CountDownLatch关于比赛的例子

package com.test;

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

public class CountDownLatchTest
{

	/**
	 * @param args
	 */
	public static void main(String[] args)
	{
		final CountDownLatch referee = new CountDownLatch(1); // 1名裁判
		final CountDownLatch athlete = new CountDownLatch(3); // 3个运行员

		ExecutorService pool = Executors.newCachedThreadPool();
		for (int i = 0; i < 3; i++)
		{
			pool.execute(new Runnable()
			{
				public void run()
				{
					System.out.println("运动员："
							+ Thread.currentThread().getName() + "准备就绪！");
					try
					{
						referee.await();
						System.out.println("运动员："
								+ Thread.currentThread().getName() + "开始起跑！");
						Thread.sleep(new Random().nextInt(10000));
					}
					catch (InterruptedException e)
					{
						e.printStackTrace();
					}
					athlete.countDown();
					System.out.println("运行员："
							+ Thread.currentThread().getName() + "完成比赛！");
				}
			});
		}
		
		try
		{
			Thread.sleep(new Random().nextInt(10000));
			System.out.println("裁判："
					+ Thread.currentThread().getName() + "命令发出");
			referee.countDown();   //起跑命令
			System.out.println("裁判："
					+ Thread.currentThread().getName() + "等待结果");
			athlete.await();
			System.out.println("裁判："
					+ Thread.currentThread().getName() + "公布结果");
		}
		catch (InterruptedException e)
		{
			e.printStackTrace();
		}
		
		pool.shutdown();
	}

}