Java：CountDownLatch等待所有线程执行结束后继续执行

CountDownLatch可以使一个或多个线程等待其他线程各自执行完毕后再执行

class WorkThread implements Runnable { private CountDownLatch countDownLatch; public WorkThread(CountDownLatch countDownLatch) { this.countDownLatch = countDownLatch; } @Override public void run() { try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println(Thread.currentThread().getName() + " 干活结束"); this.countDownLatch.countDown(); }
}


  

 

  
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package com.demo.atomic;

import java.util.concurrent.CountDownLatch;

public class countDownLatchDemo { public static void main(String[] args) { // 初始化等待线程个数: 2个 CountDownLatch countDownLatch = new CountDownLatch(2); WorkThread workThread1 = new WorkThread(countDownLatch); WorkThread workThread2 = new WorkThread(countDownLatch); new Thread(workThread1).start(); new Thread(workThread2).start(); // 阻塞主线程，等待子线程全部结束继续 try { countDownLatch.await(); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println("结束了"); }
}


  

 

  
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如果不等待，执行结果

结束了
Thread-0 干活结束
Thread-1 干活结束

  

 

  
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如果等待, 执行结果

Thread-1 干活结束
Thread-0 干活结束
结束了

  

 

  
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文章来源: pengshiyu.blog.csdn.net，作者：彭世瑜，版权归原作者所有，如需转载，请联系作者。

原文链接：pengshiyu.blog.csdn.net/article/details/112249050