工具类CountDownLatch的应用---百米赛跑案例

 package com.aj.thread;

 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;

 /**
  * CountDownLatch的运用，百米赛跑案例
  *
  * @author yaolei
  *
  */
 public class CountDownLatchTest {
     public static void main(String[] args) throws InterruptedException {
         ExecutorService executorService = Executors.newCachedThreadPool();
         CountDownLatch referee = new CountDownLatch(1);// 裁判
         CountDownLatch athlete = new CountDownLatch(8);// 运动员
         Runnable runnable = new Runnable() {
             @Override
             public void run() {
                 try {
                     // 每一个线程代表一个运动员，运动员们等待裁判发枪
                     System.out.println(Thread.currentThread().getName() + "准备");
                     referee.await();// 等待中
                     Thread.sleep((long) (Math.random() + 10000));// 听到枪声，跑起来吧，飞人们
                     System.out.println(Thread.currentThread().getName() + "到达终点");
                     athlete.countDown();
                 } catch (InterruptedException e) {
                     // TODO Auto-generated catch block
                     e.printStackTrace();
                 }

             }
         };
         // 跑8个线程，代表8个运动员参赛
         for (int i = 0; i < 8; i++) {
             executorService.execute(runnable);
         }
         executorService.shutdown();
         // 裁判是主线程，准备发枪
         Thread.sleep((long) (Math.random() + 10000));
         // 时间到,发枪
         referee.countDown();
         System.out.println("321发枪，开始跑！");
         System.out.println("裁判准备记录数据：");
         athlete.await();// 等待运动员跑完
         System.out.println("所有人跑完，裁判数据记录完毕!,第一名是姚磊哦");
     }
 }