Thread sleep wait notify notifyAll

ThreadWaitSleepDemo.java

public class ThreadWaitSleepDemo {
	public static void main(String[] args) {
		// wait，notify，notifyAll三个方法都有共同点
		// The current thread must own this object's monitor.

		ThreadWaitSleepDemo obj = new ThreadWaitSleepDemo();

		new S(obj).start();

		try {
			synchronized (obj) {
				obj.wait(); // 可以被唤醒或者超时自动醒来
//				Thread.sleep(10 * 1000); // 睡眠的线程无法唤醒，只有超时自动醒来
//				Thread.sleep(0);
			}
		} catch (InterruptedException e) {
			e.printStackTrace();
		}

		System.out.println("i'm awaken!");
	}

	public void wakeMe() {
		this.notify(); // 这是随机的唤醒一个线程，最好用notifyAll，处于该条件的线程都会唤醒，然后有“机会”继续执行
	}
}

class S extends Thread {
	ThreadWaitSleepDemo obj;

	S(ThreadWaitSleepDemo obj) {
		this.obj = obj;
	}

	public void run() {
		ThreadWaitSleepDemo obj = this.obj;
		try {
			Thread.sleep(3 * 1000);
		} catch (InterruptedException e) {
			e.printStackTrace();
		}

		synchronized (obj) {
			obj.wakeMe();
		}
	}
}