- CountDownLatch：用于监听某些初始化操作，并且线程进行阻塞，等初始化执行完毕后，通知主线程继续工作执行
package com.example.core.juc;import java.util.concurrent.CountDownLatch;public class UseCountDownLatch {public static void main(String[] args) {CountDownLatch countDownLatch = new CountDownLatch(2);//需要两次唤醒Thread t1 = new Thread(new Runnable() {@Overridepublic void run() {System.out.println("进入t1线程");try{Thread.sleep(3000);//做一些初始化准备}catch(InterruptedException e){e.printStackTrace();}System.out.println("t1线程初始化完毕，通知t3线程继续操作");countDownLatch.countDown();//通知t3}},"t1");Thread t2 = new Thread(new Runnable() {@Overridepublic void run() {System.out.println("进入t2线程");try{Thread.sleep(3000);//做一些初始化准备}catch(InterruptedException e){e.printStackTrace();}System.out.println("t2线程初始化完毕，通知t3线程继续操作");countDownLatch.countDown();//通知t3}},"t2");Thread t3 = new Thread(new Runnable() {@Overridepublic void run() {System.out.println("进入t3线程,进入等待阶段");try{countDownLatch.await();//等待阶段，需要唤醒}catch(InterruptedException e){e.printStackTrace();}System.out.println("t3线程 进行后续的操作");}},"t3");t1.start();t2.start();t3.start();}
}
/*
进入t1线程
进入t2线程
进入t3线程,进入等待阶段
t1线程初始化完毕，通知t3线程继续操作
t2线程初始化完毕，通知t3线程继续操作
t3线程 进行后续的操作
*/
