如何在Java中杀死Java .lang. thread ?


当前回答

请参阅Sun的这篇文章,了解他们为什么弃用thread .stop()。它将详细说明为什么这是一个糟糕的方法,以及应该做些什么来安全地停止线程。

他们推荐的方法是使用一个共享变量作为标志,要求后台线程停止。这个变量可以由请求线程终止的另一个对象设置。

其他回答

我想根据所积累的意见补充几点看法。

Thread.stop() will stop a thread if the security manager allows it. Thread.stop() is dangerous. Having said that, if you are working in a JEE environment and you have no control over the code being called, it may be necessary; see Why is Thread.stop deprecated? You should never stop stop a container worker thread. If you want to run code that tends to hang, (carefully) start a new daemon thread and monitor it, killing if necessary. stop() creates a new ThreadDeathError error on the calling thread and then throws that error on the target thread. Therefore, the stack trace is generally worthless. In JRE 6, stop() checks with the security manager and then calls stop1() that calls stop0(). stop0() is native code. As of Java 13 Thread.stop() has not been removed (yet), but Thread.stop(Throwable) was removed in Java 11. (mailing list, JDK-8204243)

“杀死一个线程”不是一个正确的短语。这里有一种方法我们可以在will上实现线程的优雅完成/退出:

我使用的Runnable:

class TaskThread implements Runnable {

    boolean shouldStop;

    public TaskThread(boolean shouldStop) {
        this.shouldStop = shouldStop;
    }

    @Override
    public void run() {

        System.out.println("Thread has started");

        while (!shouldStop) {
            // do something
        }

        System.out.println("Thread has ended");

    }

    public void stop() {
        shouldStop = true;
    }

}

触发类:

public class ThreadStop {

    public static void main(String[] args) {

        System.out.println("Start");

        // Start the thread
        TaskThread task = new TaskThread(false);
        Thread t = new Thread(task);
        t.start();

        // Stop the thread
        task.stop();

        System.out.println("End");

    }

}

没有办法优雅地终止线程。

您可以尝试中断线程,一个常用的策略是使用毒丸来通知线程停止自己

public class CancelSupport {
    public static class CommandExecutor implements Runnable {
            private BlockingQueue<String> queue;
            public static final String POISON_PILL  = “stopnow”;
            public CommandExecutor(BlockingQueue<String> queue) {
                    this.queue=queue;
            }
            @Override
            public void run() {
                    boolean stop=false;
                    while(!stop) {
                            try {
                                    String command=queue.take();
                                    if(POISON_PILL.equals(command)) {
                                            stop=true;
                                    } else {
                                            // do command
                                            System.out.println(command);
                                    }
                            } catch (InterruptedException e) {
                                    stop=true;
                            }
                    }
                    System.out.println(“Stopping execution”);
            }

    }

}

BlockingQueue<String> queue=new LinkedBlockingQueue<String>();
Thread t=new Thread(new CommandExecutor(queue));
queue.put(“hello”);
queue.put(“world”);
t.start();
Thread.sleep(1000);
queue.put(“stopnow”);

http://anandsekar.github.io/cancel-support-for-threads/

你有办法做到这一点。但如果你不得不使用它,要么你是一个糟糕的程序员,要么你使用的是一个糟糕的程序员编写的代码。所以,你应该考虑停止成为一个糟糕的程序员或停止使用这些糟糕的代码。 这种解决方案只适用于别无选择的情况。

Thread f = <A thread to be stopped>
Method m = Thread.class.getDeclaredMethod( "stop0" , new Class[]{Object.class} );
m.setAccessible( true );
m.invoke( f , new ThreadDeath() );

我没有得到中断工作在Android,所以我用这个方法,工作完美:

boolean shouldCheckUpdates = true;

private void startupCheckForUpdatesEveryFewSeconds() {
    Thread t = new Thread(new CheckUpdates());
    t.start();
}

private class CheckUpdates implements Runnable{
    public void run() {
        while (shouldCheckUpdates){
            //Thread sleep 3 seconds
            System.out.println("Do your thing here");
        }
    }
}

 public void stop(){
        shouldCheckUpdates = false;
 }