多线程7---volatile关键字,刷新线程工作空间内存到主内存中去,即保持同步

1. 改成static也不行 private static  boolean isRunning = true; volatile关键字主要用于线程变量在多个线程之间的可见

public class RunThread extends Thread{
    private volatile  boolean isRunning = true;
    public void setRunning(boolean isRunning) {
        System.out.println(Thread.currentThread().getName()+"线程setRunning");
        this.isRunning = isRunning;
    }

    public void run(){
        System.out.println(Thread.currentThread().getName()+"进入run方法...");
        while(isRunning) {
            //System.out.println(Thread.currentThread().getName()+"线程isRunning");
        }
        System.out.println(Thread.currentThread().getName()+"线程终止");
    }

    public static void main(String[] args) throws Exception {
        RunThread rt = new RunThread();
        rt.start();
        Thread.sleep(3000);
        rt.setRunning(false);
        System.out.println(Thread.currentThread().getName()+"线程isRunning值被设置成false");
        Thread.sleep(100);
        System.out.println(Thread.currentThread().getName()+"::"+rt.isRunning);
    }
    /* 不加volatile关键字, 主内存中的isRunning不会被刷新,永远都是true.所以线程不会终止,加了会把rt线程的工作内存变量刷新到主内存
     * Thread-0进入run方法...
        main线程setRunning
        main线程isRunning值被设置成false
        main::false
     */
}