Question

我的结构是这样的：
锁定包装器 - 用于存储锁定，条件和响应中的对象

public class LockWrapper{
    private Lock lock;
    private Condition myCondition;
    private MyObject myObject;

    public LockWrapper(Lock lock, Condition myCondition) {
        this.lock = lock;
        this.myCondition = myCondition;
    }

    public Condition getMyCondition() {
        return myCondition;
    }

    public MyObject getMyObject() {
        return myObject;
    }

    public void setObject(MyObject myObject) {
        this.myObject = myObject;
    }

    public Lock getLock() {
        return lock;
    }

}

任务 - 推入线程池执行。它启动对服务器的请求，然后等待服务器响应。

public class MyTask implements Runnable{
    private Lock lock = new ReentrantLock();
    private Condition myCondition = lock.newCondition();
    private MyWebSocketAPI api;

    public MyTask(MyWebSocketAPI api) {
         this.api = api;
    }

    @Override
    public void run() {
         lock.lock();
         try {
              // long randomLong = generateRandomLong();
              api.sendRequest(randomLong, new LockWrapper(lock, myCondition));
              myCondition.await();
              //do something after we got a response
         } finally{
              lock.unlock();
         }
    }

}

WebSocket - 获取请求并通知任务有关响应

 public abstract class MyWebSocketAPI extends WebSocketClient {
    //...
    private Map<Long, LockWrapper> lockWrappers = new ConcurrentHashMap<>();

    public void sendRequest(Long id, LockWrapper lockWrapper){
        this.lockWrappers.put(id, lockWrapper);
        //processRequest
    }

    @Override
    public void onMessage(String message) {
        LockWrapper lockWrapper = lockWrappers.get(message.get(0).getAsLong());

        lockWrapper.getLock().lock();
        try{
            lockWrapper.setMyObject(new MyObject(message));
            this.lockWrappers.put(message.get(0).getAsLong(), lockWrapper);
            lockWrapper.getMyCondition().signalAll();
        } finally {
            lockWrapper.getLock().unlock();
        }
    }

    //...
 }

行lockWrapper.getMyCondition().signalAll();抛出异常：

java.lang.IllegalMonitorStateException: null
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.signalAll(AbstractQueuedSynchronizer.java:1954)

当我尝试通知我们获取对象的任务时，为什么我的条件会抛出此异常？我在某个地方犯了错误，或者Java不允许共享条件吗？

Answer 1

这是Task中的错误。问题是我在方法运行中创建了全局和本地的锁定和条件。锁和条件具有相同的名称。在某些情况下，我使用lock，在某些情况下this.lock（但它是两个不同的锁）。结果，在方法onMessage中，我有条件和锁定没有连接在一起。删除重复项后，一切正常。

类之间的Java共享条件抛出IllegalMonitorStateException：null

1 个答案: