package juc;

import java.util.concurrent.CountDownLatch;

/**

* Created by 李恒名 on 2017/6/18.

*/

public class CountDownLatchTest {

static CountDownLatch latch = new CountDownLatch(3);//创建计数器并设置初始值为3

static void work() {

System.out.println(Thread.currentThread().getName() + " Work End");

latch.countDown();//计数器值-1

}

public static void main(String[] args) throws InterruptedException {

new Thread(() -> work()).start();

new Thread(() -> work()).start();

new Thread(() -> work()).start();

latch.await();//当前线程（主线程）等待计数器值为0，才会执行

System.out.println("Main Thread Work End");

/**

输出：

Thread-0 Work End

Thread-1 Work End

Thread-2 Work End

Main Thread Work End

*/

}

}