清除 Thread.interrupt() 标志的方法

我最近继承了一个大型Java应用程序，其中几乎没有线程安全性。我目前正在研究的是让所有线程正确处理被中断的情况，而不是使用非常糟糕的线程Thread.stop().

部分问题是我不知道清除中断标志的每个方法调用。

目前我知道以下内容将清除中断标志：

Thread.interrupted()
Thread.sleep(long)
Thread.join()
Thread.join(long)
Object.wait()
Object.wait(long)

我还缺少什么？谢谢

部分问题是我不知道清除中断标志的每个方法调用。

需要澄清的是，以下方法只需调用它们即可清除中断标志：

Thread.interrupted()
Thread.isInterrupted(true) -- added to your list

为此原因Thread.currentThread().isInterrupted()应始终使用。

以下方法将清除中断标志立即地投掷InterruptedException或者如果它们被调用然后线程被中断or如果线程是already被中断，然后它们被调用（参见下面的 junit 代码）。所以不是清除标志的方法，而是抛出异常。

您的初始清单：

Thread.interrupted()
Thread.sleep(long)
Thread.join()
Thread.join(long)
Object.wait()
Object.wait(long)

添加到您的列表：

Thread.sleep(long, int)
Thread.join(int, long)
Thread.isInterrupted(true)
Object.wait(int, long)
BlockingQueue.put(...)
BlockingQueue.offer(...)
BlockingQueue.take(...)
BlockingQueue.poll(...)
Future.get(...)
Process.waitFor()
ExecutorService.invokeAll(...)
ExecutorService.invokeAny(...)
ExecutorService.awaitTermination(...)
CompletionService.poll(...)
CompletionService.take(...)
CountDownLatch.await(...)
CyclicBarrier.await(...)
Semaphore.acquire(...)
Semaphore.tryAcquire(...)
Lock.lockInteruptibly()
Lock.tryLock(...)

请注意正确的模式与any捕获的代码InterruptedException就是立即重新中断线程。我们这样做是为了防止其他人依赖thread.isInterrupted() method:

try {
    ...
} catch (InterruptedException e) {
    // immediately re-interrupt the thread
    Thread.currentThread().interrupt();
    // log the exception or [likely] quit the thread
}

JUnit 代码演示了其中一些内容：

assertFalse(Thread.currentThread().isInterrupted());
// you can do this from another thread by saying: someThread.interrupt();
Thread.currentThread().interrupt();
// this method does _not_ clear the interrupt flag
assertTrue(Thread.currentThread().isInterrupted());
// but this one _does_ and should probably not be used
assertTrue(Thread.interrupted());
assertFalse(Thread.currentThread().isInterrupted());
Thread.currentThread().interrupt();
assertTrue(Thread.currentThread().isInterrupted());
try {
    // this throws immediately because the thread is _already_ interrupted
    Thread.sleep(1);
    fail("will never get here");
} catch (InterruptedException e) {
    // and when the InterruptedException is throw, it clears the interrupt
    assertFalse(Thread.currentThread().isInterrupted());
    // we should re-interrupt the thread so other code can use interrupt status
    Thread.currentThread().interrupt();
}
assertTrue(Thread.currentThread().isInterrupted());