package com.karl.example; import java.util.concurrent.CountDownLatch; /** * Created by karl. */ public class CountDownLatchExample { public static class Task implements Runnable{ private String name; private CountDownLatch latch; private Long timeToStart; public Task(String name, Long timeToStart, CountDownLatch latch){ this.name = name; this.latch = latch; this.timeToStart = timeToStart; } @Override public void run() { try { Thread.sleep(timeToStart); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println( name + " is Up"); latch.countDown(); //计数器减1 } } public static void main(String[] args) { CountDownLatch latch = new CountDownLatch(3); Thread t1 = new Thread(new Task("Thread 1",1000L,latch)); Thread t2 = new Thread(new Task("Thread 2",1000L,latch)); Thread t3 = new Thread(new Task("Thread 3",1000L,latch)); Thread t4 = new Thread(new Task("Thread 4",1000L,latch)); Thread t5 = new Thread(new Task("Thread 5",1000L,latch)); Thread t6 = new Thread(new Task("Thread 6",1000L,latch)); t1.start(); t2.start(); t3.start(); t4.start(); t5.start(); t6.start(); try { latch.await(); System.out.println("at least 3 thread startup,application is starting now"); } catch (InterruptedException e) { e.printStackTrace(); } } }
结果:
Thread 2 is Up Thread 1 is Up Thread 3 is Up Thread 4 is Up at least 3 thread startup,application is starting now Thread 5 is Up Thread 6 is Up
时间: 2024-10-13 16:21:43