java 多线程 day16 CountDownLatch 倒计时计数器

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

public class Thread1601_CountDownLatch {

    public static void main(String[] args) {
        ExecutorService service = Executors.newCachedThreadPool();
        final CountDownLatch cdOrder = new CountDownLatch(1);    //裁判吹口哨，开始跑
        final CountDownLatch cdAnswer = new CountDownLatch(3);   //裁判宣布结果
        for(int i=0;i<3;i++){
            Runnable runnable = new Runnable(){
                public void run(){
                    try {
                        System.out.println("线程" + Thread.currentThread().getName() +
                                "正准备接受命令");
                        cdOrder.await();
                        System.out.println("线程" + Thread.currentThread().getName() +
                                "已接受命令");
                        Thread.sleep((long)(Math.random()*10000));
                        System.out.println("线程" + Thread.currentThread().getName() +
                                "回应命令处理结果");
                        cdAnswer.countDown();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            };
            service.execute(runnable);
        }
        try {
            Thread.sleep((long)(Math.random()*10000));

            System.out.println("线程" + Thread.currentThread().getName() +
                    "即将发布命令");
            cdOrder.countDown();
            System.out.println("线程" + Thread.currentThread().getName() +
                    "已发送命令，正在等待结果");
            cdAnswer.await();
            System.out.println("线程" + Thread.currentThread().getName() +
                    "已收到所有响应结果");
        } catch (Exception e) {
            e.printStackTrace();
        }
        service.shutdown();

    }
}