我正在开发一些应用程序并使用ThreadPoolExecutor来处理各种任务。一段时间后，ThreadPoolExecutor陷入困境。为了在更简单的环境中模拟这个，我编写了一个简单的代码，我可以模拟这个问题。
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.RejectedExecutionHandler;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
public class MyThreadPoolExecutor {
private int poolSize = 10;
private int maxPoolSize = 50;
private long keepAliveTime = 10;
private ThreadPoolExecutor threadPool = null;
private final ArrayBlockingQueue<Runnable> queue = new ArrayBlockingQueue<Runnable>(
100000);
public MyThreadPoolExecutor() {
threadPool = new ThreadPoolExecutor(poolSize, maxPoolSize,
keepAliveTime, TimeUnit.SECONDS, queue);
threadPool.setRejectedExecutionHandler(new RejectedExecutionHandler() {
@Override
public void rejectedExecution(Runnable runnable,
ThreadPoolExecutor threadPoolExecutor) {
System.out
.println("Execution rejected. Please try restarting the application.");
}
});
}
public void runTask(Runnable task) {
threadPool.execute(task);
}
public void shutDown() {
threadPool.shutdownNow();
}
public ThreadPoolExecutor getThreadPool() {
return threadPool;
}
public void setThreadPool(ThreadPoolExecutor threadPool) {
this.threadPool = threadPool;
}
public static void main(String[] args) {
MyThreadPoolExecutor mtpe = new MyThreadPoolExecutor();
for (int i = 0; i < 1000; i++) {
final int j = i;
mtpe.runTask(new Runnable() {
@Override
public void run() {
System.out.println(j);
}
});
}
}
}
尝试执行此代码几次。它通常打印出控制台上的数字，当所有线程结束时，它就存在。但有时，它完成了所有任务，然后没有被终止。线程转储如下：
MyThreadPoolExecutor [Java Application]
MyThreadPoolExecutor at localhost:2619 (Suspended)
Daemon System Thread [Attach Listener] (Suspended)
Daemon System Thread [Signal Dispatcher] (Suspended)
Daemon System Thread [Finalizer] (Suspended)
Object.wait(long) line: not available [native method]
ReferenceQueue<T>.remove(long) line: not available
ReferenceQueue<T>.remove() line: not available
Finalizer$FinalizerThread.run() line: not available
Daemon System Thread [Reference Handler] (Suspended)
Object.wait(long) line: not available [native method]
Reference$Lock(Object).wait() line: 485
Reference$ReferenceHandler.run() line: not available
Thread [pool-1-thread-1] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-2] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-3] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-4] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-6] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-8] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-5] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-10] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-9] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [pool-1-thread-7] (Suspended)
Unsafe.park(boolean, long) line: not available [native method]
LockSupport.park(Object) line: not available
AbstractQueuedSynchronizer$ConditionObject.await() line: not available
ArrayBlockingQueue<E>.take() line: not available
ThreadPoolExecutor.getTask() line: not available
ThreadPoolExecutor$Worker.run() line: not available
Thread.run() line: not available
Thread [DestroyJavaVM] (Suspended)
C:\Program Files\Java\jre1.6.0_07\bin\javaw.exe (Jun 17, 2010 10:42:33 AM)
在我的实际应用程序中，ThreadPoolExecutor线程进入此状态然后它停止响应。
此致 Ravi Rao
答案 0 :(得分：9)