Java線程池ExecutorService和CountDownLatch的小例子

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

/**
 * 模擬了100米賽跑，10名選手已經准備就緒，只等裁判一聲令下。當所有人都到達終點時，比賽結束。
 * @author liuchao
 *
 */
public class Actor {

    public static void main(String[] args) throws InterruptedException {
        //10名運動員
        final CountDownLatch count = new CountDownLatch(10);
        
        //java的線程池
        final ExecutorService executorService = Executors.newFixedThreadPool(5);
        
        for(int index=1;index<=10;index++){
            final int number = index;
            executorService.submit(new Runnable() {
                public void run() {
                    try {

                        Thread.sleep((long) (Math.random()*10000));
                        System.out.println(number+": arrived");
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    } finally{
                        //運動員到達終點,count數減一
                        count.countDown();
                    }
                }
            });
        }
        System.out.println("Game Started");
        //等待count數變為0,否則會一直處於等待狀態,游戲就沒法結束了
        count.await();
        System.out.println("Game Over");
        //關掉線程池
        executorService.shutdown();
    }
}

     運行結果

Game Started
5: arrived
1: arrived
2: arrived
3: arrived
8: arrived
4: arrived
6: arrived
9: arrived
7: arrived
10: arrived
Game Over