sharedRef=52316,threadApi=12,reschedule=61342), data=0\nheap:               new=482963,released=3463229,maxLive=804,gcCycles=206247\ninstructions:       84253343\nmax memory:         1017MB\nloaded code:        classes=151,methods=2537\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 38.95%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 21.15%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 29.57%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=129791,visited=80870,backtracked=210156,end=49684\nsearch:             maxDepth=510,constraints=7176\nchoice generators:  thread=125245 (signal=0,lock=30,sharedRef=53162,threadApi=12,reschedule=62701), data=0\nheap:               new=485848,released=3441248,maxLive=787,gcCycles=210660\ninstructions:       85609709\nmax memory:         1016MB\nloaded code:        classes=146,methods=2489\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            63.1,
            61.67,
            60.91
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Nonblocking counter using CAS. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe CasCounter class that uses a custom SimulatedCAS implementation to provide atomic increment functionality using the Compare-and-Swap (CAS) pattern. The CasCounter should have an internal SimulatedCAS field and expose two methods: getValue() which returns the current counter value, and increment() which atomically increments the value using a loop with CAS logic. The SimulatedCAS class must implement a compareAndSwap(int expected, int newValue) method that performs the swap only if the current value matches the expected one, returning the original value in both cases. The increments per thread should be no more than 2. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CasCounterDemo {\n    public static void main(String[] args) throws InterruptedException {\n        CasCounter counter = new CasCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable incrementTask = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.increment();\n            }\n        };\n        \n        executor.submit(incrementTask);\n        executor.submit(incrementTask);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final counter value: \" + counter.getValue());\n    }\n}\n\nclass CasCounter {\n    private final SimulatedCAS cas;\n    \n    public CasCounter() {\n        this.cas = new SimulatedCAS();\n    }\n    \n    public int getValue() {\n        return cas.getValue();\n    }\n    \n    public void increment() {\n        while (true) {\n            int current = cas.getValue();\n            int next = current + 1;\n            int witness = cas.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\nclass SimulatedCAS {\n    private volatile int value;\n    \n    public SimulatedCAS() {\n        this.value = 0;\n    }\n    \n    public synchronized int compareAndSwap(int expected, int newValue) {\n        int oldValue = value;\n        if (oldValue == expected) {\n            value = newValue;\n        }\n        return oldValue;\n    }\n    \n    public int getValue() {\n        return value;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CasCounterDemo {\n    public static void main(String[] args) throws InterruptedException {\n        CasCounter counter = new CasCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable incrementTask = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.increment();\n            }\n        };\n        \n        executor.submit(incrementTask);\n        executor.submit(incrementTask);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final counter value: \" + counter.getValue());\n    }\n}\n\nclass CasCounter {\n    private final SimulatedCAS cas;\n    \n    public CasCounter() {\n        this.cas = new SimulatedCAS();\n    }\n    \n    public int getValue() {\n        return cas.getValue();\n    }\n    \n    public void increment() {\n        while (true) {\n            int current = cas.getValue();\n            int next = current + 1;\n            int witness = cas.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\nclass SimulatedCAS {\n    private volatile int value;\n    \n    public SimulatedCAS() {\n        this.value = 0;\n    }\n    \n    public synchronized int compareAndSwap(int expected, int newValue) {\n        int oldValue = value;\n        if (oldValue == expected) {\n            value = newValue;\n        }\n        return oldValue;\n    }\n    \n    public int getValue() {\n        return value;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CasCounterDemo {\n    public static void main(String[] args) throws InterruptedException {\n        CasCounter counter = new CasCounter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task = () -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.increment();\n            }\n        };\n        \n        executor.submit(task);\n        executor.submit(task);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final counter value: \" + counter.getValue());\n    }\n}\n\nclass CasCounter {\n    private final SimulatedCAS cas;\n    \n    public CasCounter() {\n        this.cas = new SimulatedCAS();\n    }\n    \n    public int getValue() {\n        return cas.getValue();\n    }\n    \n    public void increment() {\n        while (true) {\n            int current = cas.getValue();\n            int next = current + 1;\n            int witness = cas.compareAndSwap(current, next);\n            if (witness == current) {\n                break;\n            }\n        }\n    }\n}\n\nclass SimulatedCAS {\n    private volatile int value;\n    \n    public SimulatedCAS() {\n        this.value = 0;\n    }\n    \n    public synchronized int compareAndSwap(int expected, int newValue) {\n        int oldValue = value;\n        if (oldValue == expected) {\n            value = newValue;\n        }\n        return oldValue;\n    }\n    \n    public int getValue() {\n        return value;\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "class SimulatedCAS {\nprivate int value;\n\npublic SimulatedCAS(int initialValue) {\nthis.value = initialValue;\n}\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized int compareAndSwap(int expectedValue, int newValue) {\nint oldValue = value;\nif (oldValue == expectedValue)\nvalue = newValue;\nreturn oldValue;\n}\n}\n\npublic class CasCounter {\nprivate final SimulatedCAS value;\n\npublic CasCounter() {\nthis.value = new SimulatedCAS(0);\n}\n\npublic int getValue() {\nreturn value.get();\n}\n\npublic int increment() {\nint v;\ndo {\nv = value.get();\n} while (v != value.compareAndSwap(v, v + 1));\nreturn v + 1;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nCasCounter counter = new CasCounter();\n\nfinal int NUM_THREADS = 2;\nfinal int INCREMENTS_PER_THREAD = 10;\n\nThread[] threads = new Thread[NUM_THREADS];\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nthreads[i] = new Thread(() -> {\nfor (int j = 0; j < INCREMENTS_PER_THREAD; j++) {\ncounter.increment();\n}\n});\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final counter value: \" + counter.getValue());\nSystem.out.println(\"Expected value: \" + (NUM_THREADS * INCREMENTS_PER_THREAD));\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nCasCounterDemo.main()\n====================================================== search started: 11/17/25 3:31 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nCasCounterDemo.main()\n====================================================== search started: 11/17/25 3:32 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nCasCounterDemo.main()\n====================================================== search started: 11/17/25 3:32 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            60.06,
            60.06,
            60.06
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Nonblocking stack using Treiber's algorithm. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class implementing a thread-safe, non-blocking stack using Treiber's algorithm. The stack should support concurrent push and pop operations without using locks. Use AtomicReference to manage the top of the stack and ensure atomicity during modifications. Include a nested static Node class to represent each element in the stack, with each node containing an item and a reference to the next node. The push method should atomically update the top of the stack to add a new node, and the pop method should remove and return the top element if the stack is not empty, also in an atomic manner using compare-and-set semantics. Provide a main method that demonstrates the functionality of the stack by creating a fixed-size thread pool and submitting multiple tasks that concurrently perform push and pop operations. Each task should push five integers onto the stack and then pop five times, printing out each operation. Ensure proper synchronization so that the main method waits for all threads to finish before printing a completion message. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.atomic.AtomicReference;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TreiberStack<T> {\n    \n    private final AtomicReference<Node<T>> top = new AtomicReference<>();\n    \n    static class Node<T> {\n        final T item;\n        final Node<T> next;\n        \n        Node(T item, Node<T> next) {\n            this.item = item;\n            this.next = next;\n        }\n    }\n    \n    public void push(T item) {\n        Node<T> newHead = new Node<>(item, null);\n        while (true) {\n            Node<T> currentHead = top.get();\n            newHead = new Node<>(item, currentHead);\n            if (top.compareAndSet(currentHead, newHead)) {\n                break;\n            }\n        }\n    }\n    \n    public T pop() {\n        while (true) {\n            Node<T> currentHead = top.get();\n            if (currentHead == null) {\n                return null;\n            }\n            Node<T> newHead = currentHead.next;\n            if (top.compareAndSet(currentHead, newHead)) {\n                return currentHead.item;\n            }\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreiberStack<Integer> stack = new TreiberStack<>();\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        Runnable task = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 1; i <= 5; i++) {\n                stack.push(i);\n                System.out.println(threadName + \" pushed: \" + i);\n            }\n            for (int i = 1; i <= 5; i++) {\n                Integer value = stack.pop();\n                System.out.println(threadName + \" popped: \" + value);\n            }\n        };\n        \n        for (int i = 0; i < 3; i++) {\n            executor.submit(task);\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"All threads completed\");\n    }\n}",
            "import java.util.concurrent.atomic.AtomicReference;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TreiberStack<T> {\n    \n    private final AtomicReference<Node<T>> top = new AtomicReference<>();\n    \n    static class Node<T> {\n        final T item;\n        final Node<T> next;\n        \n        Node(T item, Node<T> next) {\n            this.item = item;\n            this.next = next;\n        }\n    }\n    \n    public void push(T item) {\n        Node<T> newHead = new Node<>(item, null);\n        while (true) {\n            Node<T> currentHead = top.get();\n            newHead = new Node<>(item, currentHead);\n            if (top.compareAndSet(currentHead, newHead)) {\n                break;\n            }\n        }\n    }\n    \n    public T pop() {\n        while (true) {\n            Node<T> currentHead = top.get();\n            if (currentHead == null) {\n                return null;\n            }\n            Node<T> newHead = currentHead.next;\n            if (top.compareAndSet(currentHead, newHead)) {\n                return currentHead.item;\n            }\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreiberStack<Integer> stack = new TreiberStack<>();\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        Runnable task = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 1; i <= 5; i++) {\n                stack.push(i);\n                System.out.println(threadName + \" pushed: \" + i);\n            }\n            for (int i = 1; i <= 5; i++) {\n                Integer value = stack.pop();\n                System.out.println(threadName + \" popped: \" + value);\n            }\n        };\n        \n        for (int i = 0; i < 3; i++) {\n            executor.submit(task);\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"All threads completed\");\n    }\n}",
            "import java.util.concurrent.atomic.AtomicReference;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class TreiberStack<T> {\n    \n    private final AtomicReference<Node<T>> top = new AtomicReference<>();\n    \n    static class Node<T> {\n        final T item;\n        final Node<T> next;\n        \n        Node(T item, Node<T> next) {\n            this.item = item;\n            this.next = next;\n        }\n    }\n    \n    public void push(T item) {\n        Node<T> newHead = new Node<>(item, null);\n        while (true) {\n            Node<T> currentHead = top.get();\n            newHead = new Node<>(item, currentHead);\n            if (top.compareAndSet(currentHead, newHead)) {\n                break;\n            }\n        }\n    }\n    \n    public T pop() {\n        while (true) {\n            Node<T> currentHead = top.get();\n            if (currentHead == null) {\n                return null;\n            }\n            Node<T> newHead = currentHead.next;\n            if (top.compareAndSet(currentHead, newHead)) {\n                return currentHead.item;\n            }\n        }\n    }\n    \n    public static void main(String[] args) {\n        TreiberStack<Integer> stack = new TreiberStack<>();\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        Runnable task = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 1; i <= 5; i++) {\n                stack.push(i);\n                System.out.println(threadName + \" pushed: \" + i);\n            }\n            for (int i = 0; i < 5; i++) {\n                Integer value = stack.pop();\n                System.out.println(threadName + \" popped: \" + value);\n            }\n        };\n        \n        for (int i = 0; i < 3; i++) {\n            executor.submit(task);\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"All threads have completed execution\");\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.atomic.AtomicReference;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class ConcurrentStack<E> {\nprivate final AtomicReference<Node<E>> top = new AtomicReference<>();\n\npublic void push(E item) {\nNode<E> newHead = new Node<>(item);\nNode<E> oldHead;\ndo {\noldHead = top.get();\nnewHead.next = oldHead;\n} while (!top.compareAndSet(oldHead, newHead));\n}\n\npublic E pop() {\nNode<E> oldHead;\nNode<E> newHead;\ndo {\noldHead = top.get();\nif (oldHead == null)\nreturn null;\nnewHead = oldHead.next;\n} while (!top.compareAndSet(oldHead, newHead));\nreturn oldHead.item;\n}\n\nprivate static class Node<E> {\npublic final E item;\npublic Node<E> next;\n\npublic Node(E item) {\nthis.item = item;\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nConcurrentStack<Integer> stack = new ConcurrentStack<>();\n\nExecutorService executor = Executors.newFixedThreadPool(3);\n\nfor (int i = 0; i < 3; i++) {\nfinal int threadId = i;\nexecutor.submit(() -> {\nfor (int j = 0; j < 5; j++) {\nint value = threadId * 10 + j;\nstack.push(value);\nSystem.out.println(Thread.currentThread().getName() + \" pushed: \" + value);\n}\n\nfor (int j = 0; j < 5; j++) {\nInteger value = stack.pop();\nSystem.out.println(Thread.currentThread().getName() + \" popped: \" + value);\n}\n});\n}\n\nexecutor.shutdown();\nwhile (!executor.isTerminated()) {\nThread.sleep(100);\n}\n\nSystem.out.println(\"All tasks completed.\");\nSystem.out.println(\"Total threads including main: 4\");\n}\n}",
        "max_depth": "126",
        "jpf_details": [
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.33%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.37%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.38%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=161958,visited=83378,backtracked=244079,end=3\nsearch:             maxDepth=1260,constraints=130035\nchoice generators:  thread=62562 (signal=0,lock=5,sharedRef=46995,threadApi=3,reschedule=252), data=0\nheap:               new=1083204,released=450119,maxLive=994,gcCycles=245336\ninstructions:       17686411\nmax memory:         1019MB\nloaded code:        classes=138,methods=2424\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.37%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.37%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.38%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=162269,visited=82856,backtracked=243871,end=3\nsearch:             maxDepth=1260,constraints=130606\nchoice generators:  thread=62513 (signal=0,lock=5,sharedRef=46883,threadApi=3,reschedule=237), data=0\nheap:               new=1088310,released=447168,maxLive=994,gcCycles=245125\ninstructions:       17517853\nmax memory:         1019MB\nloaded code:        classes=138,methods=2424\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 74.37%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 74.38%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 74.39%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=161872,visited=82051,backtracked=242673,end=3\nsearch:             maxDepth=1260,constraints=130381\nchoice generators:  thread=62195 (signal=0,lock=5,sharedRef=46589,threadApi=3,reschedule=232), data=0\nheap:               new=1074834,released=441498,maxLive=994,gcCycles=243923\ninstructions:       17364919\nmax memory:         1018MB\nloaded code:        classes=138,methods=2424\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            59.7,
            59.7,
            60.15
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Publishing an object. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class named Secrets that contains a static Set of objects of type Secret. This set should be initialized with a new instance of HashSet in a method called initialize(). Also, define an empty class named Secret. The goal is for the knownSecrets set to be accessible globally through the Secrets class and be able to store multiple instances of the Secret class. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Secrets {\n    private static Set<Secret> knownSecrets;\n    \n    public static void initialize() {\n        knownSecrets = new HashSet<>();\n    }\n    \n    public static synchronized void addSecret(Secret secret) {\n        if (knownSecrets != null) {\n            knownSecrets.add(secret);\n        }\n    }\n    \n    public static synchronized int getSecretCount() {\n        return knownSecrets != null ? knownSecrets.size() : 0;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        initialize();\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                addSecret(new Secret());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                addSecret(new Secret());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Total secrets: \" + getSecretCount());\n    }\n}\n\nclass Secret {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Secrets {\n    private static Set<Secret> knownSecrets;\n    \n    public static void initialize() {\n        knownSecrets = new HashSet<>();\n    }\n    \n    public static synchronized void addSecret(Secret secret) {\n        knownSecrets.add(secret);\n    }\n    \n    public static synchronized Set<Secret> getKnownSecrets() {\n        return new HashSet<>(knownSecrets);\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        initialize();\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Void> task1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Secret secret = new Secret();\n                addSecret(secret);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        Future<Void> task2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Secret secret = new Secret();\n                addSecret(secret);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n            return null;\n        });\n        \n        task1.get();\n        task2.get();\n        \n        System.out.println(\"Total secrets: \" + getKnownSecrets().size());\n        \n        executor.shutdown();\n    }\n}\n\nclass Secret {\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class Secrets {\n    private static Set<Secret> knownSecrets;\n    \n    public static synchronized void initialize() {\n        knownSecrets = new HashSet<>();\n    }\n    \n    public static synchronized void addSecret(Secret secret) {\n        if (knownSecrets != null) {\n            knownSecrets.add(secret);\n        }\n    }\n    \n    public static synchronized int getSecretCount() {\n        return knownSecrets != null ? knownSecrets.size() : 0;\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<?> initTask = executor.submit(() -> {\n            initialize();\n            System.out.println(\"Initialized secrets set\");\n        });\n        \n        initTask.get();\n        \n        Future<?> addTask1 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                addSecret(new Secret());\n                System.out.println(\"Thread 1 added secret \" + (i + 1));\n            }\n        });\n        \n        Future<?> addTask2 = executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                addSecret(new Secret());\n                System.out.println(\"Thread 2 added secret \" + (i + 1));\n            }\n        });\n        \n        addTask1.get();\n        addTask2.get();\n        \n        System.out.println(\"Total secrets: \" + getSecretCount());\n        \n        executor.shutdown();\n    }\n}\n\nclass Secret {\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ConcurrentHashMap;\n\nclass Secrets {\nprivate static final Set<Secret> knownSecrets = ConcurrentHashMap.newKeySet();\n\npublic static Set<Secret> getKnownSecrets() {\nreturn knownSecrets;\n}\n}\n\nclass Secret {\nprivate final String content;\n\npublic Secret(String content) {\nthis.content = content;\n}\n\n@Override\npublic String toString() {\nreturn \"Secret{\" +\n\"content='\" + content + '\\'' +\n'}';\n}\n}\n\npublic class SecretsMain {\n\npublic static void main(String[] args) throws InterruptedException {\nThread t1 = new Thread(() -> {\nSecret secret = new Secret(\"secret-1\");\nSecrets.getKnownSecrets().add(secret);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + secret);\n});\n\nThread t2 = new Thread(() -> {\nSecret secret = new Secret(\"secret-2\");\nSecrets.getKnownSecrets().add(secret);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + secret);\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"All secrets:\");\nfor (Secret secret : Secrets.getKnownSecrets()) {\nSystem.out.println(secret);\n}\n\nSystem.out.println(\"Program finished.\");\n}\n}",
        "max_depth": "55",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 39.28%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 22.93%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 29.84%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=120771,visited=78000,backtracked=198227,end=45915\nsearch:             maxDepth=550,constraints=6078\nchoice generators:  thread=117040 (signal=0,lock=23,sharedRef=49310,threadApi=12,reschedule=59441), data=0\nheap:               new=831762,released=2499158,maxLive=759,gcCycles=198745\ninstructions:       84206201\nmax memory:         1016MB\nloaded code:        classes=141,methods=2445\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 60.97%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 60.82%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 62.18%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=130246,visited=225989,backtracked=356044,end=211\nsearch:             maxDepth=249,constraints=0\nchoice generators:  thread=130241 (signal=0,lock=15967,sharedRef=82474,threadApi=5101,reschedule=13449), data=0\nheap:               new=317027,released=177497,maxLive=760,gcCycles=342399\ninstructions:       21340937\nmax memory:         1020MB\nloaded code:        classes=141,methods=2445\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 56.26%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 59.63%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 58.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=137791,visited=219173,backtracked=356838,end=1006\nsearch:             maxDepth=188,constraints=0\nchoice generators:  thread=137759 (signal=0,lock=10150,sharedRef=99798,threadApi=1420,reschedule=5469), data=0\nheap:               new=267024,released=276498,maxLive=763,gcCycles=331071\ninstructions:       23574750\nmax memory:         1021MB\nloaded code:        classes=142,methods=2449\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            43.05,
            44.37,
            49.71
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Reducing lock duration. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a class named BetterAttributeStore that stores user attributes in a Map<String, String>, where keys follow a format like \"users.name.location\". The class should provide a method userLocationMatches(String name, String regexp) that retrieves the location attribute for a given user and checks whether it matches a regular expression using Pattern.matches(). To ensure thread safety when accessing the map, use a synchronized block on the instance (this) to read the value from the map. If the key is not present or the value is null, the method should return false. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 5. Use a fixed thread pool or manually manage at most 4 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.regex.Pattern;\n\npublic class BetterAttributeStore {\n    private final Map<String, String> attributes = new HashMap<>();\n    \n    public void setAttribute(String key, String value) {\n        synchronized (this) {\n            attributes.put(key, value);\n        }\n    }\n    \n    public boolean userLocationMatches(String name, String regexp) {\n        String key = \"users.\" + name + \".location\";\n        String value;\n        synchronized (this) {\n            value = attributes.get(key);\n        }\n        if (value == null) {\n            return false;\n        }\n        return Pattern.matches(regexp, value);\n    }\n    \n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        BetterAttributeStore store = new BetterAttributeStore();\n        ExecutorService executor = Executors.newFixedThreadPool(4);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            store.setAttribute(\"users.alice.location\", \"New York\");\n            store.setAttribute(\"users.bob.location\", \"Los Angeles\");\n            store.setAttribute(\"users.charlie.location\", \"Chicago\");\n        }));\n        \n        futures.add(executor.submit(() -> {\n            store.setAttribute(\"users.david.location\", \"Houston\");\n            store.setAttribute(\"users.eve.location\", \"Phoenix\");\n        }));\n        \n        futures.add(executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            boolean result1 = store.userLocationMatches(\"alice\", \".*York.*\");\n            boolean result2 = store.userLocationMatches(\"bob\", \".*Angeles.*\");\n            System.out.println(\"Thread 3 - Alice matches: \" + result1);\n            System.out.println(\"Thread 3 - Bob matches: \" + result2);\n        }));\n        \n        futures.add(executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            boolean result3 = store.userLocationMatches(\"charlie\", \"Chi.*\");\n            boolean result4 = store.userLocationMatches(\"nonexistent\", \".*\");\n            System.out.println(\"Thread 4 - Charlie matches: \" + result3);\n            System.out.println(\"Thread 4 - Nonexistent matches: \" + result4);\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Main thread - Final check:\");\n        System.out.println(\"Eve matches Phoenix: \" + store.userLocationMatches(\"eve\", \"Phoenix\"));\n        System.out.println(\"David matches Houston: \" + store.userLocationMatches(\"david\", \"Houston\"));\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.regex.Pattern;\n\nclass BetterAttributeStore {\n    private final Map<String, String> attributes = new HashMap<>();\n    \n    public void setAttribute(String key, String value) {\n        synchronized (this) {\n            attributes.put(key, value);\n        }\n    }\n    \n    public boolean userLocationMatches(String name, String regexp) {\n        String key = \"users.\" + name + \".location\";\n        String value;\n        synchronized (this) {\n            value = attributes.get(key);\n        }\n        if (value == null) {\n            return false;\n        }\n        return Pattern.matches(regexp, value);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        BetterAttributeStore store = new BetterAttributeStore();\n        ExecutorService executor = Executors.newFixedThreadPool(4);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            store.setAttribute(\"users.alice.location\", \"New York\");\n            store.setAttribute(\"users.bob.location\", \"Los Angeles\");\n            store.setAttribute(\"users.charlie.location\", \"Chicago\");\n        }));\n        \n        futures.add(executor.submit(() -> {\n            store.setAttribute(\"users.david.location\", \"Houston\");\n            store.setAttribute(\"users.eve.location\", \"Phoenix\");\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        List<Future<Boolean>> results = new ArrayList<>();\n        \n        results.add(executor.submit(() -> store.userLocationMatches(\"alice\", \"New.*\")));\n        results.add(executor.submit(() -> store.userLocationMatches(\"bob\", \".*Angeles\")));\n        results.add(executor.submit(() -> store.userLocationMatches(\"charlie\", \"Chi.*\")));\n        results.add(executor.submit(() -> store.userLocationMatches(\"david\", \"Houston\")));\n        results.add(executor.submit(() -> store.userLocationMatches(\"eve\", \"Phoenix\")));\n        results.add(executor.submit(() -> store.userLocationMatches(\"frank\", \".*\")));\n        \n        for (int i = 0; i < results.size(); i++) {\n            System.out.println(\"Result \" + (i + 1) + \": \" + results.get(i).get());\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.regex.Pattern;\n\nclass BetterAttributeStore {\n    private final Map<String, String> attributes = new HashMap<>();\n    \n    public void setAttribute(String key, String value) {\n        synchronized (this) {\n            attributes.put(key, value);\n        }\n    }\n    \n    public boolean userLocationMatches(String name, String regexp) {\n        String key = \"users.\" + name + \".location\";\n        String value;\n        synchronized (this) {\n            value = attributes.get(key);\n        }\n        if (value == null) {\n            return false;\n        }\n        return Pattern.matches(regexp, value);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        BetterAttributeStore store = new BetterAttributeStore();\n        ExecutorService executor = Executors.newFixedThreadPool(4);\n        \n        List<Future<?>> futures = new ArrayList<>();\n        \n        futures.add(executor.submit(() -> {\n            store.setAttribute(\"users.alice.location\", \"New York\");\n            store.setAttribute(\"users.bob.location\", \"Los Angeles\");\n            store.setAttribute(\"users.charlie.location\", \"Chicago\");\n        }));\n        \n        futures.add(executor.submit(() -> {\n            store.setAttribute(\"users.david.location\", \"Houston\");\n            store.setAttribute(\"users.eve.location\", \"Phoenix\");\n        }));\n        \n        futures.add(executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            boolean result = store.userLocationMatches(\"alice\", \"New.*\");\n            System.out.println(\"Alice location matches 'New.*': \" + result);\n        }));\n        \n        futures.add(executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            boolean result = store.userLocationMatches(\"bob\", \".*Angeles\");\n            System.out.println(\"Bob location matches '.*Angeles': \" + result);\n        }));\n        \n        for (Future<?> future : futures) {\n            future.get();\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Charlie location matches 'Chi.*': \" + store.userLocationMatches(\"charlie\", \"Chi.*\"));\n        System.out.println(\"Unknown user location matches '.*': \" + store.userLocationMatches(\"unknown\", \".*\"));\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.HashMap;\nimport java.util.Map;\n\npublic class LLMC {\nprivate final Map<String, String> attributes = new HashMap<>();\n\npublic void setAttribute(String key, String value) {\nsynchronized (this) {\nattributes.put(key, value);\n}\n}\n\npublic String getAttribute(String key) {\nsynchronized (this) {\nreturn attributes.get(key);\n}\n}\n\npublic boolean userLocationMatches(String name, String regexp) {\nString key = \"users.\" + name + \".location\";\nString location = getAttribute(key);\nif (location == null) {\nreturn false;\n}\nreturn location.matches(regexp);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal LLMC store = new LLMC();\n\nstore.setAttribute(\"users.bob.location\", \"New York\");\nstore.setAttribute(\"users.alice.location\", \"Los Angeles\");\nstore.setAttribute(\"users.charlie.location\", \"San Francisco\");\n\nRunnable task1 = () -> {\nSystem.out.println(Thread.currentThread().getName() + \": Bob in New York? \" +\nstore.userLocationMatches(\"bob\", \"New York\"));\n};\nRunnable task2 = () -> {\nSystem.out.println(Thread.currentThread().getName() + \": Alice in Los Angeles? \" +\nstore.userLocationMatches(\"alice\", \"Los Angeles\"));\n};\nRunnable task3 = () -> {\nSystem.out.println(Thread.currentThread().getName() + \": Alice in San Francisco? \" +\nstore.userLocationMatches(\"alice\", \"San Francisco\"));\n};\nRunnable task4 = () -> {\nSystem.out.println(Thread.currentThread().getName() + \": Unknown user? \" +\nstore.userLocationMatches(\"dave\", \".*\"));\n};\n\nThread t1 = new Thread(task1, \"Thread-1\");\nThread t2 = new Thread(task2, \"Thread-2\");\nThread t3 = new Thread(task3, \"Thread-3\");\nThread t4 = new Thread(task4, \"Thread-4\");\n\nt1.start();\nt2.start();\nt3.start();\nt4.start();\n\nt1.join();\nt2.join();\nt3.join();\nt4.join();\n\nSystem.out.println(\"All threads completed.\");\n}\n}",
        "max_depth": "91",
        "jpf_details": [
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.99%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 7.28%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 7.28%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 3.97%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\"\n\n====================================================== statistics\nstates:             new=151,visited=0,backtracked=0,end=0\nsearch:             maxDepth=151,constraints=0\nchoice generators:  thread=151 (signal=0,lock=13,sharedRef=123,threadApi=5,reschedule=5), data=0\nheap:               new=855,released=41,maxLive=802,gcCycles=148\ninstructions:       12982\nmax memory:         981MB\nloaded code:        classes=144,methods=2689\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.59%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 8.99%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 47.09%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 3.17%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\"\n\n====================================================== statistics\nstates:             new=189,visited=0,backtracked=0,end=0\nsearch:             maxDepth=189,constraints=0\nchoice generators:  thread=189 (signal=0,lock=15,sharedRef=163,threadApi=4,reschedule=1), data=0\nheap:               new=934,released=71,maxLive=851,gcCycles=183\ninstructions:       17107\nmax memory:         981MB\nloaded code:        classes=145,methods=2698\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.99%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 7.28%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 7.28%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 3.97%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\"\n\n====================================================== statistics\nstates:             new=151,visited=0,backtracked=0,end=0\nsearch:             maxDepth=151,constraints=0\nchoice generators:  thread=151 (signal=0,lock=13,sharedRef=123,threadApi=5,reschedule=5), data=0\nheap:               new=858,released=41,maxLive=805,gcCycles=148\ninstructions:       12982\nmax memory:         981MB\nloaded code:        classes=145,methods=2690\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.util.concurrent.ExecutionException: java.lang...\""
        ],
        "codebleu_score": [
            56.5,
            51.06,
            55.44
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Returning a static copy of the location set instead of a 'live' one. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called DelegatingVehicleTracker that manages the locations of vehicles in a thread-safe manner using a ConcurrentHashMap. The class should provide methods to get the location of a specific vehicle, set the location of a vehicle, and return an unmodifiable view of all vehicle locations. Use delegation to ensure thread safety without explicitly synchronizing methods. Initialize the tracker with a map of vehicle IDs to their initial locations. Include two versions of the method to retrieve all locations: one that returns a live unmodifiable map backed by the original data, and another that returns a static snapshot of the current state as an unmodifiable map. Ensure that updating a vehicle's location only succeeds if the vehicle ID already exists in the map. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingVehicleTracker {\n    private final ConcurrentHashMap<String, Point> locations;\n    private final Map<String, Point> unmodifiableMap;\n\n    public DelegatingVehicleTracker(Map<String, Point> points) {\n        locations = new ConcurrentHashMap<>(points);\n        unmodifiableMap = Collections.unmodifiableMap(locations);\n    }\n\n    public Map<String, Point> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public Map<String, Point> getLocationsAsStatic() {\n        return Collections.unmodifiableMap(\n            new HashMap<>(locations));\n    }\n\n    public Point getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public boolean setLocation(String id, int x, int y) {\n        if (locations.containsKey(id)) {\n            locations.put(id, new Point(x, y));\n            return true;\n        }\n        return false;\n    }\n\n    public static void main(String[] args) {\n        // Initialize tracker with some vehicles\n        Map<String, Point> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new Point(0, 0));\n        initialLocations.put(\"vehicle2\", new Point(10, 10));\n        initialLocations.put(\"vehicle3\", new Point(20, 20));\n        \n        DelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n        \n        System.out.println(\"Initial locations:\");\n        printLocations(tracker.getLocations());\n        \n        // Create a fixed thread pool with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Task 1: Continuously update vehicle1's location\n        Runnable updateTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                int newX = (int)(Math.random() * 100);\n                int newY = (int)(Math.random() * 100);\n                boolean updated = tracker.setLocation(\"vehicle1\", newX, newY);\n                System.out.println(threadName + \" - Updated vehicle1 to (\" + \n                                 newX + \", \" + newY + \"): \" + updated);\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Task 2: Read and display locations\n        Runnable readTask = () -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 5; i++) {\n                Point location = tracker.getLocation(\"vehicle1\");\n                System.out.println(threadName + \" - Read vehicle1 location: \" + location);\n                \n                // Test static snapshot vs live view\n                if (i == 2) {\n                    System.out.println(threadName + \" - Getting snapshots:\");\n                    Map<String, Point> liveView = tracker.getLocations();\n                    Map<String, Point> staticSnapshot = tracker.getLocationsAsStatic();\n                    \n                    System.out.println(\"  Live view size: \" + liveView.size());\n                    System.out.println(\"  Static snapshot size: \" + staticSnapshot.size());\n                }\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        };\n        \n        // Submit tasks to executor\n        Future<?> updateFuture = executor.submit(updateTask);\n        Future<?> readFuture = executor.submit(readTask);\n        \n        // Main thread also performs some operations\n        System.out.println(\"\\nMain thread operations:\");\n        for (int i = 0; i < 3; i++) {\n            boolean updated = tracker.setLocation(\"vehicle2\", i * 5, i * 5);\n            System.out.println(\"Main - Updated vehicle2 to (\" + \n                             (i * 5) + \", \" + (i * 5) + \"): \" + updated);\n            \n            // Try to update non-existent vehicle\n            boolean failedUpdate = tracker.setLocation(\"vehicle99\", 50, 50);\n            System.out.println(\"Main - Attempted to update non-existent vehicle99: \" + failedUpdate);\n            \n            try {\n                Thread.sleep(200);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                break;\n            }\n        }\n        \n        // Wait for tasks to complete\n        try {\n            updateFuture.get(3, TimeUnit.SECONDS);\n            readFuture.get(3, TimeUnit.SECONDS);\n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            System.err.println(\"Error waiting for tasks: \" + e.getMessage());\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        System.out.println(\"\\nFinal locations:\");\n        printLocations(tracker.getLocations());\n        \n        // Demonstrate difference between live view and static snapshot\n        System.out.println(\"\\nDemonstrating live view vs static snapshot:\");\n        Map<String, Point> liveView = tracker.getLocations();\n        Map<String, Point> staticSnapshot = tracker.getLocationsAsStatic();\n        \n        System.out.println(\"Before update:\");\n        System.out.println(\"  vehicle3 in live view: \" + liveView.get(\"vehicle3\"));\n        System.out.println(\"  vehicle3 in static snapshot: \" + staticSnapshot.get(\"vehicle3\"));\n        \n        tracker.setLocation(\"vehicle3\", 99, 99);\n        \n        System.out.println(\"After update:\");\n        System.out.println(\"  vehicle3 in live view: \" + liveView.get(\"vehicle3\"));\n        System.out.println(\"  vehicle3 in static snapshot: \" + staticSnapshot.get(\"vehicle3\"));\n        \n        // Test immutability\n        System.out.println(\"\\nTesting immutability:\");\n        try {\n            liveView.put(\"newVehicle\", new Point(0, 0));\n            System.out.println(\"ERROR: Live view should be unmodifiable!\");\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Live view is correctly unmodifiable\");\n        }\n        \n        try {\n            staticSnapshot.put(\"newVehicle\", new Point(0, 0));\n            System.out.println(\"ERROR: Static snapshot should be unmodifiable!\");\n        } catch (UnsupportedOperationException e) {\n            System.out.println(\"Static snapshot is correctly unmodifiable\");\n        }\n    }\n    \n    private static void printLocations(Map<String, Point> locations) {\n        for (Map.Entry<String, Point> entry : locations.entrySet()) {\n            System.out.println(\"  \" + entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass Point {\n    private final int x;\n    private final int y;\n    \n    public Point(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public int getX() {\n        return x;\n    }\n    \n    public int getY() {\n        return y;\n    }\n    \n    public String toString() {\n        return \"(\" + x + \", \" + y + \")\";\n    }\n    \n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        Point point = (Point) obj;\n        return x == point.x && y == point.y;\n    }\n    \n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingVehicleTracker {\n    private final ConcurrentMap<String, Point> locations;\n    private final Map<String, Point> unmodifiableMap;\n\n    public DelegatingVehicleTracker(Map<String, Point> points) {\n        this.locations = new ConcurrentHashMap<>(points);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    // Get location of a specific vehicle\n    public Point getLocation(String id) {\n        Point loc = locations.get(id);\n        return loc == null ? null : new Point(loc);\n    }\n\n    // Set location of a vehicle (only if vehicle ID exists)\n    public boolean setLocation(String id, int x, int y) {\n        if (locations.containsKey(id)) {\n            locations.put(id, new Point(x, y));\n            return true;\n        }\n        return false;\n    }\n\n    // Returns a live unmodifiable view backed by the original data\n    public Map<String, Point> getLocationsLive() {\n        return unmodifiableMap;\n    }\n\n    // Returns a static snapshot of the current state as an unmodifiable map\n    public Map<String, Point> getLocationsSnapshot() {\n        Map<String, Point> snapshot = new HashMap<>();\n        for (Map.Entry<String, Point> entry : locations.entrySet()) {\n            snapshot.put(entry.getKey(), new Point(entry.getValue()));\n        }\n        return Collections.unmodifiableMap(snapshot);\n    }\n\n    public static void main(String[] args) {\n        // Initialize with some vehicles\n        Map<String, Point> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new Point(10, 20));\n        initialLocations.put(\"vehicle2\", new Point(30, 40));\n        initialLocations.put(\"vehicle3\", new Point(50, 60));\n        \n        DelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n        \n        // Create a fixed thread pool with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Thread 1: Continuously update vehicle locations\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            Random random = new Random();\n            for (int i = 0; i < 10; i++) {\n                String vehicleId = \"vehicle\" + (random.nextInt(3) + 1);\n                int newX = random.nextInt(100);\n                int newY = random.nextInt(100);\n                \n                boolean updated = tracker.setLocation(vehicleId, newX, newY);\n                if (updated) {\n                    System.out.println(\"[\" + threadName + \"] Updated \" + vehicleId + \n                                     \" to position (\" + newX + \", \" + newY + \")\");\n                }\n                \n                // Try to update a non-existent vehicle (should fail)\n                boolean failedUpdate = tracker.setLocation(\"vehicle99\", 0, 0);\n                if (!failedUpdate && i == 0) {\n                    System.out.println(\"[\" + threadName + \"] Failed to update non-existent vehicle99 (expected)\");\n                }\n                \n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        // Thread 2: Continuously read vehicle locations\n        executor.submit(() -> {\n            String threadName = Thread.currentThread().getName();\n            for (int i = 0; i < 10; i++) {\n                // Get specific vehicle location\n                Point vehicle1Loc = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"[\" + threadName + \"] Vehicle1 location: \" + vehicle1Loc);\n                \n                // Get live view (changes will be reflected)\n                Map<String, Point> liveView = tracker.getLocationsLive();\n                System.out.println(\"[\" + threadName + \"] Live view size: \" + liveView.size());\n                \n                // Get snapshot (frozen state)\n                Map<String, Point> snapshot = tracker.getLocationsSnapshot();\n                System.out.println(\"[\" + threadName + \"] Snapshot: \" + snapshot);\n                \n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        // Main thread: Demonstrate the difference between live view and snapshot\n        try {\n            Thread.sleep(500);\n            \n            System.out.println(\"\\n[Main Thread] Demonstrating live view vs snapshot:\");\n            Map<String, Point> liveView = tracker.getLocationsLive();\n            Map<String, Point> snapshot = tracker.getLocationsSnapshot();\n            \n            System.out.println(\"[Main Thread] Initial live view: \" + liveView);\n            System.out.println(\"[Main Thread] Initial snapshot: \" + snapshot);\n            \n            // Update a location\n            tracker.setLocation(\"vehicle1\", 999, 999);\n            \n            System.out.println(\"[Main Thread] After update:\");\n            System.out.println(\"[Main Thread] Live view (should show update): \" + liveView);\n            System.out.println(\"[Main Thread] Snapshot (should NOT show update): \" + snapshot);\n            \n            // Try to modify the unmodifiable maps (will throw exception)\n            try {\n                liveView.put(\"newVehicle\", new Point(0, 0));\n            } catch (UnsupportedOperationException e) {\n                System.out.println(\"[Main Thread] Cannot modify live view (expected)\");\n            }\n            \n            try {\n                snapshot.put(\"newVehicle\", new Point(0, 0));\n            } catch (UnsupportedOperationException e) {\n                System.out.println(\"[Main Thread] Cannot modify snapshot (expected)\");\n            }\n            \n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(2, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"\\n[Main Thread] Final state of all vehicles:\");\n        Map<String, Point> finalSnapshot = tracker.getLocationsSnapshot();\n        for (Map.Entry<String, Point> entry : finalSnapshot.entrySet()) {\n            System.out.println(\"  \" + entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass Point {\n    private final int x;\n    private final int y;\n    \n    public Point(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public Point(Point p) {\n        this.x = p.x;\n        this.y = p.y;\n    }\n    \n    public int getX() {\n        return x;\n    }\n    \n    public int getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return \"(\" + x + \", \" + y + \")\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Point point = (Point) o;\n        return x == point.x && y == point.y;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class DelegatingVehicleTracker {\n    private final ConcurrentMap<String, Point> locations;\n    private final Map<String, Point> unmodifiableMap;\n\n    public DelegatingVehicleTracker(Map<String, Point> points) {\n        locations = new ConcurrentHashMap<>(points);\n        unmodifiableMap = Collections.unmodifiableMap(locations);\n    }\n\n    public Map<String, Point> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public Map<String, Point> getLocationsAsStatic() {\n        return Collections.unmodifiableMap(\n            new HashMap<>(locations));\n    }\n\n    public Point getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public boolean setLocation(String id, int x, int y) {\n        if (locations.replace(id, new Point(x, y)) == null) {\n            return false;\n        }\n        return true;\n    }\n\n    public static void main(String[] args) {\n        // Initialize tracker with some vehicles\n        Map<String, Point> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new Point(0, 0));\n        initialLocations.put(\"vehicle2\", new Point(10, 20));\n        initialLocations.put(\"vehicle3\", new Point(30, 40));\n        \n        DelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialLocations);\n        \n        // Create executor service with 2 threads (plus main thread = 3 total)\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        // Create concurrent tasks\n        Runnable updater1 = new VehicleUpdater(tracker, \"vehicle1\", 1);\n        Runnable updater2 = new VehicleUpdater(tracker, \"vehicle2\", 2);\n        \n        // Submit tasks\n        Future<?> future1 = executor.submit(updater1);\n        Future<?> future2 = executor.submit(updater2);\n        \n        // Main thread also performs some operations\n        System.out.println(\"Initial locations (live view): \" + tracker.getLocations());\n        System.out.println(\"Initial locations (static snapshot): \" + tracker.getLocationsAsStatic());\n        \n        // Main thread updates vehicle3\n        for (int i = 0; i < 5; i++) {\n            tracker.setLocation(\"vehicle3\", 100 + i * 10, 200 + i * 10);\n            System.out.println(\"Main thread updated vehicle3 to: \" + tracker.getLocation(\"vehicle3\"));\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        // Try to update non-existent vehicle\n        boolean success = tracker.setLocation(\"vehicle4\", 500, 600);\n        System.out.println(\"Attempt to update non-existent vehicle4: \" + (success ? \"Success\" : \"Failed\"));\n        \n        // Wait for tasks to complete\n        try {\n            future1.get();\n            future2.get();\n        } catch (InterruptedException | ExecutionException e) {\n            e.printStackTrace();\n        }\n        \n        // Shutdown executor\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n        }\n        \n        // Display final state\n        System.out.println(\"\\nFinal locations:\");\n        Map<String, Point> finalLocations = tracker.getLocations();\n        for (Map.Entry<String, Point> entry : finalLocations.entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n        \n        // Demonstrate difference between live view and static snapshot\n        System.out.println(\"\\nDemonstrating live view vs static snapshot:\");\n        Map<String, Point> liveView = tracker.getLocations();\n        Map<String, Point> staticSnapshot = tracker.getLocationsAsStatic();\n        \n        System.out.println(\"Before update - Live view vehicle1: \" + liveView.get(\"vehicle1\"));\n        System.out.println(\"Before update - Static snapshot vehicle1: \" + staticSnapshot.get(\"vehicle1\"));\n        \n        tracker.setLocation(\"vehicle1\", 999, 999);\n        \n        System.out.println(\"After update - Live view vehicle1: \" + liveView.get(\"vehicle1\"));\n        System.out.println(\"After update - Static snapshot vehicle1: \" + staticSnapshot.get(\"vehicle1\"));\n    }\n}\n\nclass Point {\n    private final int x;\n    private final int y;\n    \n    public Point(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public int getX() {\n        return x;\n    }\n    \n    public int getY() {\n        return y;\n    }\n    \n    @Override\n    public String toString() {\n        return \"Point[x=\" + x + \", y=\" + y + \"]\";\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        Point point = (Point) o;\n        return x == point.x && y == point.y;\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(x, y);\n    }\n}\n\nclass VehicleUpdater implements Runnable {\n    private final DelegatingVehicleTracker tracker;\n    private final String vehicleId;\n    private final int threadId;\n    \n    public VehicleUpdater(DelegatingVehicleTracker tracker, String vehicleId, int threadId) {\n        this.tracker = tracker;\n        this.vehicleId = vehicleId;\n        this.threadId = threadId;\n    }\n    \n    @Override\n    public void run() {\n        for (int i = 0; i < 10; i++) {\n            int newX = threadId * 100 + i;\n            int newY = threadId * 200 + i;\n            boolean updated = tracker.setLocation(vehicleId, newX, newY);\n            \n            if (updated) {\n                System.out.println(\"Thread \" + threadId + \" updated \" + vehicleId + \n                                 \" to: \" + tracker.getLocation(vehicleId));\n            } else {\n                System.out.println(\"Thread \" + threadId + \" failed to update \" + vehicleId);\n            }\n            \n            try {\n                Thread.sleep(50);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n                return;\n            }\n        }\n        System.out.println(\"Thread \" + threadId + \" completed updates for \" + vehicleId);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.awt.Point;\nimport java.util.*;\nimport java.util.concurrent.*;\n\n/**\n* DelegatingVehicleTracker\n* Delegates thread safety to a ConcurrentHashMap.\n*/\npublic class DelegatingVehicleTracker {\n\nprivate final ConcurrentMap<String, Point> locations;\nprivate final Map<String, Point> unmodifiableMap;\n\npublic DelegatingVehicleTracker(Map<String, Point> points) {\nlocations = new ConcurrentHashMap<>(points);\nunmodifiableMap = Collections.unmodifiableMap(locations);\n}\n\npublic Map<String, Point> getLocations() {\nreturn unmodifiableMap;\n}\n\n\npublic void setLocation(String id, int x, int y) {\nif (locations.replace(id, new Point(x, y)) == null)\nthrow new IllegalArgumentException(\"Invalid vehicle name: \" + id);\n}\n\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, Point> initialVehicles = new HashMap<>();\ninitialVehicles.put(\"V1\", new Point(0, 0));\ninitialVehicles.put(\"V2\", new Point(0, 0));\ninitialVehicles.put(\"V3\", new Point(0, 0));\n\nDelegatingVehicleTracker tracker = new DelegatingVehicleTracker(initialVehicles);\n\n// Reduce threads to 2 for JPF-friendly execution\nThread[] threads = new Thread[2];\n\nfor (int i = 0; i < 2; i++) {\nfinal String vehicleId = \"V\" + ((i % 3) + 1);\nthreads[i] = new Thread(() -> {\ntry {\n// Reduce iterations to 2 per thread\nfor (int j = 0; j < 2; j++) {\n// Use deterministic fixed values instead of random\nint x = j * 10 + 5;\nint y = j * 20 + 5;\ntracker.setLocation(vehicleId, x, y);\nSystem.out.println(Thread.currentThread().getName() +\n\" updated \" + vehicleId + \" to (\" + x + \", \" + y + \")\");\nThread.sleep(10);\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\ntracker.getLocations().forEach((id, point) ->\nSystem.out.println(id + \": (\" + point.x + \", \" + point.y + \")\"));\n}\n}",
        "max_depth": "57",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 52.74%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.52%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.51%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=134685,visited=133072,backtracked=267187,end=0\nsearch:             maxDepth=570,constraints=80845\nchoice generators:  thread=89631 (signal=0,lock=79,sharedRef=83565,threadApi=80,reschedule=0), data=0\nheap:               new=549971,released=109157,maxLive=897,gcCycles=259068\ninstructions:       20946841\nmax memory:         1020MB\nloaded code:        classes=164,methods=2722\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.47%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.89%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.90%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=86199,visited=116606,backtracked=202417,end=187\nsearch:             maxDepth=570,constraints=18785\nchoice generators:  thread=70007 (signal=0,lock=17,sharedRef=59697,threadApi=3,reschedule=6059), data=0\nheap:               new=415465,released=286472,maxLive=899,gcCycles=196152\ninstructions:       72181716\nmax memory:         1019MB\nloaded code:        classes=165,methods=2797\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 40.87%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 25.96%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 32.76%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=49061,visited=34509,backtracked=83181,end=17149\nsearch:             maxDepth=570,constraints=2443\nchoice generators:  thread=47429 (signal=0,lock=25,sharedRef=19477,threadApi=17,reschedule=25110), data=0\nheap:               new=2356109,released=2878444,maxLive=899,gcCycles=83307\ninstructions:       110209445\nmax memory:         1008MB\nloaded code:        classes=164,methods=2774\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            62.22,
            59.75,
            61.3
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "ServerStatus refactored to use split locks. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a class named ServerStatusAfterSplit that maintains two sets of strings: one for users and one for queries. Both sets should be initialized in the constructor using HashSet<String>. To improve concurrency performance, each method that modifies a set should synchronize on the corresponding collection object (users or queries) rather than the entire instance. This allows multiple threads to modify different sets concurrently without blocking each other. Implement four methods: addUser(String u), addQuery(String q), removeUser(String u), and removeQuery(String q), each of which performs the appropriate operation on its respective set while holding the lock on that specific collection. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusAfterSplit {\n    private final Set<String> users;\n    private final Set<String> queries;\n    \n    public ServerStatusAfterSplit() {\n        this.users = new HashSet<String>();\n        this.queries = new HashSet<String>();\n    }\n    \n    public void addUser(String u) {\n        synchronized(users) {\n            users.add(u);\n        }\n    }\n    \n    public void addQuery(String q) {\n        synchronized(queries) {\n            queries.add(q);\n        }\n    }\n    \n    public void removeUser(String u) {\n        synchronized(users) {\n            users.remove(u);\n        }\n    }\n    \n    public void removeQuery(String q) {\n        synchronized(queries) {\n            queries.remove(q);\n        }\n    }\n    \n    public int getUserCount() {\n        synchronized(users) {\n            return users.size();\n        }\n    }\n    \n    public int getQueryCount() {\n        synchronized(queries) {\n            return queries.size();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusAfterSplit server = new ServerStatusAfterSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                if (i % 2 == 0) {\n                    server.removeUser(\"user\" + (i / 2));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addQuery(\"query\" + i);\n                if (i % 3 == 0) {\n                    server.removeQuery(\"query\" + (i / 3));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Users: \" + server.getUserCount());\n        System.out.println(\"Queries: \" + server.getQueryCount());\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusAfterSplit {\n    private final Set<String> users;\n    private final Set<String> queries;\n    \n    public ServerStatusAfterSplit() {\n        this.users = new HashSet<String>();\n        this.queries = new HashSet<String>();\n    }\n    \n    public void addUser(String u) {\n        synchronized (users) {\n            users.add(u);\n        }\n    }\n    \n    public void addQuery(String q) {\n        synchronized (queries) {\n            queries.add(q);\n        }\n    }\n    \n    public void removeUser(String u) {\n        synchronized (users) {\n            users.remove(u);\n        }\n    }\n    \n    public void removeQuery(String q) {\n        synchronized (queries) {\n            queries.remove(q);\n        }\n    }\n    \n    public int getUserCount() {\n        synchronized (users) {\n            return users.size();\n        }\n    }\n    \n    public int getQueryCount() {\n        synchronized (queries) {\n            return queries.size();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusAfterSplit server = new ServerStatusAfterSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"user\" + (i - 1));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addQuery(\"query\" + i);\n                if (i % 4 == 0) {\n                    server.removeQuery(\"query\" + (i - 2));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Users: \" + server.getUserCount());\n        System.out.println(\"Queries: \" + server.getQueryCount());\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\nclass ServerStatusAfterSplit {\n    private final Set<String> users;\n    private final Set<String> queries;\n    \n    public ServerStatusAfterSplit() {\n        this.users = new HashSet<String>();\n        this.queries = new HashSet<String>();\n    }\n    \n    public void addUser(String u) {\n        synchronized(users) {\n            users.add(u);\n        }\n    }\n    \n    public void addQuery(String q) {\n        synchronized(queries) {\n            queries.add(q);\n        }\n    }\n    \n    public void removeUser(String u) {\n        synchronized(users) {\n            users.remove(u);\n        }\n    }\n    \n    public void removeQuery(String q) {\n        synchronized(queries) {\n            queries.remove(q);\n        }\n    }\n    \n    public int getUserCount() {\n        synchronized(users) {\n            return users.size();\n        }\n    }\n    \n    public int getQueryCount() {\n        synchronized(queries) {\n            return queries.size();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        ServerStatusAfterSplit server = new ServerStatusAfterSplit();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addUser(\"user\" + i);\n                if (i % 3 == 0) {\n                    server.removeUser(\"user\" + (i - 1));\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 100; i++) {\n                server.addQuery(\"query\" + i);\n                if (i % 2 == 0) {\n                    server.removeQuery(\"query\" + (i - 1));\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Users: \" + server.getUserCount());\n        System.out.println(\"Queries: \" + server.getQueryCount());\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "import java.util.HashSet;\nimport java.util.Set;\n\npublic class ServerStatusAfterSplit {\npublic final Set<String> users;\npublic final Set<String> queries;\n\npublic ServerStatusAfterSplit() {\nusers = new HashSet<>();\nqueries = new HashSet<>();\n}\n\npublic void addUser(String u) {\nsynchronized (users) {\nusers.add(u);\n}\n}\n\npublic void addQuery(String q) {\nsynchronized (queries) {\nqueries.add(q);\n}\n}\n\npublic void removeUser(String u) {\nsynchronized (users) {\nusers.remove(u);\n}\n}\n\npublic void removeQuery(String q) {\nsynchronized (queries) {\nqueries.remove(q);\n}\n}\n\npublic Set<String> getActiveUsers() {\nsynchronized (users) {\nreturn new HashSet<>(users);\n}\n}\n\npublic Set<String> getActiveQueries() {\nsynchronized (queries) {\nreturn new HashSet<>(queries);\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nServerStatusAfterSplit status = new ServerStatusAfterSplit();\n\nThread t1 = new Thread(() -> {\nstatus.addUser(\"user1\");\nstatus.addQuery(\"query1\");\ntry {\nThread.sleep(500);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user1\");\nstatus.removeQuery(\"query1\");\n});\n\nThread t2 = new Thread(() -> {\nstatus.addUser(\"user2\");\nstatus.addQuery(\"query2\");\ntry {\nThread.sleep(300);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\nstatus.removeUser(\"user2\");\nstatus.removeQuery(\"query2\");\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nSystem.out.println(\"Final active users: \" + status.getActiveUsers());\nSystem.out.println(\"Final active queries: \" + status.getActiveQueries());\n}\n}",
        "max_depth": "17",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/17/25 3:36 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/17/25 3:36 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/17/25 3:36 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            57.01,
            57.01,
            57.01
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Simple thread-safe counter using the Java monitor pattern. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a thread-safe Counter class in Java using the monitor pattern, where all methods are synchronized to ensure safe access from multiple threads. The class should have a private long field named value initialized to 0. It must provide two synchronized methods: getValue() returns the current value, and increment() increases the value by one and returns it. If the value is already at Long.MAX_VALUE, increment() should throw an IllegalStateException with the message \"counter overflow\". Keep the implementation simple and avoid any external annotations or dependencies. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        Counter counter = new Counter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 1000; i++) {\n                try {\n                    counter.increment();\n                } catch (IllegalStateException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                    break;\n                }\n            }\n            System.out.println(\"Thread 1 final value: \" + counter.getValue());\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 1000; i++) {\n                try {\n                    counter.increment();\n                } catch (IllegalStateException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                    break;\n                }\n            }\n            System.out.println(\"Thread 2 final value: \" + counter.getValue());\n        };\n        \n        executor.submit(task1);\n        executor.submit(task2);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final counter value: \" + counter.getValue());\n    }\n}\n\nclass Counter {\n    private long value = 0;\n    \n    public synchronized long getValue() {\n        return value;\n    }\n    \n    public synchronized long increment() {\n        if (value == Long.MAX_VALUE) {\n            throw new IllegalStateException(\"counter overflow\");\n        }\n        value++;\n        return value;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class CounterDemo {\n    public static void main(String[] args) throws InterruptedException {\n        Counter counter = new Counter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 1000; i++) {\n                try {\n                    counter.increment();\n                } catch (IllegalStateException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                    break;\n                }\n            }\n            System.out.println(\"Thread 1 final value: \" + counter.getValue());\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 1000; i++) {\n                try {\n                    counter.increment();\n                } catch (IllegalStateException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                    break;\n                }\n            }\n            System.out.println(\"Thread 2 final value: \" + counter.getValue());\n        };\n        \n        executor.submit(task1);\n        executor.submit(task2);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final counter value: \" + counter.getValue());\n    }\n}\n\nclass Counter {\n    private long value = 0;\n    \n    public synchronized long getValue() {\n        return value;\n    }\n    \n    public synchronized long increment() {\n        if (value == Long.MAX_VALUE) {\n            throw new IllegalStateException(\"counter overflow\");\n        }\n        value++;\n        return value;\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        Counter counter = new Counter();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 1000; i++) {\n                try {\n                    counter.increment();\n                } catch (IllegalStateException e) {\n                    System.out.println(\"Thread 1: \" + e.getMessage());\n                    break;\n                }\n            }\n            System.out.println(\"Thread 1 final value: \" + counter.getValue());\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 1000; i++) {\n                try {\n                    counter.increment();\n                } catch (IllegalStateException e) {\n                    System.out.println(\"Thread 2: \" + e.getMessage());\n                    break;\n                }\n            }\n            System.out.println(\"Thread 2 final value: \" + counter.getValue());\n        };\n        \n        executor.submit(task1);\n        executor.submit(task2);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final counter value: \" + counter.getValue());\n    }\n}\n\nclass Counter {\n    private long value = 0;\n    \n    public synchronized long getValue() {\n        return value;\n    }\n    \n    public synchronized long increment() {\n        if (value == Long.MAX_VALUE) {\n            throw new IllegalStateException(\"counter overflow\");\n        }\n        value++;\n        return value;\n    }\n}"
        ],
        "graded_list": [
            false,
            false,
            false
        ],
        "ground_truth": "public final class Counter {\nprivate long value = 0;\n\npublic synchronized long getValue() {\nreturn value;\n}\n\npublic synchronized long increment() {\nif (value == Long.MAX_VALUE)\nthrow new IllegalStateException(\"counter overflow\");\nreturn ++value;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal int NUM_THREADS = 2; \nfinal int INCREMENTS_PER_THREAD = 10; \nfinal Counter counter = new Counter();\n\nThread[] threads = new Thread[NUM_THREADS];\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nthreads[i] = new Thread(() -> {\nfor (int j = 0; j < INCREMENTS_PER_THREAD; j++) {\ncounter.increment();\n}\n});\nthreads[i].start();\n}\n\nfor (Thread thread : threads) {\nthread.join();\n}\n\nSystem.out.println(\"Final counter value: \" + counter.getValue());\nSystem.out.println(\"Expected value: \" + (NUM_THREADS * INCREMENTS_PER_THREAD));\n}\n}",
        "max_depth": "130",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/17/25 3:36 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nCounterDemo.main()\n====================================================== search started: 11/17/25 3:37 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nMain.main()\n====================================================== search started: 11/17/25 3:37 PM\n====================================================== search constraint\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            51.08,
            51.08,
            51.08
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.0
    },
    {
        "prompt_title": "Simulated CAS operation. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class called SimulatedCAS that simulates the behavior of a Compare-and-Swap (CAS) operation, which is commonly used in concurrent programming for atomic updates. The class should maintain an internal integer value and provide thread-safe methods to interact with it.\n\nThe class should include:\n\nA private integer field value to store the current value.\nA synchronized get() method that returns the current value.\nA synchronized compareAndSwap(int expectedValue, int newValue) method that checks if the current value matches the expectedValue. If it does, it updates the value to newValue; otherwise, it leaves the value unchanged. This method should return the original (old) value before any potential update.\nA synchronized compareAndSet(int expectedValue, int newValue) method that uses compareAndSwap() to determine whether the value was successfully updated. It should return true if the value was changed (i.e., if the old value matched the expected value), and false otherwise.\nEnsure that all methods are thread-safe using the synchronized keyword to prevent race conditions when accessed by multiple threads concurrently. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SimulatedCAS {\n    private int value;\n    \n    public SimulatedCAS(int initialValue) {\n        this.value = initialValue;\n    }\n    \n    public synchronized int get() {\n        return value;\n    }\n    \n    public synchronized int compareAndSwap(int expectedValue, int newValue) {\n        int oldValue = value;\n        if (oldValue == expectedValue) {\n            value = newValue;\n        }\n        return oldValue;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedValue, int newValue) {\n        return compareAndSwap(expectedValue, newValue) == expectedValue;\n    }\n    \n    public static void main(String[] args) {\n        SimulatedCAS cas = new SimulatedCAS(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = cas.get();\n                boolean success = cas.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: \" + current + \" -> \" + (current + 1) + \", success: \" + success);\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = cas.get();\n                boolean success = cas.compareAndSet(current, current + 10);\n                System.out.println(\"Thread 2: \" + current + \" -> \" + (current + 10) + \", success: \" + success);\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        \n        for (int i = 0; i < 5; i++) {\n            int current = cas.get();\n            int oldValue = cas.compareAndSwap(current, current + 100);\n            System.out.println(\"Main thread: old value: \" + oldValue + \", new value: \" + cas.get());\n            try {\n                Thread.sleep(20);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final value: \" + cas.get());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SimulatedCAS {\n    private int value;\n    \n    public SimulatedCAS(int initialValue) {\n        this.value = initialValue;\n    }\n    \n    public synchronized int get() {\n        return value;\n    }\n    \n    public synchronized int compareAndSwap(int expectedValue, int newValue) {\n        int oldValue = value;\n        if (oldValue == expectedValue) {\n            value = newValue;\n        }\n        return oldValue;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedValue, int newValue) {\n        return compareAndSwap(expectedValue, newValue) == expectedValue;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        SimulatedCAS cas = new SimulatedCAS(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        Runnable task1 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = cas.get();\n                boolean success = cas.compareAndSet(current, current + 1);\n                System.out.println(\"Thread 1: \" + (success ? \"Updated\" : \"Failed\") + \" from \" + current + \" to \" + (current + 1));\n                try {\n                    Thread.sleep(10);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        Runnable task2 = () -> {\n            for (int i = 0; i < 5; i++) {\n                int current = cas.get();\n                boolean success = cas.compareAndSet(current, current + 10);\n                System.out.println(\"Thread 2: \" + (success ? \"Updated\" : \"Failed\") + \" from \" + current + \" to \" + (current + 10));\n                try {\n                    Thread.sleep(15);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        };\n        \n        executor.submit(task1);\n        \n        Thread mainThread = new Thread(task2);\n        mainThread.start();\n        \n        mainThread.join();\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final value: \" + cas.get());\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SimulatedCAS {\n    private int value;\n    \n    public SimulatedCAS(int initialValue) {\n        this.value = initialValue;\n    }\n    \n    public synchronized int get() {\n        return value;\n    }\n    \n    public synchronized int compareAndSwap(int expectedValue, int newValue) {\n        int oldValue = value;\n        if (oldValue == expectedValue) {\n            value = newValue;\n        }\n        return oldValue;\n    }\n    \n    public synchronized boolean compareAndSet(int expectedValue, int newValue) {\n        return compareAndSwap(expectedValue, newValue) == expectedValue;\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        SimulatedCAS cas = new SimulatedCAS(0);\n        ExecutorService executor = Executors.newFixedThreadPool(1);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                int current = cas.get();\n                while (!cas.compareAndSet(current, current + 1)) {\n                    current = cas.get();\n                }\n                System.out.println(\"Thread 1: Updated value to \" + (current + 1));\n            }\n        });\n        \n        for (int i = 0; i < 10; i++) {\n            int current = cas.get();\n            while (!cas.compareAndSet(current, current + 1)) {\n                current = cas.get();\n            }\n            System.out.println(\"Main thread: Updated value to \" + (current + 1));\n        }\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n        System.out.println(\"Final value: \" + cas.get());\n    }\n}"
        ],
        "graded_list": [
            false,
            true,
            false
        ],
        "ground_truth": "public class SimulatedCAS {\nprivate int value;\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized int compareAndSwap(int expectedValue, int newValue) {\nint oldValue = value;\nif (oldValue == expectedValue) {\nvalue = newValue;\n}\nreturn oldValue;\n}\n\npublic synchronized boolean compareAndSet(int expectedValue, int newValue) {\nreturn expectedValue == compareAndSwap(expectedValue, newValue);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal SimulatedCAS cas = new SimulatedCAS();\n\n// Reduce number of threads and iterations for faster JPF analysis\nint threadCount = 2;\nint iterationsPerThread = 3;\n\nThread[] threads = new Thread[threadCount];\nfor (int i = 0; i < threadCount; i++) {\nfinal int threadId = i;\nthreads[i] = new Thread(new Runnable() {\npublic void run() {\nfor (int j = 0; j < iterationsPerThread; j++) {\nint expected;\ndo {\nexpected = cas.get();\n} while (!cas.compareAndSet(expected, expected + 1));\nSystem.out.println(Thread.currentThread().getName() + \" incremented to: \" + cas.get());\n}\n}\n}, \"Worker-\" + threadId);\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final value: \" + cas.get());\nSystem.out.println(\"Expected value: \" + (threadCount * iterationsPerThread));\n}\n}",
        "max_depth": "101",
        "jpf_details": [
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 32.88%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 33.80%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 0.22%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=146389,visited=73202,backtracked=218844,end=71708\nsearch:             maxDepth=1010,constraints=514\nchoice generators:  thread=146043 (signal=0,lock=231,sharedRef=14258,threadApi=1019,reschedule=71772), data=0\nheap:               new=770849,released=3762708,maxLive=742,gcCycles=219164\ninstructions:       82528576\nmax memory:         1014MB\nloaded code:        classes=140,methods=2445\n\n====================================================== search finished",
            "at gov.nasa.jpf.search.DFSearch.search(DFSearch.java:79)\n\tat gov.nasa.jpf.JPF.run(JPF.java:613)\n\tat gov.nasa.jpf.JPF.start(JPF.java:189)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "jpf_result": [
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nSimulatedCAS.main()\n====================================================== search started: 11/17/25 3:37 PM\nMain thread: old value: 0, new value: 100\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)",
            "no errors detected",
            "JavaPathfinder core system v8.0 (rev 2345caaa002e15c6147d001d1ccd71e4b538f8e9) - (C) 2005-2014 United States Government. All rights reserved.\n====================================================== system under test\nSimulatedCAS.main()\n====================================================== search started: 11/17/25 3:38 PM\nMain thread: Updated value to 1\n...\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:498)\n\tat gov.nasa.jpf.tool.Run.call(Run.java:80)\n\tat gov.nasa.jpf.tool.RunJPF.main(RunJPF.java:116)"
        ],
        "codebleu_score": [
            62.77,
            60.44,
            61.16
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Thread confinement of local primitive and reference variables. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java program that models the process of loading animals onto an ark in pairs. The program should define classes and enums representing animals, their species and gender, and a mechanism for pairing animals based on species and gender compatibility. Each animal has a species and gender, and only animals of the same species and opposite genders can form a pair.\n\nThe main logic is implemented in a method called loadTheArk, which takes a collection of candidate animals as input and returns the number of valid pairs formed. Inside this method, animals are sorted using a custom comparator that orders them first by species and then by gender. This ensures that animals of the same species and opposite genders are grouped together for pairing.\n\nAdditionally, implement a class to represent the ark that can store these animal pairs, and a helper class to represent each pair of animals. Ensure proper encapsulation and thread confinement of variables within the method, preventing any unintended side effects or data sharing between threads. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. If the code includes any loops or iterations, please use the minimal iteration count. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class ArkLoader {\n    public static void main(String[] args) {\n        List<Animal> animals = Arrays.asList(\n            new Animal(Species.DOG, Gender.MALE),\n            new Animal(Species.DOG, Gender.FEMALE),\n            new Animal(Species.CAT, Gender.MALE),\n            new Animal(Species.CAT, Gender.FEMALE),\n            new Animal(Species.BIRD, Gender.MALE),\n            new Animal(Species.BIRD, Gender.FEMALE),\n            new Animal(Species.DOG, Gender.MALE),\n            new Animal(Species.CAT, Gender.FEMALE)\n        );\n        \n        Ark ark = new Ark();\n        int pairsLoaded = ark.loadTheArk(animals);\n        System.out.println(\"Number of pairs loaded: \" + pairsLoaded);\n        System.out.println(\"Pairs on the ark: \" + ark.getPairs());\n    }\n}\n\nenum Species {\n    DOG, CAT, BIRD, ELEPHANT, LION\n}\n\nenum Gender {\n    MALE, FEMALE\n}\n\nclass Animal {\n    private final Species species;\n    private final Gender gender;\n    \n    public Animal(Species species, Gender gender) {\n        this.species = species;\n        this.gender = gender;\n    }\n    \n    public Species getSpecies() {\n        return species;\n    }\n    \n    public Gender getGender() {\n        return gender;\n    }\n    \n    @Override\n    public String toString() {\n        return species + \" \" + gender;\n    }\n}\n\nclass AnimalPair {\n    private final Animal first;\n    private final Animal second;\n    \n    public AnimalPair(Animal first, Animal second) {\n        this.first = first;\n        this.second = second;\n    }\n    \n    public Animal getFirst() {\n        return first;\n    }\n    \n    public Animal getSecond() {\n        return second;\n    }\n    \n    @Override\n    public String toString() {\n        return \"(\" + first + \", \" + second + \")\";\n    }\n}\n\nclass Ark {\n    private final List<AnimalPair> pairs = Collections.synchronizedList(new ArrayList<>());\n    \n    public int loadTheArk(Collection<Animal> candidates) {\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        List<Animal> animalList = new ArrayList<>(candidates);\n        \n        Comparator<Animal> animalComparator = Comparator\n            .comparing(Animal::getSpecies)\n            .thenComparing(Animal::getGender);\n        \n        Future<List<Animal>> sortingTask = executor.submit(() -> {\n            List<Animal> sorted = new ArrayList<>(animalList);\n            Collections.sort(sorted, animalComparator);\n            return sorted;\n        });\n        \n        try {\n            List<Animal> sortedAnimals = sortingTask.get();\n            \n            int midPoint = sortedAnimals.size() / 2;\n            List<Animal> firstHalf = sortedAnimals.subList(0, midPoint);\n            List<Animal> secondHalf = sortedAnimals.subList(midPoint, sortedAnimals.size());\n            \n            Future<List<AnimalPair>> firstHalfPairing = executor.submit(() -> {\n                return pairAnimals(firstHalf);\n            });\n            \n            Future<List<AnimalPair>> secondHalfPairing = executor.submit(() -> {\n                return pairAnimals(secondHalf);\n            });\n            \n            List<AnimalPair> pairs1 = firstHalfPairing.get();\n            List<AnimalPair> pairs2 = secondHalfPairing.get();\n            \n            pairs.addAll(pairs1);\n            pairs.addAll(pairs2);\n            \n            if (midPoint > 0 && sortedAnimals.size() > midPoint) {\n                Animal lastOfFirst = sortedAnimals.get(midPoint - 1);\n                Animal firstOfSecond = sortedAnimals.get(midPoint);\n                if (canPair(lastOfFirst, firstOfSecond)) {\n                    pairs.add(new AnimalPair(lastOfFirst, firstOfSecond));\n                }\n            }\n            \n        } catch (InterruptedException | ExecutionException e) {\n            e.printStackTrace();\n        } finally {\n            executor.shutdown();\n        }\n        \n        return pairs.size();\n    }\n    \n    private List<AnimalPair> pairAnimals(List<Animal> animals) {\n        List<AnimalPair> localPairs = new ArrayList<>();\n        Map<Species, List<Animal>> speciesGroups = new HashMap<>();\n        \n        for (Animal animal : animals) {\n            speciesGroups.computeIfAbsent(animal.getSpecies(), k -> new ArrayList<>()).add(animal);\n        }\n        \n        for (Map.Entry<Species, List<Animal>> entry : speciesGroups.entrySet()) {\n            List<Animal> speciesAnimals = entry.getValue();\n            List<Animal> males = new ArrayList<>();\n            List<Animal> females = new ArrayList<>();\n            \n            for (Animal animal : speciesAnimals) {\n                if (animal.getGender() == Gender.MALE) {\n                    males.add(animal);\n                } else {\n                    females.add(animal);\n                }\n            }\n            \n            int pairCount = Math.min(males.size(), females.size());\n            for (int i = 0; i < pairCount; i++) {\n                localPairs.add(new AnimalPair(males.get(i), females.get(i)));\n            }\n        }\n        \n        return localPairs;\n    }\n    \n    private boolean canPair(Animal a1, Animal a2) {\n        return a1.getSpecies() == a2.getSpecies() && \n               a1.getGender() != a2.getGender();\n    }\n    \n    public List<AnimalPair> getPairs() {\n        return new ArrayList<>(pairs);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class ArkLoader {\n    public static void main(String[] args) throws Exception {\n        List<Animal> animals = Arrays.asList(\n            new Animal(Species.DOG, Gender.MALE),\n            new Animal(Species.DOG, Gender.FEMALE),\n            new Animal(Species.CAT, Gender.MALE),\n            new Animal(Species.CAT, Gender.FEMALE),\n            new Animal(Species.BIRD, Gender.MALE),\n            new Animal(Species.BIRD, Gender.FEMALE),\n            new Animal(Species.DOG, Gender.MALE),\n            new Animal(Species.CAT, Gender.FEMALE)\n        );\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        Future<Integer> future = executor.submit(() -> loadTheArk(animals));\n        \n        int pairs = future.get();\n        System.out.println(\"Number of pairs loaded: \" + pairs);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n    \n    public static int loadTheArk(Collection<Animal> candidates) {\n        List<Animal> sortedAnimals = new ArrayList<>(candidates);\n        Collections.sort(sortedAnimals, new AnimalComparator());\n        \n        Ark ark = new Ark();\n        int pairCount = 0;\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        List<Future<AnimalPair>> futures = new ArrayList<>();\n        \n        for (int i = 0; i < sortedAnimals.size() - 1; i++) {\n            final int index = i;\n            final List<Animal> localList = new ArrayList<>(sortedAnimals);\n            \n            Future<AnimalPair> future = executor.submit(() -> {\n                Animal first = localList.get(index);\n                Animal second = localList.get(index + 1);\n                \n                if (first.getSpecies() == second.getSpecies() && \n                    first.getGender() != second.getGender()) {\n                    return new AnimalPair(first, second);\n                }\n                return null;\n            });\n            \n            futures.add(future);\n        }\n        \n        for (Future<AnimalPair> future : futures) {\n            try {\n                AnimalPair pair = future.get();\n                if (pair != null) {\n                    synchronized (ark) {\n                        ark.addPair(pair);\n                        pairCount++;\n                    }\n                }\n            } catch (Exception e) {\n                e.printStackTrace();\n            }\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            e.printStackTrace();\n        }\n        \n        return pairCount;\n    }\n}\n\nenum Species {\n    DOG, CAT, BIRD, ELEPHANT, LION\n}\n\nenum Gender {\n    MALE, FEMALE\n}\n\nclass Animal {\n    private final Species species;\n    private final Gender gender;\n    \n    public Animal(Species species, Gender gender) {\n        this.species = species;\n        this.gender = gender;\n    }\n    \n    public Species getSpecies() {\n        return species;\n    }\n    \n    public Gender getGender() {\n        return gender;\n    }\n}\n\nclass AnimalComparator implements Comparator<Animal> {\n    @Override\n    public int compare(Animal a1, Animal a2) {\n        int speciesCompare = a1.getSpecies().compareTo(a2.getSpecies());\n        if (speciesCompare != 0) {\n            return speciesCompare;\n        }\n        return a1.getGender().compareTo(a2.getGender());\n    }\n}\n\nclass AnimalPair {\n    private final Animal first;\n    private final Animal second;\n    \n    public AnimalPair(Animal first, Animal second) {\n        this.first = first;\n        this.second = second;\n    }\n    \n    public Animal getFirst() {\n        return first;\n    }\n    \n    public Animal getSecond() {\n        return second;\n    }\n}\n\nclass Ark {\n    private final List<AnimalPair> pairs;\n    \n    public Ark() {\n        this.pairs = new ArrayList<>();\n    }\n    \n    public void addPair(AnimalPair pair) {\n        pairs.add(pair);\n    }\n    \n    public List<AnimalPair> getPairs() {\n        return new ArrayList<>(pairs);\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.stream.*;\n\npublic class ArkLoader {\n    public static void main(String[] args) throws InterruptedException, ExecutionException {\n        List<Animal> animals = Arrays.asList(\n            new Animal(Species.DOG, Gender.MALE),\n            new Animal(Species.DOG, Gender.FEMALE),\n            new Animal(Species.CAT, Gender.MALE),\n            new Animal(Species.CAT, Gender.FEMALE),\n            new Animal(Species.DOG, Gender.MALE),\n            new Animal(Species.CAT, Gender.FEMALE),\n            new Animal(Species.ELEPHANT, Gender.MALE),\n            new Animal(Species.ELEPHANT, Gender.FEMALE),\n            new Animal(Species.LION, Gender.MALE),\n            new Animal(Species.LION, Gender.FEMALE)\n        );\n        \n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        Future<Integer> future1 = executor.submit(() -> {\n            List<Animal> subset1 = animals.subList(0, animals.size() / 2);\n            return loadTheArk(subset1);\n        });\n        \n        Future<Integer> future2 = executor.submit(() -> {\n            List<Animal> subset2 = animals.subList(animals.size() / 2, animals.size());\n            return loadTheArk(subset2);\n        });\n        \n        int pairs1 = future1.get();\n        int pairs2 = future2.get();\n        \n        System.out.println(\"Total pairs loaded: \" + (pairs1 + pairs2));\n        \n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n    }\n    \n    public static int loadTheArk(Collection<Animal> candidates) {\n        List<Animal> sortedAnimals = new ArrayList<>(candidates);\n        sortedAnimals.sort(new AnimalComparator());\n        \n        Ark ark = new Ark();\n        int pairCount = 0;\n        \n        for (int i = 0; i < sortedAnimals.size() - 1; i++) {\n            Animal first = sortedAnimals.get(i);\n            Animal second = sortedAnimals.get(i + 1);\n            \n            if (first.getSpecies() == second.getSpecies() && \n                first.getGender() != second.getGender()) {\n                AnimalPair pair = new AnimalPair(first, second);\n                ark.addPair(pair);\n                pairCount++;\n                i++;\n            }\n        }\n        \n        return pairCount;\n    }\n}\n\nenum Species {\n    DOG, CAT, ELEPHANT, LION, TIGER, BEAR, RABBIT, HORSE\n}\n\nenum Gender {\n    MALE, FEMALE\n}\n\nclass Animal {\n    private final Species species;\n    private final Gender gender;\n    \n    public Animal(Species species, Gender gender) {\n        this.species = species;\n        this.gender = gender;\n    }\n    \n    public Species getSpecies() {\n        return species;\n    }\n    \n    public Gender getGender() {\n        return gender;\n    }\n}\n\nclass AnimalComparator implements Comparator<Animal> {\n    @Override\n    public int compare(Animal a1, Animal a2) {\n        int speciesCompare = a1.getSpecies().compareTo(a2.getSpecies());\n        if (speciesCompare != 0) {\n            return speciesCompare;\n        }\n        return a1.getGender().compareTo(a2.getGender());\n    }\n}\n\nclass AnimalPair {\n    private final Animal first;\n    private final Animal second;\n    \n    public AnimalPair(Animal first, Animal second) {\n        this.first = first;\n        this.second = second;\n    }\n    \n    public Animal getFirst() {\n        return first;\n    }\n    \n    public Animal getSecond() {\n        return second;\n    }\n}\n\nclass Ark {\n    private final List<AnimalPair> pairs;\n    \n    public Ark() {\n        this.pairs = Collections.synchronizedList(new ArrayList<>());\n    }\n    \n    public void addPair(AnimalPair pair) {\n        pairs.add(pair);\n    }\n    \n    public List<AnimalPair> getPairs() {\n        return new ArrayList<>(pairs);\n    }\n}"
        ],
        "graded_list": [
            false,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class Animals {\nprivate final Ark ark;\n\npublic Animals() {\nthis.ark = new Ark();\n}\n\npublic int loadTheArk(Collection<Animal> candidates) {\nSortedSet<Animal> animals;\nint numPairs = 0;\nAnimal candidate = null;\n\nanimals = new TreeSet<>(new SpeciesGenderComparator());\nanimals.addAll(candidates);\nfor (Animal a : animals) {\nif (candidate == null || !candidate.isPotentialMate(a)) {\ncandidate = a;\n} else {\nark.load(new AnimalPair(candidate, a));\n++numPairs;\ncandidate = null;\n}\n}\nreturn numPairs;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nAnimals animalsApp = new Animals();\n\nCollection<Animal> group1 = createSampleAnimals(4);\nCollection<Animal> group2 = createSampleAnimals(4);\n\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nexecutor.submit(() -> {\nint pairs = animalsApp.loadTheArk(group1);\nSystem.out.println(Thread.currentThread().getName() + \" loaded \" + pairs + \" pairs.\");\n});\n\nexecutor.submit(() -> {\nint pairs = animalsApp.loadTheArk(group2);\nSystem.out.println(Thread.currentThread().getName() + \" loaded \" + pairs + \" pairs.\");\n});\n\nexecutor.shutdown();\n}\n\nprivate static Collection<Animal> createSampleAnimals(int count) {\nList<Animal> list = new ArrayList<>();\nRandom rand = new Random();\nSpecies[] speciesArray = Species.values();\nGender[] genders = Gender.values();\n\nfor (int i = 0; i < count; i++) {\nAnimal animal = new Animal();\nanimal.species = speciesArray[rand.nextInt(speciesArray.length)];\nanimal.gender = genders[rand.nextInt(genders.length)];\nlist.add(animal);\n}\n\nreturn list;\n}\n\nstatic class Animal {\nSpecies species;\nGender gender;\n\npublic boolean isPotentialMate(Animal other) {\nreturn species == other.species && gender != other.gender;\n}\n}\n\nenum Species {\nAARDVARK, BENGAL_TIGER, CARIBOU, DINGO\n}\n\nenum Gender {\nMALE, FEMALE\n}\n\nstatic class AnimalPair {\nprivate final Animal one, two;\n\npublic AnimalPair(Animal one, Animal two) {\nthis.one = one;\nthis.two = two;\n}\n}\n\nstatic class SpeciesGenderComparator implements Comparator<Animal> {\npublic int compare(Animal one, Animal two) {\nint speciesCompare = one.species.compareTo(two.species);\nreturn (speciesCompare != 0)\n? speciesCompare\n: one.gender.compareTo(two.gender);\n}\n}\n\nstatic class Ark {\nprivate final Set<AnimalPair> loadedAnimals = Collections.synchronizedSet(new HashSet<>());\n\npublic void load(AnimalPair pair) {\nloadedAnimals.add(pair);\nSystem.out.println(Thread.currentThread().getName() + \" loaded a pair: \" + pair.hashCode());\n}\n}\n}",
        "max_depth": "133",
        "jpf_details": [
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=760,released=0,maxLive=0,gcCycles=0\ninstructions:       7710\nmax memory:         981MB\nloaded code:        classes=137,methods=2640\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 34.52%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.52%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 14.66%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 37.87%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=79073,visited=57595,backtracked=135348,end=3328\nsearch:             maxDepth=1330,constraints=16141\nchoice generators:  thread=70085 (signal=0,lock=7,sharedRef=34428,threadApi=3,reschedule=31275), data=0\nheap:               new=3970172,released=1417773,maxLive=1115,gcCycles=136661\ninstructions:       44071090\nmax memory:         1015MB\nloaded code:        classes=155,methods=2742\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 42.96%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 29.91%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 37.62%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=90691,visited=74486,backtracked=163927,end=27496\nsearch:             maxDepth=1330,constraints=3090\nchoice generators:  thread=88767 (signal=0,lock=10,sharedRef=38526,threadApi=2,reschedule=45710), data=0\nheap:               new=568642,released=1907157,maxLive=1113,gcCycles=165175\ninstructions:       70648780\nmax memory:         1009MB\nloaded code:        classes=162,methods=2812\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.ClassCastException: java.util.Comparator...\"",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            55.7,
            53.34,
            52.95
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Thread-safe lazy initialization. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a thread-safe lazy initialization implementation in Java. The class should ensure that a resource is only instantiated when it is first requested, and the initialization must be synchronized to prevent race conditions in a multi-threaded environment. Use a static method to provide access to the shared instance of the resource. Do not use double-checked locking; instead, rely on coarse-grained synchronization to keep the implementation simple and safe. Also, define a placeholder nested Resource class that represents the lazily initialized resource. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class LazyInitialization {\n    \n    private static Resource instance;\n    \n    public static synchronized Resource getInstance() {\n        if (instance == null) {\n            instance = new Resource();\n        }\n        return instance;\n    }\n    \n    static class Resource {\n        private final long creationTime;\n        private final long threadId;\n        \n        public Resource() {\n            this.creationTime = System.currentTimeMillis();\n            this.threadId = Thread.currentThread().getId();\n            System.out.println(\"Resource created by thread \" + threadId + \" at \" + creationTime);\n        }\n        \n        public void doWork() {\n            System.out.println(\"Working with resource created by thread \" + threadId + \n                             \" (called from thread \" + Thread.currentThread().getId() + \")\");\n        }\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 10; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                System.out.println(\"Task \" + taskId + \" requesting resource from thread \" + \n                                 Thread.currentThread().getId());\n                Resource resource = getInstance();\n                resource.doWork();\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class LazyInitialization {\n    \n    private static Resource instance;\n    \n    public static synchronized Resource getInstance() {\n        if (instance == null) {\n            instance = new Resource();\n        }\n        return instance;\n    }\n    \n    static class Resource {\n        private final long creationTime;\n        private final long threadId;\n        \n        public Resource() {\n            this.creationTime = System.currentTimeMillis();\n            this.threadId = Thread.currentThread().getId();\n            System.out.println(\"Resource created by thread \" + threadId + \" at \" + creationTime);\n        }\n        \n        public void doWork() {\n            System.out.println(\"Resource working in thread \" + Thread.currentThread().getId());\n        }\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 10; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                System.out.println(\"Task \" + taskId + \" requesting resource from thread \" + Thread.currentThread().getId());\n                Resource resource = LazyInitialization.getInstance();\n                resource.doWork();\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class LazyInitialization {\n    \n    private static Resource instance;\n    \n    public static synchronized Resource getInstance() {\n        if (instance == null) {\n            instance = new Resource();\n        }\n        return instance;\n    }\n    \n    static class Resource {\n        private final long creationTime;\n        private final long threadId;\n        \n        public Resource() {\n            this.creationTime = System.currentTimeMillis();\n            this.threadId = Thread.currentThread().getId();\n            System.out.println(\"Resource created by thread: \" + threadId + \" at \" + creationTime);\n        }\n        \n        public void doWork() {\n            System.out.println(\"Working with resource created by thread \" + threadId + \n                             \", accessed by thread \" + Thread.currentThread().getId());\n        }\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        \n        for (int i = 0; i < 10; i++) {\n            final int taskId = i;\n            executor.submit(() -> {\n                System.out.println(\"Task \" + taskId + \" requesting resource from thread \" + \n                                 Thread.currentThread().getId());\n                Resource resource = LazyInitialization.getInstance();\n                resource.doWork();\n            });\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\n\npublic class SafeLazyInitialization {\nprivate static Resource instance;\n\nprivate SafeLazyInitialization() {}\n\npublic static synchronized Resource getInstance() {\nif (instance == null) {\ninstance = new Resource();\n}\nreturn instance;\n}\n\nstatic class Resource {\nprivate Resource() {}\n\npublic void doSomething() {}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nExecutorService executor = Executors.newFixedThreadPool(2);\n\nfor (int i = 0; i < 2; i++) {\nexecutor.submit(() -> {\nResource r = SafeLazyInitialization.getInstance();\nr.doSomething();\n});\n}\n\nexecutor.shutdown();\nwhile (!executor.isTerminated()) {\nThread.sleep(10);\n}\n}\n}",
        "max_depth": "88",
        "jpf_details": [
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 71.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 71.35%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 71.34%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=149087,visited=130125,backtracked=278332,end=0\nsearch:             maxDepth=880,constraints=120389\nchoice generators:  thread=77562 (signal=0,lock=4014,sharedRef=61688,threadApi=3,reschedule=4344), data=0\nheap:               new=246460,released=347858,maxLive=770,gcCycles=259668\ninstructions:       17676843\nmax memory:         1019MB\nloaded code:        classes=135,methods=2392\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 71.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 71.36%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 71.34%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=149996,visited=130577,backtracked=279694,end=0\nsearch:             maxDepth=880,constraints=121114\nchoice generators:  thread=77929 (signal=0,lock=4033,sharedRef=61957,threadApi=3,reschedule=4354), data=0\nheap:               new=207235,released=340932,maxLive=766,gcCycles=260972\ninstructions:       17654212\nmax memory:         1019MB\nloaded code:        classes=135,methods=2392\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 71.46%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 71.37%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 71.36%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=149974,visited=130125,backtracked=279219,end=0\nsearch:             maxDepth=880,constraints=121190\nchoice generators:  thread=77752 (signal=0,lock=4007,sharedRef=61769,threadApi=3,reschedule=4341), data=0\nheap:               new=229671,released=346642,maxLive=768,gcCycles=260605\ninstructions:       17677177\nmax memory:         1019MB\nloaded code:        classes=135,methods=2392\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            74.15,
            71.64,
            71.64
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Thread-safe mutable integer holder. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a thread-safe class in Java that holds a mutable integer value. The class should have methods to get and set the value, both of which must be synchronized to ensure safe access and modification from multiple threads. Use internal locking (synchronized methods) to protect the integrity of the shared state. Additionally, include appropriate annotations to indicate thread-safety and specify that the internal state is guarded by the object's intrinsic lock. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "public class ThreadSafeCounter {\n    private int value;\n\n    public ThreadSafeCounter(int initialValue) {\n        this.value = initialValue;\n    }\n\n    public synchronized int getValue() {\n        return value;\n    }\n\n    public synchronized void setValue(int newValue) {\n        this.value = newValue;\n    }\n\n    public synchronized void increment() {\n        value++;\n    }\n\n    public synchronized void decrement() {\n        value--;\n    }\n\n    public static void main(String[] args) {\n        ThreadSafeCounter counter = new ThreadSafeCounter(0);\n\n        Thread incrementThread = new Thread(() -> {\n            for (int i = 0; i < 1000; i++) {\n                counter.increment();\n                if (i % 100 == 0) {\n                    System.out.println(\"Increment thread: \" + counter.getValue());\n                }\n            }\n        });\n\n        Thread decrementThread = new Thread(() -> {\n            for (int i = 0; i < 500; i++) {\n                counter.decrement();\n                if (i % 100 == 0) {\n                    System.out.println(\"Decrement thread: \" + counter.getValue());\n                }\n            }\n        });\n\n        incrementThread.start();\n        decrementThread.start();\n\n        try {\n            incrementThread.join();\n            decrementThread.join();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n\n        System.out.println(\"Final value: \" + counter.getValue());\n    }\n}",
            "public class ThreadSafeInteger {\n    private int value;\n    \n    public ThreadSafeInteger(int initialValue) {\n        this.value = initialValue;\n    }\n    \n    public synchronized int getValue() {\n        return value;\n    }\n    \n    public synchronized void setValue(int newValue) {\n        this.value = newValue;\n    }\n    \n    public static void main(String[] args) {\n        ThreadSafeInteger sharedInteger = new ThreadSafeInteger(0);\n        \n        Thread incrementThread = new Thread(() -> {\n            for (int i = 0; i < 1000; i++) {\n                int currentValue = sharedInteger.getValue();\n                sharedInteger.setValue(currentValue + 1);\n                try {\n                    Thread.sleep(1);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        Thread decrementThread = new Thread(() -> {\n            for (int i = 0; i < 500; i++) {\n                int currentValue = sharedInteger.getValue();\n                sharedInteger.setValue(currentValue - 1);\n                try {\n                    Thread.sleep(2);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        incrementThread.start();\n        decrementThread.start();\n        \n        try {\n            incrementThread.join();\n            decrementThread.join();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final value: \" + sharedInteger.getValue());\n    }\n}",
            "public class ThreadSafeInteger {\n    private int value;\n    \n    public ThreadSafeInteger(int initialValue) {\n        this.value = initialValue;\n    }\n    \n    public synchronized int getValue() {\n        return value;\n    }\n    \n    public synchronized void setValue(int newValue) {\n        this.value = newValue;\n    }\n    \n    public static void main(String[] args) {\n        ThreadSafeInteger sharedInteger = new ThreadSafeInteger(0);\n        \n        Thread incrementThread = new Thread(() -> {\n            for (int i = 0; i < 1000; i++) {\n                int current = sharedInteger.getValue();\n                sharedInteger.setValue(current + 1);\n                try {\n                    Thread.sleep(1);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n            System.out.println(\"Increment thread finished. Final value: \" + sharedInteger.getValue());\n        });\n        \n        Thread decrementThread = new Thread(() -> {\n            for (int i = 0; i < 500; i++) {\n                int current = sharedInteger.getValue();\n                sharedInteger.setValue(current - 1);\n                try {\n                    Thread.sleep(2);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n            System.out.println(\"Decrement thread finished. Final value: \" + sharedInteger.getValue());\n        });\n        \n        incrementThread.start();\n        decrementThread.start();\n        \n        try {\n            incrementThread.join();\n            decrementThread.join();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Main thread finished. Final value: \" + sharedInteger.getValue());\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "/**\n* A thread-safe integer wrapper using synchronized methods.\n*/\npublic class LLMC {\nprivate int value;\n\npublic LLMC(int initialValue) {\nthis.value = initialValue;\n}\n\npublic LLMC() {\nthis(0);\n}\n\npublic synchronized int get() {\nreturn value;\n}\n\npublic synchronized void set(int value) {\nthis.value = value;\n}\n\npublic synchronized int increment() {\nreturn ++value;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC counter = new LLMC();\n\nfinal int NUM_THREADS = 2;\nfinal int INCREMENTS_PER_THREAD = 2;\n\nThread[] threads = new Thread[NUM_THREADS];\n\nfor (int i = 0; i < NUM_THREADS; i++) {\nthreads[i] = new Thread(() -> {\nfor (int j = 0; j < INCREMENTS_PER_THREAD; j++) {\ncounter.increment();\n}\n});\nthreads[i].start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"Final counter value: \" + counter.get());\nSystem.out.println(\"Expected value: \" + (NUM_THREADS * INCREMENTS_PER_THREAD));\n}\n}",
        "max_depth": "20",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.08%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 53.62%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 53.71%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=103699,visited=120804,backtracked=224503,end=0\nsearch:             maxDepth=200,constraints=3485\nchoice generators:  thread=101797 (signal=0,lock=49664,sharedRef=41837,threadApi=3,reschedule=10293), data=0\nheap:               new=58830,released=103883,maxLive=479,gcCycles=182791\ninstructions:       1826203\nmax memory:         1013MB\nloaded code:        classes=83,methods=1822\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.99%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.98%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=410531,visited=303607,backtracked=713940,end=0\nsearch:             maxDepth=200,constraints=49488\nchoice generators:  thread=380658 (signal=0,lock=175579,sharedRef=96266,threadApi=70650,reschedule=38163), data=0\nheap:               new=481,released=10,maxLive=471,gcCycles=466520\ninstructions:       4592126\nmax memory:         1022MB\nloaded code:        classes=83,methods=1820\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.99%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 49.98%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=410022,visited=303207,backtracked=713031,end=0\nsearch:             maxDepth=200,constraints=49454\nchoice generators:  thread=380168 (signal=0,lock=175350,sharedRef=96144,threadApi=70560,reschedule=38114), data=0\nheap:               new=481,released=10,maxLive=471,gcCycles=465905\ninstructions:       4586380\nmax memory:         1022MB\nloaded code:        classes=83,methods=1820\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            55.95,
            57.77,
            61.4
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using CountDownLatch for starting and stopping threads in timing tests. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: The Java 8 multi-threading performance testing tool utilizes CountDownLatch for thread synchronization and execution timing. The core method timeTasks accepts the number of threads and a task logic, employing two CountDownLatch instances (a \"start gate\" for synchronized thread initiation and an \"end gate\" for completion waiting) to ensure all threads begin simultaneously and the main thread waits for their completion. High-precision timing is achieved with System.nanoTime(), while manual thread creation and Lambda expressions implement the task logic. The design handles thread interruption by preserving the interrupt status and supports functional extension through arbitrary Runnable task inputs. This structure enables accurate measurement of parallel execution performance in scenarios like simulated workload testing. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.CountDownLatch;\n\npublic class ConcurrentPerformanceTester {\n    \n    public static void main(String[] args) {\n        ConcurrentPerformanceTester tester = new ConcurrentPerformanceTester();\n        \n        Runnable task = () -> {\n            long sum = 0;\n            for (int i = 0; i < 1000000; i++) {\n                sum += i;\n            }\n        };\n        \n        try {\n            long time1 = tester.timeTasks(1, task);\n            System.out.println(\"Single thread execution time: \" + time1 + \" ns\");\n            \n            long time2 = tester.timeTasks(2, task);\n            System.out.println(\"Two threads execution time: \" + time2 + \" ns\");\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            System.err.println(\"Test interrupted\");\n        }\n    }\n    \n    public long timeTasks(int nThreads, Runnable task) throws InterruptedException {\n        if (nThreads > 2) {\n            nThreads = 2;\n        }\n        \n        CountDownLatch startGate = new CountDownLatch(1);\n        CountDownLatch endGate = new CountDownLatch(nThreads);\n        \n        for (int i = 0; i < nThreads; i++) {\n            Thread t = new Thread(() -> {\n                try {\n                    startGate.await();\n                    try {\n                        task.run();\n                    } finally {\n                        endGate.countDown();\n                    }\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            });\n            t.start();\n        }\n        \n        long startTime = System.nanoTime();\n        startGate.countDown();\n        endGate.await();\n        long endTime = System.nanoTime();\n        \n        return endTime - startTime;\n    }\n}",
            "import java.util.concurrent.CountDownLatch;\n\npublic class ConcurrentPerformanceTester {\n    \n    public static void main(String[] args) {\n        ConcurrentPerformanceTester tester = new ConcurrentPerformanceTester();\n        \n        Runnable task = () -> {\n            double result = 0;\n            for (int i = 0; i < 1000000; i++) {\n                result += Math.sqrt(i);\n            }\n        };\n        \n        try {\n            long executionTime = tester.timeTasks(1, task);\n            System.out.println(\"Execution time: \" + executionTime + \" nanoseconds\");\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            System.err.println(\"Test interrupted\");\n        }\n    }\n    \n    public long timeTasks(int nThreads, Runnable task) throws InterruptedException {\n        final CountDownLatch startGate = new CountDownLatch(1);\n        final CountDownLatch endGate = new CountDownLatch(nThreads);\n        \n        for (int i = 0; i < nThreads; i++) {\n            Thread t = new Thread(() -> {\n                try {\n                    startGate.await();\n                    try {\n                        task.run();\n                    } finally {\n                        endGate.countDown();\n                    }\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            });\n            t.start();\n        }\n        \n        long startTime = System.nanoTime();\n        startGate.countDown();\n        endGate.await();\n        long endTime = System.nanoTime();\n        \n        return endTime - startTime;\n    }\n}",
            "import java.util.concurrent.CountDownLatch;\n\npublic class ConcurrentPerformanceTester {\n    \n    public static void main(String[] args) {\n        ConcurrentPerformanceTester tester = new ConcurrentPerformanceTester();\n        \n        Runnable task = () -> {\n            long sum = 0;\n            for (int i = 0; i < 1000000; i++) {\n                sum += i;\n            }\n        };\n        \n        try {\n            long time1 = tester.timeTasks(1, task);\n            System.out.println(\"Single thread execution time: \" + time1 + \" ns\");\n            \n            long time2 = tester.timeTasks(2, task);\n            System.out.println(\"Two threads execution time: \" + time2 + \" ns\");\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            System.err.println(\"Test interrupted\");\n        }\n    }\n    \n    public long timeTasks(int nThreads, Runnable task) throws InterruptedException {\n        if (nThreads > 2) {\n            nThreads = 2;\n        }\n        \n        CountDownLatch startGate = new CountDownLatch(1);\n        CountDownLatch endGate = new CountDownLatch(nThreads);\n        \n        for (int i = 0; i < nThreads; i++) {\n            Thread t = new Thread(() -> {\n                try {\n                    startGate.await();\n                    try {\n                        task.run();\n                    } finally {\n                        endGate.countDown();\n                    }\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            });\n            t.start();\n        }\n        \n        long startTime = System.nanoTime();\n        startGate.countDown();\n        endGate.await();\n        long endTime = System.nanoTime();\n        \n        return endTime - startTime;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.*;\n\n/**\n* TestHarness\n*\n* Using CountDownLatch to control the start and stop of threads in timing tests.\n*\n* @author Brian Goetz and Tim Peierls\n*/\npublic class TestHarness {\npublic long timeTasks(int nThreads, final Runnable task) throws InterruptedException {\nfinal CountDownLatch startGate = new CountDownLatch(1);\nfinal CountDownLatch endGate = new CountDownLatch(nThreads);\n\nfor (int i = 0; i < nThreads; i++) {\nThread t = new Thread(() -> {\ntry {\nstartGate.await();\ntry {\ntask.run();\n} finally {\nendGate.countDown();\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n});\nt.start();\n}\n\nlong start = System.nanoTime();\nstartGate.countDown(); // Allow all threads to start running\nendGate.await(); // Wait for all threads to finish\nlong end = System.nanoTime();\nreturn end - start;\n}\n\npublic static void main(String[] args) throws InterruptedException {\nTestHarness harness = new TestHarness();\n\n// Define a simple task: sleep for a while\nRunnable task = () -> {\ntry {\nSystem.out.println(Thread.currentThread().getName() + \" is running.\");\nThread.sleep(1000); // Simulate a time-consuming operation\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n};\n\nint nThreads = 2; // Run with 2 threads\nlong duration = harness.timeTasks(nThreads, task);\n\nSystem.out.printf(\"All %d tasks completed in %.3f seconds.%n\",\nnThreads, duration / 1_00.0);\n}\n}",
        "max_depth": "22",
        "jpf_details": [
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 31.71%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 0.27%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 42.85%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 42.47%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=8523,visited=1096,backtracked=9400,end=0\nsearch:             maxDepth=220,constraints=1570\nchoice generators:  thread=6995 (signal=0,lock=91,sharedRef=1501,threadApi=23,reschedule=4905), data=0\nheap:               new=6589,released=2076,maxLive=531,gcCycles=4376\ninstructions:       311730425\nmax memory:         981MB\nloaded code:        classes=92,methods=1953\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 54.42%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 0.71%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=4743,visited=13,backtracked=4756,end=0\nsearch:             maxDepth=220,constraints=22\nchoice generators:  thread=4722 (signal=0,lock=15,sharedRef=15,threadApi=1,reschedule=4672), data=0\nheap:               new=797,released=82,maxLive=521,gcCycles=85\ninstructions:       234868703\nmax memory:         981MB\nloaded code:        classes=92,methods=1953\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 31.37%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 0.27%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 42.91%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 42.77%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=8684,visited=1115,backtracked=9579,end=0\nsearch:             maxDepth=220,constraints=1628\nchoice generators:  thread=7099 (signal=0,lock=91,sharedRef=1551,threadApi=23,reschedule=4943), data=0\nheap:               new=6633,released=2083,maxLive=531,gcCycles=4507\ninstructions:       316087576\nmax memory:         981MB\nloaded code:        classes=92,methods=1953\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            62.35,
            59.98,
            62.35
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using FutureTask to preload data that is needed later. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java class called Preloader that simulates the preloading of data using a separate thread. The class should use a FutureTask to perform the data loading asynchronously and provide two main operations: a method to start the background task and another to retrieve the result of the task when needed.\n\nThe class should include:\n\nA method ProductInfo loadProductInfo() which simulates loading data and may throw a custom exception called DataLoadException.\nA FutureTask that wraps a Callable to execute the loadProductInfo method in the background.\nA dedicated Thread instance to run the FutureTask.\nA start() method to begin the execution of the background task.\nA get() method that returns the loaded ProductInfo and propagates any exceptions thrown during the loading process, including properly handling and rethrowing them (e.g., wrapping unexpected exceptions using a utility-like approach).\nAlso define:\n\nAn interface ProductInfo as a placeholder for the loaded data type.\nA custom exception class DataLoadException that extends Exception.\nEnsure the code is structured to be non-blocking during data loading but blocks only when retrieving the result via get(), and correctly handles error propagation from the background task. Write a Java class called Preloader that simulates the preloading of data using a separate thread. The class should use a FutureTask to perform the data loading asynchronously and provide two main operations: a method to start the background task and another to retrieve the result of the task when needed.\n\nThe class should include:\n\nA method ProductInfo loadProductInfo() which simulates loading data and may throw a custom exception called DataLoadException.\nA FutureTask that wraps a Callable to execute the loadProductInfo method in the background.\nA dedicated Thread instance to run the FutureTask.\nA start() method to begin the execution of the background task.\nA get() method that returns the loaded ProductInfo and propagates any exceptions thrown during the loading process, including properly handling and rethrowing them (e.g., wrapping unexpected exceptions using a utility-like approach).\nAlso define:\n\nAn interface ProductInfo as a placeholder for the loaded data type.\nA custom exception class DataLoadException that extends Exception.\nEnsure the code is structured to be non-blocking during data loading but blocks only when retrieving the result via get(), and correctly handles error propagation from the background task. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.TimeUnit;\n\ninterface ProductInfo {\n    String getName();\n    double getPrice();\n}\n\nclass DataLoadException extends Exception {\n    public DataLoadException(String message) {\n        super(message);\n    }\n    \n    public DataLoadException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ProductInfoImpl implements ProductInfo {\n    private final String name;\n    private final double price;\n    \n    public ProductInfoImpl(String name, double price) {\n        this.name = name;\n        this.price = price;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public double getPrice() {\n        return price;\n    }\n}\n\nclass Preloader {\n    private final FutureTask<ProductInfo> future;\n    private final Thread thread;\n    \n    public Preloader() {\n        this.future = new FutureTask<>(new Callable<ProductInfo>() {\n            @Override\n            public ProductInfo call() throws DataLoadException {\n                return loadProductInfo();\n            }\n        });\n        this.thread = new Thread(future);\n    }\n    \n    private ProductInfo loadProductInfo() throws DataLoadException {\n        try {\n            TimeUnit.SECONDS.sleep(2);\n            if (Math.random() > 0.7) {\n                throw new DataLoadException(\"Failed to load product data\");\n            }\n            return new ProductInfoImpl(\"Sample Product\", 99.99);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new DataLoadException(\"Loading interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        thread.start();\n    }\n    \n    public ProductInfo get() throws DataLoadException {\n        try {\n            return future.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof DataLoadException) {\n                throw (DataLoadException) cause;\n            } else {\n                throw launderThrowable(cause);\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new DataLoadException(\"Interrupted while waiting for result\", e);\n        }\n    }\n    \n    private static RuntimeException launderThrowable(Throwable t) {\n        if (t instanceof RuntimeException) {\n            return (RuntimeException) t;\n        } else if (t instanceof Error) {\n            throw (Error) t;\n        } else {\n            throw new IllegalStateException(\"Unexpected exception\", t);\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Preloader preloader = new Preloader();\n        System.out.println(\"Starting preloader...\");\n        preloader.start();\n        \n        System.out.println(\"Doing other work...\");\n        try {\n            TimeUnit.SECONDS.sleep(1);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Retrieving preloaded data...\");\n        try {\n            ProductInfo product = preloader.get();\n            System.out.println(\"Product loaded: \" + product.getName() + \" - $\" + product.getPrice());\n        } catch (DataLoadException e) {\n            System.err.println(\"Failed to load product: \" + e.getMessage());\n        }\n    }\n}",
            "import java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.TimeUnit;\n\ninterface ProductInfo {\n    String getName();\n    double getPrice();\n}\n\nclass DataLoadException extends Exception {\n    public DataLoadException(String message) {\n        super(message);\n    }\n    \n    public DataLoadException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ProductInfoImpl implements ProductInfo {\n    private final String name;\n    private final double price;\n    \n    public ProductInfoImpl(String name, double price) {\n        this.name = name;\n        this.price = price;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public double getPrice() {\n        return price;\n    }\n}\n\nclass Preloader {\n    private final FutureTask<ProductInfo> future;\n    private final Thread thread;\n    \n    public Preloader() {\n        this.future = new FutureTask<>(new Callable<ProductInfo>() {\n            @Override\n            public ProductInfo call() throws DataLoadException {\n                return loadProductInfo();\n            }\n        });\n        this.thread = new Thread(future);\n    }\n    \n    private ProductInfo loadProductInfo() throws DataLoadException {\n        try {\n            TimeUnit.SECONDS.sleep(2);\n            if (Math.random() > 0.7) {\n                throw new DataLoadException(\"Failed to load product information\");\n            }\n            return new ProductInfoImpl(\"Sample Product\", 99.99);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new DataLoadException(\"Loading was interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        thread.start();\n    }\n    \n    public ProductInfo get() throws DataLoadException, InterruptedException {\n        try {\n            return future.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof DataLoadException) {\n                throw (DataLoadException) cause;\n            } else if (cause instanceof RuntimeException) {\n                throw (RuntimeException) cause;\n            } else if (cause instanceof Error) {\n                throw (Error) cause;\n            } else {\n                throw new DataLoadException(\"Unexpected exception during loading\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Preloader preloader = new Preloader();\n        \n        System.out.println(\"Starting preloader...\");\n        preloader.start();\n        \n        System.out.println(\"Doing other work while data loads...\");\n        try {\n            TimeUnit.SECONDS.sleep(1);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Now retrieving loaded data...\");\n        try {\n            ProductInfo info = preloader.get();\n            System.out.println(\"Product loaded: \" + info.getName() + \" - $\" + info.getPrice());\n        } catch (DataLoadException e) {\n            System.err.println(\"Failed to load data: \" + e.getMessage());\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            System.err.println(\"Thread was interrupted\");\n        }\n    }\n}",
            "import java.util.concurrent.Callable;\nimport java.util.concurrent.ExecutionException;\nimport java.util.concurrent.FutureTask;\nimport java.util.concurrent.TimeUnit;\n\ninterface ProductInfo {\n    String getName();\n    double getPrice();\n}\n\nclass DataLoadException extends Exception {\n    public DataLoadException(String message) {\n        super(message);\n    }\n    \n    public DataLoadException(String message, Throwable cause) {\n        super(message, cause);\n    }\n}\n\nclass ProductInfoImpl implements ProductInfo {\n    private final String name;\n    private final double price;\n    \n    public ProductInfoImpl(String name, double price) {\n        this.name = name;\n        this.price = price;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public double getPrice() {\n        return price;\n    }\n}\n\nclass Preloader {\n    private final FutureTask<ProductInfo> future;\n    private final Thread thread;\n    \n    public Preloader() {\n        this.future = new FutureTask<>(new Callable<ProductInfo>() {\n            @Override\n            public ProductInfo call() throws DataLoadException {\n                return loadProductInfo();\n            }\n        });\n        this.thread = new Thread(future);\n    }\n    \n    private ProductInfo loadProductInfo() throws DataLoadException {\n        try {\n            TimeUnit.SECONDS.sleep(2);\n            if (Math.random() > 0.7) {\n                throw new DataLoadException(\"Failed to load product data\");\n            }\n            return new ProductInfoImpl(\"Sample Product\", 99.99);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new DataLoadException(\"Loading interrupted\", e);\n        }\n    }\n    \n    public void start() {\n        thread.start();\n    }\n    \n    public ProductInfo get() throws DataLoadException, InterruptedException {\n        try {\n            return future.get();\n        } catch (ExecutionException e) {\n            Throwable cause = e.getCause();\n            if (cause instanceof DataLoadException) {\n                throw (DataLoadException) cause;\n            } else if (cause instanceof RuntimeException) {\n                throw (RuntimeException) cause;\n            } else if (cause instanceof Error) {\n                throw (Error) cause;\n            } else {\n                throw new DataLoadException(\"Unexpected exception during loading\", cause);\n            }\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Preloader preloader = new Preloader();\n        \n        System.out.println(\"Starting preloader...\");\n        preloader.start();\n        \n        System.out.println(\"Doing other work while data loads...\");\n        try {\n            TimeUnit.SECONDS.sleep(1);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Retrieving loaded data...\");\n        try {\n            ProductInfo product = preloader.get();\n            System.out.println(\"Product loaded: \" + product.getName() + \" - $\" + product.getPrice());\n        } catch (DataLoadException e) {\n            System.err.println(\"Failed to load data: \" + e.getMessage());\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            System.err.println(\"Interrupted while waiting for data\");\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.*;\n\n/**\n* Preloader\n*\n* Using FutureTask to preload data that is needed later\n*\n* @author Brian Goetz and Tim Peierls\n*/\npublic class Preloader {\n// Simulate product information loading\nProductInfo loadProductInfo() throws DataLoadException {\ntry {\nThread.sleep(2000); // Simulate loading delay\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\nthrow new DataLoadException();\n}\nreturn new ProductInfoImpl(\"Awesome Product\", 99.99);\n}\n\nprivate final FutureTask<ProductInfo> future =\nnew FutureTask<>(new Callable<ProductInfo>() {\npublic ProductInfo call() throws DataLoadException {\nreturn loadProductInfo();\n}\n});\nprivate final Thread thread = new Thread(future);\n\npublic void start() {\nthread.start();\n}\n\npublic ProductInfo get() throws DataLoadException, InterruptedException {\ntry {\nreturn future.get();\n} catch (ExecutionException e) {\nThrowable cause = e.getCause();\nif (cause instanceof DataLoadException)\nthrow (DataLoadException) cause;\nelse\nthrow LaunderThrowable.launderThrowable(cause);\n}\n}\n\ninterface ProductInfo {\nString getName();\ndouble getPrice();\n}\n\nstatic class ProductInfoImpl implements ProductInfo {\nprivate final String name;\nprivate final double price;\n\npublic ProductInfoImpl(String name, double price) {\nthis.name = name;\nthis.price = price;\n}\n\npublic String getName() {\nreturn name;\n}\n\npublic double getPrice() {\nreturn price;\n}\n\n@Override\npublic String toString() {\nreturn \"ProductInfo{name='\" + name + \"', price=\" + price + \"}\";\n}\n}\n\n// Utility class: for throwing unchecked exceptions\nstatic class LaunderThrowable {\nstatic RuntimeException launderThrowable(Throwable t) {\nif (t instanceof RuntimeException)\nreturn (RuntimeException) t;\nelse if (t instanceof Error)\nthrow (Error) t;\nelse\nthrow new IllegalStateException(\"Not unchecked\", t);\n}\n}\n\n// Main entry point\npublic static void main(String[] args) {\nSystem.out.println(\"Starting preloader...\");\nPreloader preloader = new Preloader();\npreloader.start();\n\ntry {\nSystem.out.println(\"Doing something else in the main thread...\");\nThread.sleep(1000);\n\nSystem.out.println(\"Waiting for product info...\");\nProductInfo productInfo = preloader.get();\nSystem.out.println(\"Loaded product: \" + productInfo);\n} catch (DataLoadException | InterruptedException e) {\ne.printStackTrace();\n}\n}\n}\n\nclass DataLoadException extends Exception {\npublic DataLoadException() {\nsuper(\"Failed to load product data.\");\n}\n}",
        "max_depth": "36",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 46.99%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.32%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=898,visited=713,backtracked=1611,end=135\nsearch:             maxDepth=45,constraints=0\nchoice generators:  thread=893 (signal=0,lock=21,sharedRef=655,threadApi=37,reschedule=141), data=0\nheap:               new=3775,released=3923,maxLive=589,gcCycles=1478\ninstructions:       41881\nmax memory:         981MB\nloaded code:        classes=110,methods=2037\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 47.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=947,visited=757,backtracked=1704,end=140\nsearch:             maxDepth=43,constraints=0\nchoice generators:  thread=942 (signal=0,lock=21,sharedRef=695,threadApi=41,reschedule=146), data=0\nheap:               new=3912,released=4067,maxLive=589,gcCycles=1558\ninstructions:       43531\nmax memory:         981MB\nloaded code:        classes=110,methods=2036\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 47.01%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 44.48%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=947,visited=757,backtracked=1704,end=140\nsearch:             maxDepth=43,constraints=0\nchoice generators:  thread=942 (signal=0,lock=21,sharedRef=695,threadApi=41,reschedule=146), data=0\nheap:               new=3908,released=4063,maxLive=589,gcCycles=1558\ninstructions:       43479\nmax memory:         981MB\nloaded code:        classes=110,methods=2036\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            69.14,
            69.14,
            69.14
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using Semaphore to bound a collection. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a generic BoundedHashSet<T> class in Java that uses a Semaphore to limit the number of elements it can hold. The class should internally use a thread-safe Set<T> (such as Collections.synchronizedSet(new HashSet<>())) and a fixed-size Semaphore initialized with the given bound. The add(T o) method must acquire a permit from the semaphore before attempting to add an element; if the addition fails, the permit should be released back. If successful, the permit is not released — it's considered consumed until the element is removed. The remove(Object o) method should remove the element from the set and release a permit if the removal was successful. Both methods should handle synchronization and resource management correctly.The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 5. Use a fixed thread pool or manually manage at most 4 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass BoundedHashSet<T> {\n    private final Set<T> set;\n    private final Semaphore semaphore;\n    \n    public BoundedHashSet(int bound) {\n        this.set = Collections.synchronizedSet(new HashSet<>());\n        this.semaphore = new Semaphore(bound);\n    }\n    \n    public boolean add(T o) throws InterruptedException {\n        semaphore.acquire();\n        boolean added = set.add(o);\n        if (!added) {\n            semaphore.release();\n        }\n        return added;\n    }\n    \n    public boolean remove(Object o) {\n        boolean removed = set.remove(o);\n        if (removed) {\n            semaphore.release();\n        }\n        return removed;\n    }\n    \n    public int size() {\n        return set.size();\n    }\n    \n    public boolean contains(Object o) {\n        return set.contains(o);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        BoundedHashSet<Integer> boundedSet = new BoundedHashSet<>(5);\n        ExecutorService executor = Executors.newFixedThreadPool(4);\n        CountDownLatch latch = new CountDownLatch(4);\n        \n        Runnable adder1 = () -> {\n            try {\n                for (int i = 0; i < 3; i++) {\n                    boolean added = boundedSet.add(i);\n                    System.out.println(\"Thread 1 added \" + i + \": \" + added);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        };\n        \n        Runnable adder2 = () -> {\n            try {\n                for (int i = 3; i < 6; i++) {\n                    boolean added = boundedSet.add(i);\n                    System.out.println(\"Thread 2 added \" + i + \": \" + added);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        };\n        \n        Runnable remover = () -> {\n            try {\n                Thread.sleep(300);\n                for (int i = 0; i < 3; i++) {\n                    boolean removed = boundedSet.remove(i);\n                    System.out.println(\"Thread 3 removed \" + i + \": \" + removed);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        };\n        \n        Runnable adder3 = () -> {\n            try {\n                Thread.sleep(500);\n                for (int i = 6; i < 9; i++) {\n                    boolean added = boundedSet.add(i);\n                    System.out.println(\"Thread 4 added \" + i + \": \" + added);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        };\n        \n        executor.submit(adder1);\n        executor.submit(adder2);\n        executor.submit(remover);\n        executor.submit(adder3);\n        \n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n        \n        System.out.println(\"Final set size: \" + boundedSet.size());\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass BoundedHashSet<T> {\n    private final Set<T> set;\n    private final Semaphore semaphore;\n    \n    public BoundedHashSet(int bound) {\n        this.set = Collections.synchronizedSet(new HashSet<>());\n        this.semaphore = new Semaphore(bound);\n    }\n    \n    public boolean add(T o) throws InterruptedException {\n        semaphore.acquire();\n        boolean added = set.add(o);\n        if (!added) {\n            semaphore.release();\n        }\n        return added;\n    }\n    \n    public boolean remove(Object o) {\n        boolean removed = set.remove(o);\n        if (removed) {\n            semaphore.release();\n        }\n        return removed;\n    }\n    \n    public int size() {\n        return set.size();\n    }\n    \n    public boolean contains(Object o) {\n        return set.contains(o);\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        BoundedHashSet<Integer> boundedSet = new BoundedHashSet<>(5);\n        ExecutorService executor = Executors.newFixedThreadPool(4);\n        CountDownLatch latch = new CountDownLatch(4);\n        \n        Runnable adder1 = () -> {\n            try {\n                for (int i = 0; i < 3; i++) {\n                    boolean added = boundedSet.add(i);\n                    System.out.println(\"Thread 1 added \" + i + \": \" + added);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        };\n        \n        Runnable adder2 = () -> {\n            try {\n                for (int i = 3; i < 6; i++) {\n                    boolean added = boundedSet.add(i);\n                    System.out.println(\"Thread 2 added \" + i + \": \" + added);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        };\n        \n        Runnable remover = () -> {\n            try {\n                Thread.sleep(300);\n                for (int i = 0; i < 3; i++) {\n                    boolean removed = boundedSet.remove(i);\n                    System.out.println(\"Thread 3 removed \" + i + \": \" + removed);\n                    Thread.sleep(150);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        };\n        \n        Runnable adder3 = () -> {\n            try {\n                Thread.sleep(500);\n                for (int i = 6; i < 9; i++) {\n                    boolean added = boundedSet.add(i);\n                    System.out.println(\"Thread 4 added \" + i + \": \" + added);\n                    Thread.sleep(100);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        };\n        \n        executor.submit(adder1);\n        executor.submit(adder2);\n        executor.submit(remover);\n        executor.submit(adder3);\n        \n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.MINUTES);\n        \n        System.out.println(\"Final set size: \" + boundedSet.size());\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\nclass BoundedHashSet<T> {\n   private final Set<T> set;\n   private final Semaphore semaphore;\n   \n   public BoundedHashSet(int bound) {\n       this.set = Collections.synchronizedSet(new HashSet<T>());\n       this.semaphore = new Semaphore(bound);\n   }\n   \n   public boolean add(T element) {\n       if (element == null) {\n           return false;\n       }\n       if (semaphore.tryAcquire()) {\n           boolean added = set.add(element);\n           if (!added) {\n               semaphore.release();\n           }\n           return added;\n       }\n       return false;\n   }\n   \n   public boolean remove(Object element) {\n       if (element == null) {\n           return false;\n       }\n       boolean removed = set.remove(element);\n       if (removed) {\n           semaphore.release();\n       }\n       return removed;\n   }\n   \n   public int size() {\n       return set.size();\n   }\n   \n   public boolean contains(Object element) {\n       if (element == null) {\n           return false;\n       }\n       return set.contains(element);\n   }\n   \n   public int availablePermits() {\n       return semaphore.availablePermits();\n   }\n}\n\npublic class ConcurrentBoundedSetDemo {\n   \n   public static void main(String[] args) {\n       final BoundedHashSet<Integer> boundedSet = new BoundedHashSet<>(3);\n       \n       Thread thread1 = new Thread(new Runnable() {\n           public void run() {\n               boolean added = boundedSet.add(1);\n               System.out.println(\"Thread 1: Added 1 = \" + added);\n               added = boundedSet.add(2);\n               System.out.println(\"Thread 1: Added 2 = \" + added);\n           }\n       });\n       \n       Thread thread2 = new Thread(new Runnable() {\n           public void run() {\n               boolean added = boundedSet.add(3);\n               System.out.println(\"Thread 2: Added 3 = \" + added);\n               added = boundedSet.add(4);\n               System.out.println(\"Thread 2: Added 4 = \" + added);\n           }\n       });\n       \n       Thread thread3 = new Thread(new Runnable() {\n           public void run() {\n               boolean removed = boundedSet.remove(1);\n               System.out.println(\"Thread 3: Removed 1 = \" + removed);\n               removed = boundedSet.remove(2);\n               System.out.println(\"Thread 3: Removed 2 = \" + removed);\n           }\n       });\n       \n       Thread thread4 = new Thread(new Runnable() {\n           public void run() {\n               boolean added = boundedSet.add(5);\n               System.out.println(\"Thread 4: Added 5 = \" + added);\n               added = boundedSet.add(6);\n               System.out.println(\"Thread 4: Added 6 = \" + added);\n           }\n       });\n       \n       thread1.start();\n       thread2.start();\n       thread3.start();\n       thread4.start();\n       \n       try {\n           thread1.join();\n           thread2.join();\n           thread3.join();\n           thread4.join();\n       } catch (InterruptedException e) {\n           Thread.currentThread().interrupt();\n       }\n       \n       System.out.println(\"Final size: \" + boundedSet.size());\n   }\n}"
        ],
        "graded_list": [
            false,
            false,
            true
        ],
        "ground_truth": "import java.util.Collections;\nimport java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.Semaphore;\n\npublic class BoundedHashSet<T> {\nprivate final Set<T> set;\nprivate final Semaphore sem;\n\npublic BoundedHashSet(int bound) {\nthis.set = Collections.synchronizedSet(new HashSet<>());\nthis.sem = new Semaphore(bound);\n}\n\npublic boolean add(T o) throws InterruptedException {\nsem.acquire();\nboolean added = set.add(o);\nif (!added) {\nsem.release();\n}\nreturn added;\n}\n\npublic boolean remove(Object o) {\nboolean removed = set.remove(o);\nif (removed) {\nsem.release();\n}\nreturn removed;\n}\n\npublic int size() {\nreturn set.size();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal BoundedHashSet<String> boundedSet = new BoundedHashSet<>(2);\n\nThread t1 = new Thread(() -> {\ntry { boundedSet.add(\"A\"); } catch (InterruptedException e) { Thread.currentThread().interrupt(); }\n});\n\nThread t2 = new Thread(() -> {\ntry { boundedSet.add(\"B\"); } catch (InterruptedException e) { Thread.currentThread().interrupt(); }\n});\n\nThread t3 = new Thread(() -> {\ntry { boundedSet.add(\"C\"); } catch (InterruptedException e) { Thread.currentThread().interrupt(); }\n});\n\nt1.start(); t2.start(); t1.join(); t2.join();\n\nboundedSet.remove(\"A\");\n\nt3.start(); t3.join();\n\nSystem.out.println(\"Final set size: \" + boundedSet.size());\n}\n}",
        "max_depth": "27",
        "jpf_details": [
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 0.61%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 12.73%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=165,visited=0,backtracked=0,end=1\nsearch:             maxDepth=165,constraints=0\nchoice generators:  thread=165 (signal=0,lock=15,sharedRef=119,threadApi=14,reschedule=12), data=0\nheap:               new=1132,released=98,maxLive=1033,gcCycles=164\ninstructions:       15367\nmax memory:         981MB\nloaded code:        classes=139,methods=2442\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 0.61%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 12.73%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=165,visited=0,backtracked=0,end=1\nsearch:             maxDepth=165,constraints=0\nchoice generators:  thread=165 (signal=0,lock=15,sharedRef=119,threadApi=14,reschedule=12), data=0\nheap:               new=1132,released=98,maxLive=1033,gcCycles=164\ninstructions:       15367\nmax memory:         981MB\nloaded code:        classes=139,methods=2442\n\n====================================================== search finished",
            "Unique logical threads created during execution: 5\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 51.88%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 40.48%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 45.95%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 46.82%)\n[JPF-STARVATION] Thread ID: 4 OK (waiting proportion: 45.62%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=42824,visited=83118,backtracked=125942,end=85\nsearch:             maxDepth=85,constraints=0\nchoice generators:  thread=42824 (signal=0,lock=8951,sharedRef=14818,threadApi=1165,reschedule=17890), data=0\nheap:               new=537117,released=399381,maxLive=825,gcCycles=125778\ninstructions:       4745589\nmax memory:         1012MB\nloaded code:        classes=101,methods=2010\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"",
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"",
            "no errors detected"
        ],
        "codebleu_score": [
            66.04,
            66.04,
            65.11
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    },
    {
        "prompt_title": "Using a factory method to prevent the this reference from escaping during construction. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called SafeListener that securely registers an event listener with an event source. The class should have a private constructor and a static factory method called newInstance, which takes an EventSource object as a parameter, creates an instance of SafeListener, registers a new EventListener with the provided event source, and returns the created SafeListener instance. The EventListener should be implemented in such a way that when its onEvent method is called, it invokes a method named doSomething on the SafeListener instance. Also include empty definitions for the EventSource, EventListener, and Event interfaces so that the code compiles correctly. Ensure that the listener registration is done safely to prevent leaks or improper access. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SafeListener {\n    private final EventSource eventSource;\n    private volatile boolean active = true;\n    \n    private SafeListener(EventSource eventSource) {\n        this.eventSource = eventSource;\n    }\n    \n    public static SafeListener newInstance(EventSource eventSource) {\n        SafeListener listener = new SafeListener(eventSource);\n        EventListener eventListener = new EventListener() {\n            @Override\n            public void onEvent(Event event) {\n                listener.doSomething(event);\n            }\n        };\n        eventSource.registerListener(eventListener);\n        return listener;\n    }\n    \n    private synchronized void doSomething(Event event) {\n        if (active) {\n            System.out.println(\"Processing event: \" + event);\n        }\n    }\n    \n    public synchronized void deactivate() {\n        active = false;\n    }\n    \n    public static void main(String[] args) {\n        ExecutorService executor = Executors.newSingleThreadExecutor();\n        \n        EventSource source = new EventSource() {\n            private volatile EventListener listener;\n            \n            @Override\n            public void registerListener(EventListener listener) {\n                this.listener = listener;\n            }\n            \n            @Override\n            public void fireEvent(Event event) {\n                EventListener l = this.listener;\n                if (l != null) {\n                    l.onEvent(event);\n                }\n            }\n        };\n        \n        SafeListener safeListener = SafeListener.newInstance(source);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Event event = new Event() {\n                    private final int id = i;\n                    \n                    @Override\n                    public String toString() {\n                        return \"Event-\" + id;\n                    }\n                };\n                source.fireEvent(event);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                    break;\n                }\n            }\n        });\n        \n        try {\n            Thread.sleep(300);\n            safeListener.deactivate();\n            Thread.sleep(300);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\ninterface EventSource {\n    void registerListener(EventListener listener);\n    void fireEvent(Event event);\n}\n\ninterface EventListener {\n    void onEvent(Event event);\n}\n\ninterface Event {\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SafeListener {\n    private final EventSource eventSource;\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    private SafeListener(EventSource eventSource) {\n        this.eventSource = eventSource;\n    }\n    \n    public static SafeListener newInstance(EventSource eventSource) {\n        SafeListener listener = new SafeListener(eventSource);\n        eventSource.registerListener(new EventListener() {\n            @Override\n            public void onEvent(Event event) {\n                listener.doSomething(event);\n            }\n        });\n        return listener;\n    }\n    \n    private void doSomething(Event event) {\n        executor.submit(() -> {\n            System.out.println(\"Processing event: \" + event);\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        EventSource source = new EventSource() {\n            private volatile EventListener listener;\n            \n            @Override\n            public void registerListener(EventListener listener) {\n                this.listener = listener;\n            }\n            \n            @Override\n            public void fireEvent(Event event) {\n                EventListener l = this.listener;\n                if (l != null) {\n                    l.onEvent(event);\n                }\n            }\n        };\n        \n        SafeListener safeListener = SafeListener.newInstance(source);\n        \n        source.fireEvent(new Event() {});\n        source.fireEvent(new Event() {});\n        source.fireEvent(new Event() {});\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        safeListener.shutdown();\n    }\n}\n\ninterface EventSource {\n    void registerListener(EventListener listener);\n    void fireEvent(Event event);\n}\n\ninterface EventListener {\n    void onEvent(Event event);\n}\n\ninterface Event {\n}",
            "import java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class SafeListener {\n    private final EventSource eventSource;\n    private final ExecutorService executor = Executors.newSingleThreadExecutor();\n    \n    private SafeListener(EventSource eventSource) {\n        this.eventSource = eventSource;\n    }\n    \n    public static SafeListener newInstance(EventSource eventSource) {\n        SafeListener listener = new SafeListener(eventSource);\n        EventListener eventListener = new EventListener() {\n            @Override\n            public void onEvent(Event event) {\n                listener.doSomething(event);\n            }\n        };\n        eventSource.registerListener(eventListener);\n        return listener;\n    }\n    \n    private void doSomething(Event event) {\n        executor.execute(() -> {\n            System.out.println(\"Processing event: \" + event);\n        });\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n    \n    public static void main(String[] args) {\n        EventSource source = new EventSource() {\n            private volatile EventListener listener;\n            \n            @Override\n            public void registerListener(EventListener listener) {\n                this.listener = listener;\n            }\n            \n            @Override\n            public void fireEvent(Event event) {\n                EventListener l = listener;\n                if (l != null) {\n                    l.onEvent(event);\n                }\n            }\n        };\n        \n        SafeListener safeListener = SafeListener.newInstance(source);\n        \n        source.fireEvent(new Event() {\n            @Override\n            public String toString() {\n                return \"Event1\";\n            }\n        });\n        \n        source.fireEvent(new Event() {\n            @Override\n            public String toString() {\n                return \"Event2\";\n            }\n        });\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        safeListener.shutdown();\n    }\n}\n\ninterface EventSource {\n    void registerListener(EventListener listener);\n    void fireEvent(Event event);\n}\n\ninterface EventListener {\n    void onEvent(Event event);\n}\n\ninterface Event {\n}"
        ],
        "graded_list": [
            false,
            true,
            true
        ],
        "ground_truth": "import java.util.concurrent.CopyOnWriteArrayList;\n\npublic class SafeListener {\nprivate SafeListener(EventSource source) {\nsource.registerListener(new EventListener() {\n@Override\npublic void onEvent(Event e) {\ndoSomething();\n}\n});\n}\n\npublic static SafeListener newInstance(EventSource source) {\nreturn new SafeListener(source);\n}\n\nprivate synchronized void doSomething() {\nSystem.out.println(\"SafeListener is doing something.\");\n}\n\npublic static void main(String[] args) throws InterruptedException {\nEventSource source = new EventSource();\n\nSafeListener listener = SafeListener.newInstance(source);\n\nThread eventThread = new Thread(() -> {\nfor (int i = 0; i < 3; i++) {\nsource.fireEvent(new Event() {});\ntry {\nThread.sleep(100);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n\neventThread.start();\neventThread.join();\n}\n}\n\nclass EventSource {\nprivate final CopyOnWriteArrayList<EventListener> listeners = new CopyOnWriteArrayList<>();\n\npublic void registerListener(EventListener listener) {\nlisteners.add(listener);\n}\n\npublic void fireEvent(Event event) {\nfor (EventListener listener : listeners) {\nlistener.onEvent(event);\n}\n}\n}\n\ninterface EventListener {\nvoid onEvent(Event e);\n}\n\ninterface Event {}",
        "max_depth": "15",
        "jpf_details": [
            "./temp_compile/SafeListener.java:60: error: local variables referenced from an inner class must be final or effectively final\n                    private final int id = i;\n                                           ^\n1 error",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.61%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 33.56%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=125568,visited=61984,backtracked=187479,end=61424\nsearch:             maxDepth=150,constraints=1578\nchoice generators:  thread=124515 (signal=0,lock=29,sharedRef=526,threadApi=2,reschedule=61450), data=0\nheap:               new=736100,released=3856204,maxLive=753,gcCycles=187552\ninstructions:       98535579\nmax memory:         1018MB\nloaded code:        classes=146,methods=2438\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.93%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 33.40%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=16266,visited=8105,backtracked=24371,end=7811\nsearch:             maxDepth=150,constraints=239\nchoice generators:  thread=16105 (signal=0,lock=42,sharedRef=4820,threadApi=5,reschedule=7843), data=0\nheap:               new=83532,released=391729,maxLive=738,gcCycles=24371\ninstructions:       9105302\nmax memory:         981MB\nloaded code:        classes=144,methods=2445\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "syntax error",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            61.82,
            63.05,
            62.95
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Using a volatile field to hold cancellation state. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write a Java program that generates 10 prime numbers in a separate thread for a duration of one second, then cancels the generation and returns the list of found primes. Use a volatile variable to manage the cancellation state, ensure thread-safe access to the shared list of primes, and utilize an ExecutorService to run the task in a separate thread. The program should include a method to retrieve the collected prime numbers and properly cancel the computation after one second has elapsed. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 2. Use a fixed thread pool or manually manage at most 1 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PrimeGenerator {\n    \n    private volatile boolean cancelled = false;\n    private final List<Integer> primes = Collections.synchronizedList(new ArrayList<>());\n    \n    public void generatePrimes() {\n        int num = 2;\n        while (!cancelled) {\n            if (isPrime(num)) {\n                primes.add(num);\n            }\n            num++;\n        }\n    }\n    \n    private boolean isPrime(int n) {\n        if (n <= 1) return false;\n        if (n <= 3) return true;\n        if (n % 2 == 0 || n % 3 == 0) return false;\n        for (int i = 5; i * i <= n; i += 6) {\n            if (n % i == 0 || n % (i + 2) == 0) {\n                return false;\n            }\n        }\n        return true;\n    }\n    \n    public void cancel() {\n        cancelled = true;\n    }\n    \n    public List<Integer> getPrimes() {\n        return new ArrayList<>(primes);\n    }\n    \n    public static void main(String[] args) {\n        PrimeGenerator generator = new PrimeGenerator();\n        ExecutorService executor = Executors.newSingleThreadExecutor();\n        \n        Future<?> future = executor.submit(() -> generator.generatePrimes());\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        generator.cancel();\n        \n        try {\n            future.get(100, TimeUnit.MILLISECONDS);\n        } catch (InterruptedException | ExecutionException | TimeoutException e) {\n            future.cancel(true);\n        }\n        \n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(100, TimeUnit.MILLISECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        List<Integer> foundPrimes = generator.getPrimes();\n        System.out.println(\"Found \" + foundPrimes.size() + \" prime numbers\");\n        System.out.println(\"Primes: \" + foundPrimes);\n    }\n}",
            "import java.util.ArrayList;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PrimeGenerator {\n    private volatile boolean cancelled = false;\n    private final List<Integer> primes = Collections.synchronizedList(new ArrayList<>());\n    \n    public void generatePrimes() {\n        int number = 2;\n        while (!cancelled) {\n            if (isPrime(number)) {\n                primes.add(number);\n            }\n            number++;\n        }\n    }\n    \n    private boolean isPrime(int n) {\n        if (n <= 1) return false;\n        if (n <= 3) return true;\n        if (n % 2 == 0 || n % 3 == 0) return false;\n        for (int i = 5; i * i <= n; i += 6) {\n            if (n % i == 0 || n % (i + 2) == 0) return false;\n        }\n        return true;\n    }\n    \n    public void cancel() {\n        cancelled = true;\n    }\n    \n    public List<Integer> getPrimes() {\n        return new ArrayList<>(primes);\n    }\n    \n    public static void main(String[] args) {\n        PrimeGenerator generator = new PrimeGenerator();\n        ExecutorService executor = Executors.newSingleThreadExecutor();\n        \n        executor.submit(() -> generator.generatePrimes());\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        generator.cancel();\n        executor.shutdown();\n        \n        try {\n            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n        \n        List<Integer> foundPrimes = generator.getPrimes();\n        System.out.println(\"Found \" + foundPrimes.size() + \" prime numbers\");\n        System.out.println(\"First 10 primes: \" + foundPrimes.subList(0, Math.min(10, foundPrimes.size())));\n        System.out.println(\"Last prime found: \" + (foundPrimes.isEmpty() ? \"None\" : foundPrimes.get(foundPrimes.size() - 1)));\n    }\n}",
            "import java.util.ArrayList;\nimport java.util.Collections;\nimport java.util.List;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PrimeGenerator {\n    private volatile boolean cancelled = false;\n    private final List<Integer> primes = Collections.synchronizedList(new ArrayList<>());\n    \n    private boolean isPrime(int n) {\n        if (n <= 1) return false;\n        if (n <= 3) return true;\n        if (n % 2 == 0 || n % 3 == 0) return false;\n        for (int i = 5; i * i <= n; i += 6) {\n            if (n % i == 0 || n % (i + 2) == 0) return false;\n        }\n        return true;\n    }\n    \n    private void generatePrimes() {\n        int number = 2;\n        while (!cancelled) {\n            if (isPrime(number)) {\n                primes.add(number);\n            }\n            number++;\n        }\n    }\n    \n    public List<Integer> getPrimes() {\n        return new ArrayList<>(primes);\n    }\n    \n    public void cancel() {\n        cancelled = true;\n    }\n    \n    public static void main(String[] args) {\n        PrimeGenerator generator = new PrimeGenerator();\n        ExecutorService executor = Executors.newSingleThreadExecutor();\n        \n        executor.submit(() -> generator.generatePrimes());\n        \n        try {\n            Thread.sleep(1000);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        generator.cancel();\n        executor.shutdown();\n        \n        try {\n            executor.awaitTermination(1, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        List<Integer> foundPrimes = generator.getPrimes();\n        System.out.println(\"Found \" + foundPrimes.size() + \" prime numbers\");\n        System.out.println(\"Primes: \" + foundPrimes);\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.math.BigInteger;\nimport java.util.*;\n\npublic class PrimeGenerator implements Runnable {\nprivate final List<BigInteger> primes = new ArrayList<>();\nprivate volatile boolean cancelled = false;\nprivate final int maxPrimes;\n\npublic PrimeGenerator(int maxPrimes) {\nthis.maxPrimes = maxPrimes;\n}\n\npublic void run() {\nBigInteger p = BigInteger.ONE;\nwhile (!cancelled && primes.size() < maxPrimes) {\np = p.nextProbablePrime();\nsynchronized (this) {\nprimes.add(p);\n}\n// Optional: remove sleep to speed up, or keep a very short sleep\ntry {\nThread.sleep(1);\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\nbreak;\n}\n}\n}\n\npublic void cancel() {\ncancelled = true;\n}\n\npublic synchronized List<BigInteger> get() {\nreturn new ArrayList<>(primes);\n}\n\npublic static List<BigInteger> generatePrimes(int count) throws InterruptedException {\nPrimeGenerator generator = new PrimeGenerator(count);\nThread thread = new Thread(generator);\nthread.start();\nthread.join(); // Wait until generator finishes generating count primes\nreturn generator.get();\n}\n\npublic static void main(String[] args) {\ntry {\nint primeCount = 10; // Generate 10 primes\nList<BigInteger> primes = generatePrimes(primeCount);\n\nSystem.out.println(\"Generated \" + primes.size() + \" primes.\");\n\nint limit = Math.min(10, primes.size());\nSystem.out.println(\"First \" + limit + \" primes:\");\nfor (int i = 0; i < limit; i++) {\nSystem.out.println(primes.get(i));\n}\n} catch (InterruptedException e) {\nSystem.err.println(\"Interrupted during prime generation: \" + e.getMessage());\nThread.currentThread().interrupt();\n}\n}\n}",
        "max_depth": "213",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.02%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 32.83%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=115346,visited=56734,backtracked=170297,end=56649\nsearch:             maxDepth=2130,constraints=117\nchoice generators:  thread=115266 (signal=0,lock=30,sharedRef=88,threadApi=2,reschedule=56655), data=0\nheap:               new=2091575,released=3355052,maxLive=749,gcCycles=172080\ninstructions:       79440722\nmax memory:         1010MB\nloaded code:        classes=150,methods=2724\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.30%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 32.31%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=107986,visited=53826,backtracked=161259,end=53522\nsearch:             maxDepth=2130,constraints=75\nchoice generators:  thread=107936 (signal=0,lock=33,sharedRef=170,threadApi=2,reschedule=53546), data=0\nheap:               new=2358420,released=3481494,maxLive=748,gcCycles=161812\ninstructions:       79127300\nmax memory:         1006MB\nloaded code:        classes=145,methods=2716\n\n====================================================== search finished",
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 33.10%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 32.86%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=124254,visited=61386,backtracked=183941,end=61073\nsearch:             maxDepth=2130,constraints=84\nchoice generators:  thread=124198 (signal=0,lock=35,sharedRef=173,threadApi=2,reschedule=61099), data=0\nheap:               new=1652180,released=3544553,maxLive=738,gcCycles=185640\ninstructions:       80716130\nmax memory:         1009MB\nloaded code:        classes=143,methods=2684\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            53.69,
            60.99,
            60.17
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using confinement to ensure thread safety. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a thread-safe Java class called PersonSet that uses synchronization to ensure safe concurrent access to a set of Person objects. The class should encapsulate a Set<Person> variable, initialized as a HashSet. It should provide two synchronized methods: one to add a Person object to the set, and another to check if the set contains a specific Person object. Additionally, define the Person interface as a nested type within the class. Ensure that the internal set is guarded by the object's intrinsic lock (i.e., this) to prevent race conditions in a multi-threaded environment. Use appropriate annotations from the net.jcip.annotations package to indicate that the class is thread-safe. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword.\nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else.\nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PersonSet {\n    private final Set<Person> personSet = new HashSet<>();\n    \n    public synchronized boolean addPerson(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Thread 1 added: \" + person.getName());\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 5; i < 10; i++) {\n                Person person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Thread 2 added: \" + person.getName());\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n        \n        Person checkPerson = new PersonImpl(\"Person3\", 23);\n        boolean contains = personSet.containsPerson(checkPerson);\n        System.out.println(\"Contains Person3: \" + contains);\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    @Override\n    public String getName() {\n        return name;\n    }\n    \n    @Override\n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object o) {\n        if (this == o) return true;\n        if (o == null || getClass() != o.getClass()) return false;\n        PersonImpl person = (PersonImpl) o;\n        return age == person.age && Objects.equals(name, person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return Objects.hash(name, age);\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    private final Set<Person> personSet;\n    \n    public PersonSet() {\n        this.personSet = new HashSet<>();\n    }\n    \n    public synchronized boolean addPerson(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public static void main(String[] args) {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Thread 1 added: \" + person.getName());\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 3; i < 8; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean contains = personSet.containsPerson(person);\n                System.out.println(\"Thread 2 checking Person\" + i + \": \" + contains);\n                if (!contains) {\n                    personSet.addPerson(person);\n                    System.out.println(\"Thread 2 added: \" + person.getName());\n                }\n                try {\n                    Thread.sleep(150);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.shutdown();\n        try {\n            executor.awaitTermination(5, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        \n        System.out.println(\"Final set size: \" + personSet.personSet.size());\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}",
            "import java.util.HashSet;\nimport java.util.Set;\nimport java.util.concurrent.ExecutorService;\nimport java.util.concurrent.Executors;\nimport java.util.concurrent.TimeUnit;\n\npublic class PersonSet {\n    private final Set<Person> personSet = new HashSet<>();\n    \n    public synchronized boolean addPerson(Person person) {\n        return personSet.add(person);\n    }\n    \n    public synchronized boolean containsPerson(Person person) {\n        return personSet.contains(person);\n    }\n    \n    public interface Person {\n        String getName();\n        int getAge();\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        PersonSet personSet = new PersonSet();\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                personSet.addPerson(person);\n                System.out.println(\"Added: \" + person.getName());\n            }\n        });\n        \n        executor.submit(() -> {\n            try {\n                Thread.sleep(100);\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n            for (int i = 0; i < 7; i++) {\n                PersonImpl person = new PersonImpl(\"Person\" + i, 20 + i);\n                boolean contains = personSet.containsPerson(person);\n                System.out.println(\"Contains \" + person.getName() + \": \" + contains);\n            }\n        });\n        \n        executor.shutdown();\n        executor.awaitTermination(5, TimeUnit.SECONDS);\n    }\n}\n\nclass PersonImpl implements PersonSet.Person {\n    private final String name;\n    private final int age;\n    \n    public PersonImpl(String name, int age) {\n        this.name = name;\n        this.age = age;\n    }\n    \n    public String getName() {\n        return name;\n    }\n    \n    public int getAge() {\n        return age;\n    }\n    \n    @Override\n    public boolean equals(Object obj) {\n        if (this == obj) return true;\n        if (obj == null || getClass() != obj.getClass()) return false;\n        PersonImpl person = (PersonImpl) obj;\n        return age == person.age && name.equals(person.name);\n    }\n    \n    @Override\n    public int hashCode() {\n        return 31 * name.hashCode() + age;\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\n\n/**\n* PersonSet\n*\n* A thread-safe set using synchronized methods,\n* adapted to be compatible with Java Pathfinder (JPF).\n*/\npublic class PersonSet {\nprivate final Set<Person> mySet = new HashSet<>();\n\npublic synchronized void addPerson(Person p) {\nmySet.add(p);\n}\n\npublic synchronized boolean containsPerson(Person p) {\nreturn mySet.contains(p);\n}\n\npublic interface Person {\nString getName();\n}\n\npublic static class SimplePerson implements Person {\nprivate final String name;\n\npublic SimplePerson(String name) {\nthis.name = name;\n}\n\n@Override\npublic String getName() {\nreturn name;\n}\n\n@Override\npublic boolean equals(Object o) {\nif (this == o) return true;\nif (!(o instanceof SimplePerson)) return false;\nSimplePerson that = (SimplePerson) o;\nreturn Objects.equals(name, that.name);\n}\n\n@Override\npublic int hashCode() {\nreturn Objects.hash(name);\n}\n\n@Override\npublic String toString() {\nreturn \"Person{name='\" + name + \"'}\";\n}\n}\n\npublic static void main(String[] args) throws InterruptedException {\nPersonSet personSet = new PersonSet();\n\nThread t1 = new Thread(() -> {\nPerson p = new SimplePerson(\"Alice\");\npersonSet.addPerson(p);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + p);\n});\n\nThread t2 = new Thread(() -> {\nPerson p = new SimplePerson(\"Bob\");\npersonSet.addPerson(p);\nSystem.out.println(Thread.currentThread().getName() + \" added: \" + p);\n});\n\nt1.start();\nt2.start();\n\nt1.join();\nt2.join();\n\nList<String> checkNames = Arrays.asList(\"Alice\", \"Frank\");\nfor (String name : checkNames) {\nPerson p = new SimplePerson(name);\nSystem.out.println(p.getName() + \" is in set? \" + personSet.containsPerson(p));\n}\n\nSystem.out.println(\"Program completed.\");\n}\n}",
        "max_depth": "31",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.06%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 63.98%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.24%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=141463,visited=94387,backtracked=235553,end=0\nsearch:             maxDepth=310,constraints=68422\nchoice generators:  thread=82434 (signal=0,lock=13604,sharedRef=54171,threadApi=2,reschedule=2586), data=0\nheap:               new=697825,released=172635,maxLive=1038,gcCycles=233714\ninstructions:       25189776\nmax memory:         1019MB\nloaded code:        classes=139,methods=2598\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.37%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.32%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=156973,visited=118026,backtracked=274689,end=0\nsearch:             maxDepth=310,constraints=70718\nchoice generators:  thread=96290 (signal=0,lock=18604,sharedRef=54267,threadApi=7806,reschedule=3520), data=0\nheap:               new=641746,released=309494,maxLive=773,gcCycles=272514\ninstructions:       29410277\nmax memory:         1019MB\nloaded code:        classes=138,methods=2418\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 64.98%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 64.04%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=160000,visited=131552,backtracked=291259,end=2\nsearch:             maxDepth=310,constraints=67998\nchoice generators:  thread=101938 (signal=0,lock=20133,sharedRef=63185,threadApi=2307,reschedule=3914), data=0\nheap:               new=375915,released=648236,maxLive=759,gcCycles=290223\ninstructions:       31697747\nmax memory:         1020MB\nloaded code:        classes=138,methods=2418\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            56.63,
            52.59,
            53.65
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Using interruption for cancellation. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: \"Write a Java 8 program that uses a BlockingQueue to implement a producer-consumer pattern for generating and consuming prime numbers. The program should: \n\nDefine a PrimeProducer class that extends Thread.\nThe producer should generate 2 prime numbers and put them into the queue.\nIt should stop when it has produced the requested number of primes or if interrupted.\nA consumer thread should read from the same queue, print each prime number as it is consumed, and stop after processing all generated primes.\nThe main method should start both threads, wait for the consumer to finish, then signal the producer to stop and wait for it to finish.\nUse proper error handling for interruptions.\nMake sure the code is thread-safe and uses Java 8 features appropriately.\" \nEnsure proper handling of thread interruption to allow clean termination. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.math.BigInteger;\nimport java.util.concurrent.BlockingQueue;\nimport java.util.concurrent.LinkedBlockingQueue;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicBoolean;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class PrimeProducerConsumer {\n    public static void main(String[] args) {\n        int numberOfPrimes = 10;\n        BlockingQueue<BigInteger> queue = new LinkedBlockingQueue<>();\n        AtomicBoolean producerFinished = new AtomicBoolean(false);\n        AtomicInteger primesConsumed = new AtomicInteger(0);\n        \n        PrimeProducer producer = new PrimeProducer(queue, numberOfPrimes, producerFinished);\n        \n        Thread consumer = new Thread(() -> {\n            try {\n                while (primesConsumed.get() < numberOfPrimes) {\n                    BigInteger prime = queue.poll(100, TimeUnit.MILLISECONDS);\n                    if (prime != null) {\n                        System.out.println(\"Consumed prime: \" + prime);\n                        primesConsumed.incrementAndGet();\n                    } else if (producerFinished.get()) {\n                        break;\n                    }\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        producer.start();\n        consumer.start();\n        \n        try {\n            consumer.join();\n            producer.interrupt();\n            producer.join();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PrimeProducer extends Thread {\n    private final BlockingQueue<BigInteger> queue;\n    private final int numberOfPrimes;\n    private final AtomicBoolean finished;\n    \n    public PrimeProducer(BlockingQueue<BigInteger> queue, int numberOfPrimes, AtomicBoolean finished) {\n        this.queue = queue;\n        this.numberOfPrimes = numberOfPrimes;\n        this.finished = finished;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            BigInteger prime = BigInteger.valueOf(2);\n            for (int i = 0; i < numberOfPrimes && !Thread.currentThread().isInterrupted(); i++) {\n                prime = prime.nextProbablePrime();\n                queue.put(prime);\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        } finally {\n            finished.set(true);\n        }\n    }\n}",
            "import java.math.BigInteger;\nimport java.util.concurrent.BlockingQueue;\nimport java.util.concurrent.LinkedBlockingQueue;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicBoolean;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class PrimeProducerConsumer {\n    \n    public static void main(String[] args) {\n        BlockingQueue<BigInteger> queue = new LinkedBlockingQueue<>();\n        int numberOfPrimes = 10;\n        AtomicInteger consumedCount = new AtomicInteger(0);\n        AtomicBoolean producerFinished = new AtomicBoolean(false);\n        \n        PrimeProducer producer = new PrimeProducer(queue, numberOfPrimes, producerFinished);\n        \n        Thread consumer = new Thread(() -> {\n            try {\n                while (consumedCount.get() < numberOfPrimes) {\n                    BigInteger prime = queue.poll(100, TimeUnit.MILLISECONDS);\n                    if (prime != null) {\n                        System.out.println(\"Consumed: \" + prime);\n                        consumedCount.incrementAndGet();\n                    } else if (producerFinished.get() && queue.isEmpty()) {\n                        break;\n                    }\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        producer.start();\n        consumer.start();\n        \n        try {\n            consumer.join();\n            producer.interrupt();\n            producer.join();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PrimeProducer extends Thread {\n    private final BlockingQueue<BigInteger> queue;\n    private final int numberOfPrimes;\n    private final AtomicBoolean finished;\n    \n    public PrimeProducer(BlockingQueue<BigInteger> queue, int numberOfPrimes, AtomicBoolean finished) {\n        this.queue = queue;\n        this.numberOfPrimes = numberOfPrimes;\n        this.finished = finished;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            BigInteger prime = BigInteger.valueOf(2);\n            int count = 0;\n            \n            while (count < numberOfPrimes && !Thread.currentThread().isInterrupted()) {\n                prime = prime.nextProbablePrime();\n                queue.put(prime);\n                count++;\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        } finally {\n            finished.set(true);\n        }\n    }\n}",
            "import java.math.BigInteger;\nimport java.util.concurrent.BlockingQueue;\nimport java.util.concurrent.LinkedBlockingQueue;\nimport java.util.concurrent.TimeUnit;\nimport java.util.concurrent.atomic.AtomicBoolean;\nimport java.util.concurrent.atomic.AtomicInteger;\n\npublic class PrimeProducerConsumer {\n    \n    public static void main(String[] args) {\n        final int numberOfPrimes = 10;\n        BlockingQueue<BigInteger> queue = new LinkedBlockingQueue<>();\n        AtomicBoolean producerFinished = new AtomicBoolean(false);\n        AtomicInteger consumedCount = new AtomicInteger(0);\n        \n        PrimeProducer producer = new PrimeProducer(queue, numberOfPrimes, producerFinished);\n        \n        Thread consumer = new Thread(() -> {\n            try {\n                while (consumedCount.get() < numberOfPrimes) {\n                    BigInteger prime = queue.poll(100, TimeUnit.MILLISECONDS);\n                    if (prime != null) {\n                        System.out.println(\"Consumed prime: \" + prime);\n                        consumedCount.incrementAndGet();\n                    } else if (producerFinished.get() && queue.isEmpty()) {\n                        break;\n                    }\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            }\n        });\n        \n        producer.start();\n        consumer.start();\n        \n        try {\n            consumer.join();\n            producer.interrupt();\n            producer.join();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass PrimeProducer extends Thread {\n    private final BlockingQueue<BigInteger> queue;\n    private final int numberOfPrimes;\n    private final AtomicBoolean finished;\n    \n    public PrimeProducer(BlockingQueue<BigInteger> queue, int numberOfPrimes, AtomicBoolean finished) {\n        this.queue = queue;\n        this.numberOfPrimes = numberOfPrimes;\n        this.finished = finished;\n    }\n    \n    @Override\n    public void run() {\n        try {\n            BigInteger prime = BigInteger.valueOf(2);\n            for (int i = 0; i < numberOfPrimes && !Thread.currentThread().isInterrupted(); i++) {\n                prime = prime.nextProbablePrime();\n                queue.put(prime);\n            }\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        } finally {\n            finished.set(true);\n        }\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.math.BigInteger;\nimport java.util.concurrent.BlockingQueue;\nimport java.util.concurrent.LinkedBlockingQueue;\n\npublic class PrimeProducer extends Thread {\nprivate final BlockingQueue<BigInteger> queue;\nprivate final int maxPrimesToGenerate;\n\npublic PrimeProducer(BlockingQueue<BigInteger> queue, int maxPrimesToGenerate) {\nthis.queue = queue;\nthis.maxPrimesToGenerate = maxPrimesToGenerate;\n}\n\n@Override\npublic void run() {\ntry {\nBigInteger p = BigInteger.ONE;\nint count = 0;\nwhile (!Thread.currentThread().isInterrupted() && count < maxPrimesToGenerate) {\np = p.nextProbablePrime();\nqueue.put(p);\ncount++;\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n\npublic void cancel() {\ninterrupt();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nBlockingQueue<BigInteger> queue = new LinkedBlockingQueue<>();\nfinal int primesToProduce = 2;\n\nPrimeProducer producer = new PrimeProducer(queue, primesToProduce);\nproducer.start();\n\nThread consumer = new Thread(() -> {\nint count = 0;\ntry {\nwhile (count < primesToProduce) {\nBigInteger prime = queue.take();\nSystem.out.println(\"Consumed: \" + prime);\ncount++;\n}\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\nSystem.out.println(\"Consumer was interrupted.\");\n}\n});\n\nconsumer.start();\nconsumer.join();\n\nproducer.cancel();\nproducer.join();\n\nSystem.out.println(\"All tasks completed.\");\n}\n}",
        "max_depth": "71",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 27.84%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 35.89%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 35.34%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=74002,visited=40468,backtracked=113863,end=6\nsearch:             maxDepth=710,constraints=462\nchoice generators:  thread=73693 (signal=0,lock=167,sharedRef=11169,threadApi=45,reschedule=32992), data=0\nheap:               new=747557,released=906135,maxLive=1074,gcCycles=114262\ninstructions:       65336484\nmax memory:         1019MB\nloaded code:        classes=119,methods=2681\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 27.84%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 35.89%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 35.34%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=74055,visited=40493,backtracked=113884,end=6\nsearch:             maxDepth=710,constraints=465\nchoice generators:  thread=73742 (signal=0,lock=167,sharedRef=11029,threadApi=45,reschedule=33015), data=0\nheap:               new=714990,released=873490,maxLive=1074,gcCycles=114340\ninstructions:       65414008\nmax memory:         1019MB\nloaded code:        classes=119,methods=2681\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 28.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 35.82%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 35.27%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=76361,visited=41651,backtracked=117365,end=6\nsearch:             maxDepth=710,constraints=465\nchoice generators:  thread=76049 (signal=0,lock=167,sharedRef=11231,threadApi=45,reschedule=34166), data=0\nheap:               new=769469,released=933866,maxLive=1074,gcCycles=117804\ninstructions:       66328465\nmax memory:         1019MB\nloaded code:        classes=119,methods=2681\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            65.45,
            65.29,
            62.67
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Vehicle tracker that safely publishes underlying state. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called PublishingVehicleTracker that manages the locations of vehicles in a thread-safe manner. The class should allow safe publication of its internal state to prevent unintended modifications from external code. Use a thread-safe map implementation to store vehicle locations, where each entry maps a vehicle ID (String) to a SafePoint object that represents its current coordinates. Provide an unmodifiable view of the full location map for external access. Include methods to retrieve the full map of vehicle locations, get the location of a specific vehicle by ID, and update the location of a vehicle by setting its x and y coordinates. Ensure that attempting to update a non-existent vehicle throws an appropriate exception. The design should follow best practices for encapsulation and thread safety. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> initialLocations) {\n        this.locations = new ConcurrentHashMap<>(initialLocations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint location = locations.get(id);\n        if (location == null) {\n            throw new IllegalArgumentException(\"Vehicle ID not found: \" + id);\n        }\n        location.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle3\", new SafePoint(30, 40));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 10, i * 20);\n                System.out.println(\"Thread 1 updated vehicle1 to: \" + tracker.getLocation(\"vehicle1\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 5, i * 15);\n                System.out.println(\"Thread 2 updated vehicle2 to: \" + tracker.getLocation(\"vehicle2\"));\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        System.out.println(\"Main thread - All locations: \" + tracker.getLocations());\n\n        executor.shutdown();\n        executor.awaitTermination(2, TimeUnit.SECONDS);\n\n        System.out.println(\"Final locations:\");\n        for (Map.Entry<String, SafePoint> entry : tracker.getLocations().entrySet()) {\n            System.out.println(entry.getKey() + \": \" + entry.getValue());\n        }\n    }\n}\n\nclass SafePoint {\n    private int x;\n    private int y;\n\n    public SafePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public SafePoint(SafePoint p) {\n        this(p.get()[0], p.get()[1]);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public synchronized String toString() {\n        return \"[\" + x + \", \" + y + \"]\";\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n\n    public PublishingVehicleTracker(Map<String, SafePoint> initialLocations) {\n        this.locations = new ConcurrentHashMap<>(initialLocations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n\n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n\n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n\n    public void setLocation(String id, int x, int y) {\n        SafePoint location = locations.get(id);\n        if (location == null) {\n            throw new IllegalArgumentException(\"Vehicle with ID \" + id + \" does not exist\");\n        }\n        location.set(x, y);\n    }\n\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initialLocations = new HashMap<>();\n        initialLocations.put(\"vehicle1\", new SafePoint(0, 0));\n        initialLocations.put(\"vehicle2\", new SafePoint(10, 20));\n        initialLocations.put(\"vehicle3\", new SafePoint(30, 40));\n\n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initialLocations);\n\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                SafePoint point = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"Thread 1 - Vehicle1: \" + point);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 5, i * 7);\n                SafePoint point = tracker.getLocation(\"vehicle2\");\n                System.out.println(\"Thread 2 - Vehicle2: \" + point);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        Thread.sleep(200);\n        \n        Map<String, SafePoint> allLocations = tracker.getLocations();\n        System.out.println(\"Main thread - All locations: \" + allLocations);\n\n        try {\n            tracker.setLocation(\"nonexistent\", 0, 0);\n        } catch (IllegalArgumentException e) {\n            System.out.println(\"Main thread - Exception caught: \" + e.getMessage());\n        }\n\n        executor.shutdown();\n        executor.awaitTermination(2, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x;\n    private int y;\n\n    public SafePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public SafePoint(SafePoint point) {\n        this(point.x, point.y);\n    }\n\n    public synchronized int[] get() {\n        return new int[]{x, y};\n    }\n\n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n\n    public synchronized String toString() {\n        return \"[\" + x + \", \" + y + \"]\";\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\n    private final ConcurrentHashMap<String, SafePoint> locations;\n    private final Map<String, SafePoint> unmodifiableMap;\n    \n    public PublishingVehicleTracker(Map<String, SafePoint> initialLocations) {\n        this.locations = new ConcurrentHashMap<>(initialLocations);\n        this.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n    }\n    \n    public Map<String, SafePoint> getLocations() {\n        return unmodifiableMap;\n    }\n    \n    public SafePoint getLocation(String id) {\n        return locations.get(id);\n    }\n    \n    public void setLocation(String id, int x, int y) {\n        SafePoint point = locations.get(id);\n        if (point == null) {\n            throw new IllegalArgumentException(\"Vehicle not found: \" + id);\n        }\n        point.set(x, y);\n    }\n    \n    public static void main(String[] args) throws InterruptedException {\n        Map<String, SafePoint> initial = new HashMap<>();\n        initial.put(\"vehicle1\", new SafePoint(0, 0));\n        initial.put(\"vehicle2\", new SafePoint(10, 10));\n        initial.put(\"vehicle3\", new SafePoint(20, 20));\n        \n        PublishingVehicleTracker tracker = new PublishingVehicleTracker(initial);\n        ExecutorService executor = Executors.newFixedThreadPool(2);\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle1\", i * 2, i * 3);\n                SafePoint loc = tracker.getLocation(\"vehicle1\");\n                System.out.println(\"Thread 1 - Vehicle1: \" + loc);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        executor.submit(() -> {\n            for (int i = 0; i < 5; i++) {\n                tracker.setLocation(\"vehicle2\", i * 4, i * 5);\n                SafePoint loc = tracker.getLocation(\"vehicle2\");\n                System.out.println(\"Thread 2 - Vehicle2: \" + loc);\n                try {\n                    Thread.sleep(100);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n        \n        Thread.sleep(200);\n        Map<String, SafePoint> allLocations = tracker.getLocations();\n        System.out.println(\"Main thread - All locations: \" + allLocations);\n        \n        executor.shutdown();\n        executor.awaitTermination(10, TimeUnit.SECONDS);\n    }\n}\n\nclass SafePoint {\n    private int x;\n    private int y;\n    \n    public SafePoint(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public SafePoint(SafePoint p) {\n        this(p.get());\n    }\n    \n    public SafePoint(int[] coords) {\n        this(coords[0], coords[1]);\n    }\n    \n    public synchronized int[] get() {\n        return new int[] {x, y};\n    }\n    \n    public synchronized void set(int x, int y) {\n        this.x = x;\n        this.y = y;\n    }\n    \n    public String toString() {\n        int[] coords = get();\n        return \"[x=\" + coords[0] + \", y=\" + coords[1] + \"]\";\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            true
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\npublic class PublishingVehicleTracker {\nprivate final Map<String, SafePoint> locations;\nprivate final Map<String, SafePoint> unmodifiableMap;\n\npublic PublishingVehicleTracker(Map<String, SafePoint> locations) {\nthis.locations = new ConcurrentHashMap<>(locations);\nthis.unmodifiableMap = Collections.unmodifiableMap(this.locations);\n}\n\npublic Map<String, SafePoint> getLocations() {\nreturn unmodifiableMap;\n}\n\npublic SafePoint getLocation(String id) {\nreturn locations.get(id);\n}\n\npublic void setLocation(String id, int x, int y) {\nif (!locations.containsKey(id))\nthrow new IllegalArgumentException(\"invalid vehicle name: \" + id);\nlocations.get(id).set(x, y);\n}\n\npublic static void main(String[] args) throws InterruptedException {\nMap<String, SafePoint> initialPoints = new HashMap<>();\ninitialPoints.put(\"V1\", new SafePoint(0, 0));\ninitialPoints.put(\"V2\", new SafePoint(10, 10));\ninitialPoints.put(\"V3\", new SafePoint(20, 20));\n\nPublishingVehicleTracker tracker = new PublishingVehicleTracker(initialPoints);\n\nThread[] threads = new Thread[2]; // fewer threads for faster JPF testing\n\nfor (int i = 0; i < 2; i++) {\nfinal int taskId = i;\nthreads[i] = new Thread(() -> {\nRandom rand = new Random();\nfor (int j = 0; j < 3; j++) { // fewer iterations\nString vehicleId = \"V\" + ((taskId % 3) + 1);\nint newX = rand.nextInt(6); // 0 to 5\nint newY = rand.nextInt(6); // 0 to 5\ntracker.setLocation(vehicleId, newX, newY);\nSystem.out.println(Thread.currentThread().getName() +\n\" updated \" + vehicleId + \" to (\" + newX + \", \" + newY + \")\");\ntry {\nThread.sleep(20); // shorter sleep\n} catch (InterruptedException e) {\nThread.currentThread().interrupt();\n}\n}\n});\n}\n\nfor (Thread t : threads) {\nt.start();\n}\n\nfor (Thread t : threads) {\nt.join();\n}\n\nSystem.out.println(\"\\nFinal vehicle locations:\");\ntracker.getLocations().forEach((id, point) ->\nSystem.out.println(id + \": (\" + point.getX() + \", \" + point.getY() + \")\"));\n}\n}\n\nclass SafePoint {\nprivate int x, y;\n\npublic SafePoint(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n\npublic SafePoint(SafePoint point) {\nthis(point.getX(), point.getY());\n}\n\npublic synchronized int getX() {\nreturn x;\n}\n\npublic synchronized int getY() {\nreturn y;\n}\n\npublic synchronized void set(int x, int y) {\nthis.x = x;\nthis.y = y;\n}\n}",
        "max_depth": "93",
        "jpf_details": [
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.09%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.41%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.43%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=110938,visited=151146,backtracked=261154,end=0\nsearch:             maxDepth=930,constraints=28362\nchoice generators:  thread=87962 (signal=0,lock=6758,sharedRef=73842,threadApi=2419,reschedule=13), data=0\nheap:               new=1160318,released=128573,maxLive=859,gcCycles=239817\ninstructions:       32936089\nmax memory:         1019MB\nloaded code:        classes=157,methods=2690\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.45%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=119823,visited=169489,backtracked=288410,end=0\nsearch:             maxDepth=930,constraints=28333\nchoice generators:  thread=97037 (signal=0,lock=7662,sharedRef=81769,threadApi=2791,reschedule=28), data=0\nheap:               new=153692,released=1431466,maxLive=856,gcCycles=264075\ninstructions:       31775325\nmax memory:         1019MB\nloaded code:        classes=152,methods=2643\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 66.43%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 66.43%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=194507,visited=84441,backtracked=278070,end=0\nsearch:             maxDepth=930,constraints=116814\nchoice generators:  thread=93596 (signal=0,lock=2593,sharedRef=66189,threadApi=807,reschedule=32), data=0\nheap:               new=55163,released=404637,maxLive=825,gcCycles=270038\ninstructions:       18065630\nmax memory:         1020MB\nloaded code:        classes=147,methods=2604\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "no errors detected"
        ],
        "codebleu_score": [
            56.72,
            54.49,
            57.35
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 1.0
    },
    {
        "prompt_title": "Waiting for results to be calculated in parallel. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Write Java code that transforms sequential execution into parallel execution using an Executor. The code should include two main processing methods: one that processes a list of elements sequentially by iterating and processing each element in turn, and another that submits each element for parallel processing via an executor. Additionally, implement recursive versions of both sequential and parallel processing methods that traverse a tree structure of nodes, computing results and collecting them in a thread-safe manner. The parallel version should properly utilize an ExecutorService to execute tasks concurrently, ensure all tasks complete before returning the final result collection, and use appropriate concurrency utilities for thread safety. Define interfaces Element and Node, where Node supports computation and retrieval of child nodes. Ensure the design follows good abstraction principles and includes proper generic typing. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary.\nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 3. Use a fixed thread pool or manually manage at most 2 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\n\ninterface Element {\n    String getId();\n    void process();\n}\n\ninterface Node {\n    String compute();\n    List<Node> getChildren();\n}\n\nclass SimpleElement implements Element {\n    private final String id;\n    \n    public SimpleElement(String id) {\n        this.id = id;\n    }\n    \n    @Override\n    public String getId() {\n        return id;\n    }\n    \n    @Override\n    public void process() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass TreeNode implements Node {\n    private final String value;\n    private final List<Node> children;\n    \n    public TreeNode(String value, List<Node> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    @Override\n    public String compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<Node> getChildren() {\n        return children;\n    }\n}\n\nclass Processor {\n    private final ExecutorService executor;\n    \n    public Processor() {\n        this.executor = Executors.newFixedThreadPool(1);\n    }\n    \n    public void processSequential(List<Element> elements) {\n        for (Element element : elements) {\n            element.process();\n        }\n    }\n    \n    public void processParallel(List<Element> elements) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Element element : elements) {\n            futures.add(executor.submit(() -> element.process()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public List<String> processTreeSequential(Node root) {\n        List<String> results = new ArrayList<>();\n        processNodeSequential(root, results);\n        return results;\n    }\n    \n    private void processNodeSequential(Node node, List<String> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (Node child : node.getChildren()) {\n            processNodeSequential(child, results);\n        }\n    }\n    \n    public List<String> processTreeParallel(Node root) {\n        ConcurrentLinkedQueue<String> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = processNodeParallel(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private CountDownLatch processNodeParallel(Node node, ConcurrentLinkedQueue<String> results) {\n        if (node == null) return new CountDownLatch(0);\n        \n        List<Node> children = node.getChildren();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            results.add(node.compute());\n            latch.countDown();\n        });\n        \n        for (Node child : children) {\n            executor.submit(() -> {\n                processNodeParallelHelper(child, results);\n                latch.countDown();\n            });\n        }\n        \n        return latch;\n    }\n    \n    private void processNodeParallelHelper(Node node, ConcurrentLinkedQueue<String> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (Node child : node.getChildren()) {\n            processNodeParallelHelper(child, results);\n        }\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProgram {\n    public static void main(String[] args) {\n        Processor processor = new Processor();\n        \n        List<Element> elements = Arrays.asList(\n            new SimpleElement(\"1\"),\n            new SimpleElement(\"2\"),\n            new SimpleElement(\"3\")\n        );\n        \n        long start = System.currentTimeMillis();\n        processor.processSequential(elements);\n        System.out.println(\"Sequential processing time: \" + (System.currentTimeMillis() - start) + \"ms\");\n        \n        start = System.currentTimeMillis();\n        processor.processParallel(elements);\n        System.out.println(\"Parallel processing time: \" + (System.currentTimeMillis() - start) + \"ms\");\n        \n        Node root = new TreeNode(\"root\", Arrays.asList(\n            new TreeNode(\"child1\", Arrays.asList(\n                new TreeNode(\"grandchild1\", Collections.emptyList()),\n                new TreeNode(\"grandchild2\", Collections.emptyList())\n            )),\n            new TreeNode(\"child2\", Arrays.asList(\n                new TreeNode(\"grandchild3\", Collections.emptyList())\n            ))\n        ));\n        \n        start = System.currentTimeMillis();\n        List<String> seqResults = processor.processTreeSequential(root);\n        System.out.println(\"Sequential tree results: \" + seqResults);\n        System.out.println(\"Sequential tree processing time: \" + (System.currentTimeMillis() - start) + \"ms\");\n        \n        start = System.currentTimeMillis();\n        List<String> parResults = processor.processTreeParallel(root);\n        System.out.println(\"Parallel tree results: \" + parResults);\n        System.out.println(\"Parallel tree processing time: \" + (System.currentTimeMillis() - start) + \"ms\");\n        \n        processor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\ninterface Element {\n    String getId();\n    void process();\n}\n\ninterface Node {\n    String compute();\n    List<Node> getChildren();\n}\n\nclass SimpleElement implements Element {\n    private final String id;\n    \n    public SimpleElement(String id) {\n        this.id = id;\n    }\n    \n    @Override\n    public String getId() {\n        return id;\n    }\n    \n    @Override\n    public void process() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass TreeNode implements Node {\n    private final String value;\n    private final List<Node> children;\n    \n    public TreeNode(String value, List<Node> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    @Override\n    public String compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<Node> getChildren() {\n        return children;\n    }\n}\n\nclass ProcessorService {\n    private final ExecutorService executor;\n    \n    public ProcessorService() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processSequential(List<Element> elements) {\n        for (Element element : elements) {\n            element.process();\n        }\n    }\n    \n    public void processParallel(List<Element> elements) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Element element : elements) {\n            futures.add(executor.submit(() -> element.process()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public List<String> processTreeSequential(Node root) {\n        List<String> results = new ArrayList<>();\n        processNodeSequential(root, results);\n        return results;\n    }\n    \n    private void processNodeSequential(Node node, List<String> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (Node child : node.getChildren()) {\n            processNodeSequential(child, results);\n        }\n    }\n    \n    public List<String> processTreeParallel(Node root) {\n        ConcurrentLinkedQueue<String> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = processNodeParallel(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private CountDownLatch processNodeParallel(Node node, ConcurrentLinkedQueue<String> results) {\n        if (node == null) return new CountDownLatch(0);\n        \n        List<Node> children = node.getChildren();\n        CountDownLatch latch = new CountDownLatch(1 + children.size());\n        \n        executor.submit(() -> {\n            results.add(node.compute());\n            latch.countDown();\n        });\n        \n        for (Node child : children) {\n            executor.submit(() -> {\n                processNodeParallelRecursive(child, results);\n                latch.countDown();\n            });\n        }\n        \n        return latch;\n    }\n    \n    private void processNodeParallelRecursive(Node node, ConcurrentLinkedQueue<String> results) {\n        if (node == null) return;\n        results.add(node.compute());\n        for (Node child : node.getChildren()) {\n            processNodeParallelRecursive(child, results);\n        }\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProcessor {\n    public static void main(String[] args) {\n        ProcessorService processor = new ProcessorService();\n        \n        List<Element> elements = Arrays.asList(\n            new SimpleElement(\"E1\"),\n            new SimpleElement(\"E2\"),\n            new SimpleElement(\"E3\"),\n            new SimpleElement(\"E4\")\n        );\n        \n        long startTime = System.currentTimeMillis();\n        processor.processSequential(elements);\n        long sequentialTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Sequential processing time: \" + sequentialTime + \"ms\");\n        \n        startTime = System.currentTimeMillis();\n        processor.processParallel(elements);\n        long parallelTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Parallel processing time: \" + parallelTime + \"ms\");\n        \n        Node root = new TreeNode(\"root\", Arrays.asList(\n            new TreeNode(\"child1\", Arrays.asList(\n                new TreeNode(\"grandchild1\", Collections.emptyList()),\n                new TreeNode(\"grandchild2\", Collections.emptyList())\n            )),\n            new TreeNode(\"child2\", Arrays.asList(\n                new TreeNode(\"grandchild3\", Collections.emptyList())\n            ))\n        ));\n        \n        startTime = System.currentTimeMillis();\n        List<String> sequentialResults = processor.processTreeSequential(root);\n        long treeSequentialTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Tree sequential results: \" + sequentialResults);\n        System.out.println(\"Tree sequential time: \" + treeSequentialTime + \"ms\");\n        \n        startTime = System.currentTimeMillis();\n        List<String> parallelResults = processor.processTreeParallel(root);\n        long treeParallelTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Tree parallel results: \" + parallelResults);\n        System.out.println(\"Tree parallel time: \" + treeParallelTime + \"ms\");\n        \n        processor.shutdown();\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\n\ninterface Element {\n    String getId();\n    void process();\n}\n\ninterface Node {\n    String compute();\n    List<Node> getChildren();\n}\n\nclass SimpleElement implements Element {\n    private final String id;\n    \n    public SimpleElement(String id) {\n        this.id = id;\n    }\n    \n    @Override\n    public String getId() {\n        return id;\n    }\n    \n    @Override\n    public void process() {\n        try {\n            Thread.sleep(100);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\nclass TreeNode implements Node {\n    private final String value;\n    private final List<Node> children;\n    \n    public TreeNode(String value, List<Node> children) {\n        this.value = value;\n        this.children = children;\n    }\n    \n    @Override\n    public String compute() {\n        try {\n            Thread.sleep(50);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return value;\n    }\n    \n    @Override\n    public List<Node> getChildren() {\n        return children;\n    }\n}\n\nclass ProcessingService {\n    private final ExecutorService executor;\n    \n    public ProcessingService() {\n        this.executor = Executors.newFixedThreadPool(2);\n    }\n    \n    public void processSequential(List<Element> elements) {\n        for (Element element : elements) {\n            element.process();\n        }\n    }\n    \n    public void processParallel(List<Element> elements) {\n        List<Future<?>> futures = new ArrayList<>();\n        for (Element element : elements) {\n            futures.add(executor.submit(() -> element.process()));\n        }\n        for (Future<?> future : futures) {\n            try {\n                future.get();\n            } catch (InterruptedException | ExecutionException e) {\n                Thread.currentThread().interrupt();\n            }\n        }\n    }\n    \n    public List<String> processTreeSequential(Node root) {\n        List<String> results = new ArrayList<>();\n        processNodeSequential(root, results);\n        return results;\n    }\n    \n    private void processNodeSequential(Node node, List<String> results) {\n        if (node == null) {\n            return;\n        }\n        results.add(node.compute());\n        for (Node child : node.getChildren()) {\n            processNodeSequential(child, results);\n        }\n    }\n    \n    public List<String> processTreeParallel(Node root) {\n        ConcurrentLinkedQueue<String> results = new ConcurrentLinkedQueue<>();\n        CountDownLatch latch = processNodeParallel(root, results);\n        try {\n            latch.await();\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n        return new ArrayList<>(results);\n    }\n    \n    private CountDownLatch processNodeParallel(Node node, ConcurrentLinkedQueue<String> results) {\n        if (node == null) {\n            return new CountDownLatch(0);\n        }\n        \n        List<Node> children = node.getChildren();\n        CountDownLatch latch = new CountDownLatch(children.size() + 1);\n        \n        executor.submit(() -> {\n            results.add(node.compute());\n            latch.countDown();\n        });\n        \n        for (Node child : children) {\n            executor.submit(() -> {\n                CountDownLatch childLatch = processNodeParallel(child, results);\n                try {\n                    childLatch.await();\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n                latch.countDown();\n            });\n        }\n        \n        return latch;\n    }\n    \n    public void shutdown() {\n        executor.shutdown();\n        try {\n            if (!executor.awaitTermination(10, TimeUnit.SECONDS)) {\n                executor.shutdownNow();\n            }\n        } catch (InterruptedException e) {\n            executor.shutdownNow();\n            Thread.currentThread().interrupt();\n        }\n    }\n}\n\npublic class ConcurrentProcessor {\n    public static void main(String[] args) {\n        ProcessingService service = new ProcessingService();\n        \n        List<Element> elements = Arrays.asList(\n            new SimpleElement(\"E1\"),\n            new SimpleElement(\"E2\"),\n            new SimpleElement(\"E3\"),\n            new SimpleElement(\"E4\")\n        );\n        \n        long startTime = System.currentTimeMillis();\n        service.processSequential(elements);\n        long sequentialTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Sequential processing time: \" + sequentialTime + \"ms\");\n        \n        startTime = System.currentTimeMillis();\n        service.processParallel(elements);\n        long parallelTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Parallel processing time: \" + parallelTime + \"ms\");\n        \n        Node root = new TreeNode(\"Root\", Arrays.asList(\n            new TreeNode(\"Child1\", Arrays.asList(\n                new TreeNode(\"GrandChild1\", Collections.emptyList()),\n                new TreeNode(\"GrandChild2\", Collections.emptyList())\n            )),\n            new TreeNode(\"Child2\", Arrays.asList(\n                new TreeNode(\"GrandChild3\", Collections.emptyList())\n            ))\n        ));\n        \n        startTime = System.currentTimeMillis();\n        List<String> seqResults = service.processTreeSequential(root);\n        long treeSeqTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Tree sequential results: \" + seqResults);\n        System.out.println(\"Tree sequential time: \" + treeSeqTime + \"ms\");\n        \n        startTime = System.currentTimeMillis();\n        List<String> parResults = service.processTreeParallel(root);\n        long treeParTime = System.currentTimeMillis() - startTime;\n        System.out.println(\"Tree parallel results: \" + parResults);\n        System.out.println(\"Tree parallel time: \" + treeParTime + \"ms\");\n        \n        service.shutdown();\n    }\n}"
        ],
        "graded_list": [
            true,
            true,
            false
        ],
        "ground_truth": "import java.util.*;\nimport java.util.concurrent.*;\n\npublic abstract class LLMC {\n\nvoid processSequentially(List<Element> elements) {\nfor (Element e : elements)\nprocess(e);\n}\n\nvoid processInParallel(Executor exec, List<Element> elements) {\nCountDownLatch latch = new CountDownLatch(elements.size());\nfor (final Element e : elements) {\nexec.execute(() -> {\nprocess(e);\nlatch.countDown();\n});\n}\ntry {\nlatch.await();\n} catch (InterruptedException ie) {\nThread.currentThread().interrupt();\n}\n}\n\npublic abstract void process(Element e);\n\npublic <T> void sequentialRecursive(List<Node<T>> nodes, Collection<T> results) {\nfor (Node<T> n : nodes) {\nresults.add(n.compute());\nsequentialRecursive(n.getChildren(), results);\n}\n}\n\npublic <T> Collection<T> parallelRecursive(List<Node<T>> nodes) throws InterruptedException {\nCollection<T> results = Collections.synchronizedList(new ArrayList<>());\nCountDownLatch latch = new CountDownLatch(nodes.size());\n\nThread worker = new Thread(() -> {\nfor (Node<T> n : nodes) {\nT result = n.compute();\nresults.add(result);\nsequentialRecursive(n.getChildren(), results);\nlatch.countDown();\n}\n});\n\nworker.start();\nlatch.await();\n\nreturn results;\n}\n\ninterface Element {}\ninterface Node<T> { T compute(); List<Node<T>> getChildren(); }\n\nstatic class MyElement implements Element {\nprivate final String name;\npublic MyElement(String name) { this.name = name; }\npublic String toString() { return \"Element: \" + name; }\n}\n\nstatic class MyNode implements Node<String> {\nprivate final String name;\nprivate final List<Node<String>> children;\npublic MyNode(String name, List<Node<String>> children) {\nthis.name = name;\nthis.children = children != null ? children : Collections.emptyList();\n}\npublic String compute() {\nreturn name;\n}\npublic List<Node<String>> getChildren() { return children; }\n}\n\npublic static void main(String[] args) throws InterruptedException {\nLLMC instance = new LLMC() {\npublic void process(Element e) {\n// Minimal processing\n}\n};\n\nList<Element> elements = Arrays.asList(new MyElement(\"A\"));\n\ninstance.processSequentially(elements);\n\nThread executor = new Thread(() -> {\ninstance.processInParallel(Runnable::run, elements);\n});\nexecutor.start();\nexecutor.join();\n\nNode<String> leaf = new MyNode(\"Leaf\", null);\nNode<String> root = new MyNode(\"Root\", Arrays.asList(leaf));\nList<Node<String>> tree = Arrays.asList(root);\n\nCollection<String> sequentialResults = new ArrayList<>();\ninstance.sequentialRecursive(tree, sequentialResults);\n\nCollection<String> parallelResults = instance.parallelRecursive(tree);\nSystem.out.println(parallelResults);\n}\n}",
        "max_depth": "5979",
        "jpf_details": [
            "Unique logical threads created during execution: 2\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 25.13%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 49.75%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=178073,visited=59750,backtracked=179256,end=59751\nsearch:             maxDepth=59790,constraints=3\nchoice generators:  thread=178070 (signal=0,lock=6,sharedRef=22,threadApi=7,reschedule=59751), data=0\nheap:               new=60750,released=4421739,maxLive=838,gcCycles=237823\ninstructions:       70791387\nmax memory:         1010MB\nloaded code:        classes=152,methods=2731\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 42.93%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 67.49%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 63.77%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=157495,visited=116495,backtracked=214858,end=2724\nsearch:             maxDepth=59790,constraints=31824\nchoice generators:  thread=140814 (signal=0,lock=7,sharedRef=109353,threadApi=17,reschedule=20152), data=0\nheap:               new=53929,released=736037,maxLive=852,gcCycles=273990\ninstructions:       42439768\nmax memory:         1015MB\nloaded code:        classes=152,methods=2731\n\n====================================================== search finished",
            "Unique logical threads created during execution: 3\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 1.38%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 8.28%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 48.97%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\"\n\n====================================================== statistics\nstates:             new=145,visited=0,backtracked=0,end=1\nsearch:             maxDepth=145,constraints=0\nchoice generators:  thread=145 (signal=0,lock=7,sharedRef=119,threadApi=12,reschedule=2), data=0\nheap:               new=954,released=95,maxLive=852,gcCycles=144\ninstructions:       19959\nmax memory:         981MB\nloaded code:        classes=147,methods=2698\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "no errors detected",
            "no errors detected",
            "error #1: gov.nasa.jpf.vm.NotDeadlockedProperty \"deadlock encountered:   thread java.lang.Thread:{i...\""
        ],
        "codebleu_score": [
            57.73,
            58.32,
            58.03
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 1.0,
        "pass@3": 0.6666666666666666
    },
    {
        "prompt_title": "Wrapping a Map with a read-write lock. M0",
        "prompt_content": "Please write a concurrent program in Java 8 that implements the following functionality: Create a Java class called ReadWriteMap that wraps a standard Map and provides thread-safe access using a read-write lock mechanism. The class should allow multiple readers or a single writer at any given time. Use ReentrantReadWriteLock from the java.util.concurrent.locks package to control access. For all write operations (put, remove, putAll, clear), acquire the write lock, and for all read operations (get, size, isEmpty, containsKey, containsValue), acquire the read lock. Ensure that locks are always released after each operation using try-finally blocks. The constructor should accept an existing Map instance to wrap. The requirements are as follows:\n\nAll classes and methods must be defined within a single .java file;\nThe program must include a public static void main(String[] args) method as the entry point;\nNo external libraries or dependencies should be used;\nThe code should be clear, well-structured, and follow Java 8 syntax standards;\nIf multiple classes are needed, they should all be placed in the same file, with non-public classes defined using the class keyword. \nThe implementation must use multithreading to perform tasks concurrently. You may use Thread, Runnable, or ExecutorService from the standard Java library to achieve this. Ensure that thread safety is considered where necessary. \nWrite Java 8 code only. Output a single complete code block using ```java```. Do not include any explanations, comments, or extra text. Only output the code, nothing else. \nThe total number of threads used in the program, including the main thread, must not exceed 4. Use a fixed thread pool or manually manage at most 3 additional threads beyond the main thread. Avoid unbounded thread creation or cached thread pools. \nDo not add any annotations. \nWhen generating the code, if it contains loops or random number generation, please minimize the loop iteration count (e.g., 2–3) and the random number range (e.g., 0–2).",
        "code_list": [
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass ReadWriteMap<K, V> {\n    private final Map<K, V> map;\n    private final ReadWriteLock lock = new ReentrantReadWriteLock();\n    private final Lock readLock = lock.readLock();\n    private final Lock writeLock = lock.writeLock();\n\n    public ReadWriteMap(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) {\n        Map<String, Integer> baseMap = new HashMap<>();\n        ReadWriteMap<String, Integer> rwMap = new ReadWriteMap<>(baseMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                rwMap.put(\"key\" + i, i);\n                System.out.println(\"Writer 1: put key\" + i + \" = \" + i);\n                try {\n                    Thread.sleep(50);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                Integer value = rwMap.get(\"key\" + i);\n                System.out.println(\"Reader 1: key\" + i + \" = \" + value);\n                try {\n                    Thread.sleep(30);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.submit(() -> {\n            for (int i = 0; i < 10; i++) {\n                boolean contains = rwMap.containsKey(\"key\" + i);\n                System.out.println(\"Reader 2: contains key\" + i + \" = \" + contains);\n                int size = rwMap.size();\n                System.out.println(\"Reader 2: size = \" + size);\n                try {\n                    Thread.sleep(40);\n                } catch (InterruptedException e) {\n                    Thread.currentThread().interrupt();\n                }\n            }\n        });\n\n        executor.shutdown();\n        try {\n            executor.awaitTermination(10, TimeUnit.SECONDS);\n        } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n        }\n    }\n}",
            "import java.util.*;\nimport java.util.concurrent.*;\nimport java.util.concurrent.locks.*;\n\nclass ReadWriteMap<K, V> {\n    private final Map<K, V> map;\n    private final ReentrantReadWriteLock lock = new ReentrantReadWriteLock();\n    private final ReentrantReadWriteLock.ReadLock readLock = lock.readLock();\n    private final ReentrantReadWriteLock.WriteLock writeLock = lock.writeLock();\n\n    public ReadWriteMap(Map<K, V> map) {\n        this.map = map;\n    }\n\n    public V get(K key) {\n        readLock.lock();\n        try {\n            return map.get(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public int size() {\n        readLock.lock();\n        try {\n            return map.size();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean isEmpty() {\n        readLock.lock();\n        try {\n            return map.isEmpty();\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsKey(K key) {\n        readLock.lock();\n        try {\n            return map.containsKey(key);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public boolean containsValue(V value) {\n        readLock.lock();\n        try {\n            return map.containsValue(value);\n        } finally {\n            readLock.unlock();\n        }\n    }\n\n    public V put(K key, V value) {\n        writeLock.lock();\n        try {\n            return map.put(key, value);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public V remove(K key) {\n        writeLock.lock();\n        try {\n            return map.remove(key);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void putAll(Map<? extends K, ? extends V> m) {\n        writeLock.lock();\n        try {\n            map.putAll(m);\n        } finally {\n            writeLock.unlock();\n        }\n    }\n\n    public void clear() {\n        writeLock.lock();\n        try {\n            map.clear();\n        } finally {\n            writeLock.unlock();\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws InterruptedException {\n        Map<String, Integer> baseMap = new HashMap<>();\n        ReadWriteMap<String, Integer> readWriteMap = new ReadWriteMap<>(baseMap);\n        ExecutorService executor = Executors.newFixedThreadPool(3);\n        CountDownLatch latch = new CountDownLatch(3);\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 10; i++) {\n                    readWriteMap.put(\"key\" + i, i);\n                    Thread.sleep(10);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                for (int i = 0; i < 20; i++) {\n                    Integer value = readWriteMap.get(\"key\" + (i % 10));\n                    System.out.println(\"Read: key\" + (i % 10) + \" = \" + value);\n                    Thread.sleep(5);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        });\n\n        executor.submit(() -> {\n            try {\n                Thread.sleep(50);\n                for (int i = 0; i < 5; i++) {\n                    readWriteMap.remove(\"key\" + i);\n                    System.out.println(\"Removed: key\" + i);\n                    Thread.sleep(15);\n                }\n            } catch (InterruptedException e) {\n                Thread.currentThread().interrupt();\n            } finally {\n                latch.countDown();\n            }\n        });\n\n        latch.await();\n        executor.shutdown();\n        executor.awaitTermination(1, TimeUnit.SECONDS);\n\n        System.out.println(\"Final map size: \" + readWriteMap.size());\n        System.out.println(\"Is empty: \" + readWriteMap.isEmpty());\n    }\n}",
            "import java.util.Map;\nimport java.util.HashMap;\nimport java.util.Collection;\nimport java.util.Set;\n\nclass ReadWriteMap<K, V> {\n  private final Map<K, V> map;\n  private final Object readLock = new Object();\n  private final Object writeLock = new Object();\n  private int readers = 0;\n  private boolean writer = false;\n\n  public ReadWriteMap(Map<K, V> map) {\n    this.map = map;\n  }\n\n  private void acquireReadLock() {\n    synchronized (readLock) {\n      while (writer) {\n        try {\n          readLock.wait();\n        } catch (InterruptedException e) {\n          Thread.currentThread().interrupt();\n          throw new RuntimeException(e);\n        }\n      }\n      readers++;\n    }\n  }\n\n  private void releaseReadLock() {\n    synchronized (readLock) {\n      readers--;\n      if (readers == 0) {\n        readLock.notifyAll();\n      }\n    }\n  }\n\n  private void acquireWriteLock() {\n    synchronized (writeLock) {\n      synchronized (readLock) {\n        while (readers > 0 || writer) {\n          try {\n            readLock.wait();\n          } catch (InterruptedException e) {\n            Thread.currentThread().interrupt();\n            throw new RuntimeException(e);\n          }\n        }\n        writer = true;\n      }\n    }\n  }\n\n  private void releaseWriteLock() {\n    synchronized (readLock) {\n      writer = false;\n      readLock.notifyAll();\n    }\n  }\n\n  public V get(Object key) {\n    acquireReadLock();\n    try {\n      return map.get(key);\n    } finally {\n      releaseReadLock();\n    }\n  }\n\n  public int size() {\n    acquireReadLock();\n    try {\n      return map.size();\n    } finally {\n      releaseReadLock();\n    }\n  }\n\n  public boolean isEmpty() {\n    acquireReadLock();\n    try {\n      return map.isEmpty();\n    } finally {\n      releaseReadLock();\n    }\n  }\n\n  public boolean containsKey(Object key) {\n    acquireReadLock();\n    try {\n      return map.containsKey(key);\n    } finally {\n      releaseReadLock();\n    }\n  }\n\n  public boolean containsValue(Object value) {\n    acquireReadLock();\n    try {\n      return map.containsValue(value);\n    } finally {\n      releaseReadLock();\n    }\n  }\n\n  public V put(K key, V value) {\n    acquireWriteLock();\n    try {\n      return map.put(key, value);\n    } finally {\n      releaseWriteLock();\n    }\n  }\n\n  public V remove(Object key) {\n    acquireWriteLock();\n    try {\n      return map.remove(key);\n    } finally {\n      releaseWriteLock();\n    }\n  }\n\n  public void putAll(Map<? extends K, ? extends V> m) {\n    acquireWriteLock();\n    try {\n      map.putAll(m);\n    } finally {\n      releaseWriteLock();\n    }\n  }\n\n  public void clear() {\n    acquireWriteLock();\n    try {\n      map.clear();\n    } finally {\n      releaseWriteLock();\n    }\n  }\n}\n\npublic class ReadWriteMapProgram {\n  public static void main(String[] args) {\n    Map<String, Integer> baseMap = new HashMap<>();\n    ReadWriteMap<String, Integer> safeMap = new ReadWriteMap<>(baseMap);\n\n    Thread writer1 = new Thread(() -> {\n      for (int i = 0; i < 100; i++) {\n        safeMap.put(\"key\" + i, i);\n        try {\n          Thread.sleep(1);\n        } catch (InterruptedException e) {\n          Thread.currentThread().interrupt();\n          break;\n        }\n      }\n      System.out.println(\"Writer thread 1 completed\");\n    });\n\n    Thread reader1 = new Thread(() -> {\n      try {\n        Thread.sleep(50);\n      } catch (InterruptedException e) {\n        Thread.currentThread().interrupt();\n        return;\n      }\n      for (int i = 0; i < 50; i++) {\n        Integer value = safeMap.get(\"key\" + i);\n        boolean contains = safeMap.containsKey(\"key\" + i);\n        int size = safeMap.size();\n        try {\n          Thread.sleep(2);\n        } catch (InterruptedException e) {\n          Thread.currentThread().interrupt();\n          break;\n        }\n      }\n      System.out.println(\"Reader thread 1 completed\");\n    });\n\n    Thread reader2 = new Thread(() -> {\n      try {\n        Thread.sleep(75);\n      } catch (InterruptedException e) {\n        Thread.currentThread().interrupt();\n        return;\n      }\n      for (int i = 50; i < 80; i++) {\n        Integer value = safeMap.get(\"key\" + i);\n        boolean isEmpty = safeMap.isEmpty();\n        boolean containsValue = safeMap.containsValue(i);\n        try {\n          Thread.sleep(3);\n        } catch (InterruptedException e) {\n          Thread.currentThread().interrupt();\n          break;\n        }\n      }\n      System.out.println(\"Reader thread 2 completed\");\n    });\n\n    writer1.start();\n    reader1.start();\n    reader2.start();\n\n    try {\n      writer1.join();\n      reader1.join();\n      reader2.join();\n    } catch (InterruptedException e) {\n      Thread.currentThread().interrupt();\n    }\n\n    System.out.println(\"Final map size: \" + safeMap.size());\n    System.out.println(\"Map contains key50: \" + safeMap.containsKey(\"key50\"));\n    System.out.println(\"Map is empty: \" + safeMap.isEmpty());\n  }\n}"
        ],
        "graded_list": [
            false,
            false,
            true
        ],
        "ground_truth": "import java.util.HashMap;\nimport java.util.Map;\n\npublic class SimpleReadWriteMap<K, V> {\nprivate final Map<K, V> map = new HashMap<>();\n\npublic synchronized V put(K key, V value) {\nreturn map.put(key, value);\n}\n\npublic synchronized V get(Object key) {\nreturn map.get(key);\n}\n\npublic synchronized int size() {\nreturn map.size();\n}\n\npublic static void main(String[] args) throws InterruptedException {\nfinal SimpleReadWriteMap<String, String> rwMap = new SimpleReadWriteMap<>();\n\nThread writer = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nrwMap.put(\"key\" + i, \"value\" + i);\nSystem.out.println(\"Writer wrote: key\" + i);\n}\n}\n});\n\nThread reader1 = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nString val = rwMap.get(\"key\" + i);\nif (val != null) {\nSystem.out.println(\"Reader1 read: \" + val);\n}\n}\n}\n});\n\nThread reader2 = new Thread(new Runnable() {\npublic void run() {\nfor (int i = 0; i < 3; i++) {\nString val = rwMap.get(\"key\" + i);\nif (val != null) {\nSystem.out.println(\"Reader2 read: \" + val);\n}\n}\n}\n});\n\nwriter.start();\nreader1.start();\nreader2.start();\n\nwriter.join();\nreader1.join();\nreader2.join();\n\nSystem.out.println(\"Final size: \" + rwMap.size());\n}\n}",
        "max_depth": "98",
        "jpf_details": [
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=494,released=0,maxLive=0,gcCycles=0\ninstructions:       6422\nmax memory:         981MB\nloaded code:        classes=90,methods=1745\n\n====================================================== search finished",
            "Unique logical threads created during execution: 1\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n\n====================================================== results\nerror #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"\n\n====================================================== statistics\nstates:             new=1,visited=0,backtracked=0,end=0\nsearch:             maxDepth=1,constraints=0\nchoice generators:  thread=1 (signal=0,lock=1,sharedRef=0,threadApi=0,reschedule=0), data=0\nheap:               new=494,released=0,maxLive=0,gcCycles=0\ninstructions:       6422\nmax memory:         981MB\nloaded code:        classes=90,methods=1745\n\n====================================================== search finished",
            "Unique logical threads created during execution: 4\n[JPF-STARVATION] search end，start concluding starvation...\n[JPF-STARVATION] Thread ID: 0 OK (waiting proportion: 0.00%)\n[JPF-STARVATION] Thread ID: 1 OK (waiting proportion: 52.08%)\n[JPF-STARVATION] Thread ID: 2 OK (waiting proportion: 55.88%)\n[JPF-STARVATION] Thread ID: 3 OK (waiting proportion: 57.32%)\n\n====================================================== results\nno errors detected\n\n====================================================== statistics\nstates:             new=123073,visited=169942,backtracked=292037,end=0\nsearch:             maxDepth=980,constraints=17047\nchoice generators:  thread=114908 (signal=5746,lock=28938,sharedRef=59942,threadApi=4480,reschedule=15802), data=0\nheap:               new=114197,released=78892,maxLive=965,gcCycles=286102\ninstructions:       3777186\nmax memory:         1018MB\nloaded code:        classes=87,methods=1859\n\n====================================================== search finished"
        ],
        "jpf_result": [
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"",
            "error #1: gov.nasa.jpf.vm.NoUncaughtExceptionsProperty \"java.lang.Error: java.lang.NoSuchFieldException: t...\"",
            "no errors detected"
        ],
        "codebleu_score": [
            58.32,
            58.58,
            61.89
        ],
        "llm_output": [
            "",
            "",
            ""
        ],
        "pass@1": 0.0,
        "pass@3": 0.3333333333333333
    }
]