立即停止线程

Question

public class A() {
    public void methodA() {
        For (int n=0;n<100;n++) {
        //Do something recursive
        }
        //Another for-loop here

        //A resursive method here

        //Another for-loop here

        finishingMethod();        
    }    
}

public class B() {
    public void runEverything() {
        Runnable runnable = new Runnable() {
            @Override
            public void run() {
                try {
                    Thread.sleep(1000);
                    A a = new A();
                    a.methodA();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        };
       Thread thread = new Thread(runnable);
       thread.start();
    }

Answer 1

thread.Interrupt不会停止线程（除非它处于睡眠状态，在这种情况下将抛出InterruptedException)。中断基本上是向线程发送一条消息，指示它已被中断，但它不会导致线程立即停止。

当您有长时间的循环操作时，使用一个标志来检查线程是否已被取消是一种标准的方法。您的methodA可以修改以添加该标志，因此可以执行如下操作：

// this is a new instance variable in `A`
private volatile boolean cancelled = false;

// this is part of your methodA
for (int n=0;n<100;n++) {
  if ( cancelled ) {
    return; // or handle this however you want
  }    
}

// each of your other loops should work the same way

则可以添加cancel方法来设置该标志

public void cancel() {
  cancelled = true;   
}