1.interrupt() 中断线程
* <p> If this thread is blocked in an invocation of the {@link
* Object#wait(long, int) wait(long, int)} methods of the {@link Object}
* class, or of the {@link #join()}, {@link #join(long)}, {@link
* #join(long, int)}, {@link #sleep(long)}, or {@link #sleep(long, int)},
* methods of this class, then its interrupt status will be cleared and it
* will receive an {@link InterruptedException}.
* Object#wait() wait()}, {@link Object#wait(long) wait(long)}, or {@link
也就是只有在wait,join,sleep的时候才能抛出interruptedException,并且清除了中断状态,其他情况不会抛出中断异常
通过代码证明下
a.第一种情况 在不是wait,join,sleep的时候调用interrupt方法
public class Interrupt1 {
public static void main(String[] args) throws InterruptedException {
ThreadTest thread=new ThreadTest();
Thread t=new Thread(thread);
t.start();
Thread.sleep(1000);
t.interrupt();
System.out.println("main 线程执行完毕");
}
public static class ThreadTest implements Runnable{
public void run() {
Thread curr=Thread.currentThread();
System.out.println("===="+curr.isInterrupted());
while(true){
if(curr.isInterrupted()){
System.out.println("===="+curr.isInterrupted());
break;
}
if(1==2)
break;
}
System.out.println("^^^^^^^");
}
}
}
====false
main 线程执行完毕
====true
^^^^^^^
从结果可以看出并没有抛出interruptException，并且curr.isInterrupted方法返回了ture，说明中断状态也没有被清除
b.在sleep的时候在调用interrupte方法看下什么情况，run方法加下sleep
Thread curr=Thread.currentThread();
System.out.println("===="+curr.isInterrupted());
while(true){
try {
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
System.out.println("==="+curr.isInterrupted());
}
if(curr.isInterrupted())
System.out.println("000000000");
if(1==2)
break;
}
System.out.println("^^^^^^^");
执行结果：
====false
main 线程执行完毕
java.lang.InterruptedException: sleep interrupted
===false
at java.lang.Thread.sleep(Native Method)
at a.Interrupt1$ThreadTest.run(Interrupt1.java:22)
at java.lang.Thread.run(Unknown Source)
确实抛出了interruptedException,并且isinterrupted()返回了false说明中断状态被清除了，后面的判断就不管用了，所以拿这个方法中断线程还是不安全，自己用变量控制更靠谱
2.静态方法public static boolean interrupted()
* Tests whether the current thread has been interrupted. The
* <i>interrupted status</i> of the thread is cleared by this method. In
* other words, if this method were to be called twice in succession, the
* second call would return false (unless the current thread were
* interrupted again, after the first call had cleared its interrupted
* status and before the second call had examined it).
检查当前中断状态，并且清除中断状态，连续调用2此的第二次肯定返回false
Thread curr=Thread.currentThread();
System.out.println("===="+curr.isInterrupted());
while(true){
try {
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
curr.interrupt();
System.out.println("先变成true==="+curr.isInterrupted());
System.out.println("curr.isInterrupted==="+Thread.interrupted());
System.out.println("中断状态清除:"+curr.isInterrupted());
System.out.println("curr.isInterrupted==="+Thread.interrupted());
System.out.println("====c"+curr.isInterrupted());
}
if(curr.isInterrupted())
System.out.println("000000000");
if(1==2)
break;
}
System.out.println("^^^^^^^");
}执行结果: