java 停止一個正在運行的線程

中斷（Interrupt）一個線程意味着在該線程完成任務之前停止其正在進行的一切，有效地中止其當前的操作。線程是死亡、還是等待新的任務或是繼續運行至下一步，就取決於這個程序。雖然初次看來它可能顯得簡單，但是，你必須進行一些預警以實現期望的結果。你最好還是牢記以下的幾點告誡。

首先，忘掉Thread.stop方法。雖然它確實停止了一個正在運行的線程，然而，這種方法是不安全也是不受提倡的，這意味着，在未來的JAVA版本中，它將不復存在。

1：

public static void main(String[] args) throws Exception {
        MyThread mt = new MyThread();
        Thread t = new Thread(mt);
        System.out.println("System is ready to start thread");
        t.start();

        Thread.sleep(3000);

        System.out.println("System is ready to stop thread");
        //線程沒有處於阻塞狀態，調用線程對應的interrupt()不能讓運行的線程停止下來
        t.interrupt();
    }

    static class MyThread implements Runnable {

        public volatile boolean stop = false;

        private void dosomethig() throws InterruptedException {
            long time = System.currentTimeMillis();
            while(System.currentTimeMillis() - time < 1000) {

            }
            System.out.println("all things had been done!!");
        }

        @Override
        public void run() {
            try {
                while(!stop) {
                    System.out.println(Thread.currentThread().getName() + " is running..");
                    dosomethig();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                System.out.println(Thread.currentThread().getName() + " is exiting under request.");
            }
        }
    }

運行結果：
System is ready to start thread
Thread-0 is running..
all things had been done!!
Thread-0 is running..
all things had been done!!
Thread-0 is running..
all things had been done!!
Thread-0 is running..
System is ready to stop thread
all things had been done!!
Thread-0 is running..
all things had been done!!
Thread-0 is running..
all things had been done!!
Thread-0 is running..
all things had been done!!
Thread-0 is running..

 

 

2：

public static void main(String[] args) throws Exception {
        MyThread mt = new MyThread();
        Thread t = new Thread(mt);
        System.out.println("System is ready to start thread");
        t.start();

        Thread.sleep(3000);

        System.out.println("System is ready to stop thread");
//      t.interrupt();
        //當線程沒有處於阻塞狀態，通過改變標誌量，可以讓線程停止運行
        mt.stop = true;
    }

運行結果：
System is ready to start thread
Thread-0 is running..
all things had been done!!
Thread-0 is running..
all things had been done!!
Thread-0 is running..
System is ready to stop thread
all things had been done!!
Thread-0 is exiting under request.

 

3：

public static void main(String[] args) throws Exception {
        MyThread mt = new MyThread();
        Thread t = new Thread(mt);
        System.out.println("System is ready to start thread");
        t.start();

        Thread.sleep(3000);

        System.out.println("System is ready to stop thread");
//      t.interrupt();
        //此時線程一直處於阻塞狀態，無法檢查標誌量，所以僅通過改變標誌量無法停止線程
        mt.stop = true;
    }

    static class MyThread implements Runnable {

        public volatile boolean stop = false;

        private void dosomethig() throws InterruptedException {
//          long time = System.currentTimeMillis();
//          while(System.currentTimeMillis() - time < 1000) {
//
//          }
            Thread.currentThread().join();
            System.out.println("all things had been done!!");
        }

        @Override
        public void run() {
            try {
                while(!stop) {
                    System.out.println(Thread.currentThread().getName() + " is running..");
                    dosomethig();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                System.out.println(Thread.currentThread().getName() + " is exiting under request.");
            }
        }
    }

運行結果：
System is ready to start thread
Thread-0 is running..
System is ready to stop thread

4：

public static void main(String[] args) throws Exception {
        MyThread mt = new MyThread();
        Thread t = new Thread(mt);
        System.out.println("System is ready to start thread");
        t.start();

        Thread.sleep(3000);

        System.out.println("System is ready to stop thread");
        //通過調用線程對象上的interrupt() 正在運行的線程對象會接收到一個InterruptedException異常，從而停止運行
                  t.interrupt();
//      mt.stop = true;
    }

運行結果:
System is ready to start thread
Thread-0 is running..
System is ready to stop thread
java.lang.InterruptedException
Thread-0 is exiting under request.
    at java.lang.Object.wait(Native Method)
    at java.lang.Thread.join(Thread.java:1143)
    at java.lang.Thread.join(Thread.java:1196)
    at com.thread.DeadLockTest$MyThread.dosomethig(DeadLockTest.java:29)
    at com.thread.DeadLockTest$MyThread.run(DeadLockTest.java:38)
    at java.lang.Thread.run(Thread.java:619)

 

5：中斷I/O操作

public static void main(String[] args) throws Exception {
        MyThread mt = new MyThread();
        Thread t = new Thread(mt);
        System.out.println("System is ready to start thread");
        t.start();

        Thread.sleep(3000);

        System.out.println("System is ready to stop thread");
        t.interrupt();
        mt.stop = true;
        mt.socket.close();
    }

    static class MyThread implements Runnable {
        public volatile boolean stop = false;
        ServerSocket socket = null;

        private void dosomethig() throws InterruptedException, IOException {
//          long time = System.currentTimeMillis();
//          while(System.currentTimeMillis() - time < 1000) {
//
//          }
//          Thread.currentThread().join();
            socket = new ServerSocket(9999);
            //這裏需要調用Socket對應的close方法 這樣子 被阻塞的線程會接收到一個SocketException 從而停止運行
            socket.accept();
            System.out.println("all things had been done!!");
        }

        @Override
        public void run() {
            try {
                while(!stop) {
                    System.out.println(Thread.currentThread().getName() + " is running..");
                    dosomethig();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                System.out.println(Thread.currentThread().getName() + " is exiting under request.");
            }
        }
    }

運行結果：
System is ready to start thread
Thread-0 is running..
System is ready to stop thread
java.net.SocketException: socket closed
Thread-0 is exiting under request.
    at java.net.PlainSocketImpl.socketAccept(Native Method)
    at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:384)
    at java.net.ServerSocket.implAccept(ServerSocket.java:453)
    at java.net.ServerSocket.accept(ServerSocket.java:421)
    at com.thread.DeadLockTest$MyThread.dosomethig(DeadLockTest.java:33)
    at com.thread.DeadLockTest$MyThread.run(DeadLockTest.java:42)
    at java.lang.Thread.run(Thread.java:619)

 

 

參考》

http://www.blogjava.net/jinfeng_wang/archive/2008/04/27/196477.html