CyclicBarrierDemo

package com.smart.thread;

import java.util.Date;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.CyclicBarrier;

/**

• CyclicBarrier可以在构造时指定需要在屏障前执行await的个数，所有对await的调用都会等待，

• 直到调用await的次数达到预定指，所有等待都会立即被唤醒。

• 从使用场景上来说，CyclicBarrier是让多个线程互相等待某一事件的发生，然后同时被唤醒。

• 而CountDownLatch是让某一线程等待多个线程的状态，然后该线程被唤醒。

• Created by jinxiaoyu on 17/4/11.
  */
  public class CyclicBarrierDemo {
  public static void main(String[] args) throws InterruptedException {
  int totalThread = 5;
  final CyclicBarrier barrier = new CyclicBarrier(totalThread);

   for(int i = 0; i < totalThread; i++) {
       final String threadName = "Thread " + i;
       new Thread() {
           @Override
           public void run() {
               System.out.println(String.format("%s\t%s %s", new Date(), threadName, " is waiting"));
               try {
                   barrier.await();
               } catch (Exception ex) {
                   ex.printStackTrace();
               }
               System.out.println(String.format("%s\t%s %s", new Date(), threadName, "ended"));
           }
       }.start();
   }
  

  }
  }

Tue Apr 11 21:30:19 CST 2017 Thread 1 is waiting
Tue Apr 11 21:30:19 CST 2017 Thread 0 is waiting
Tue Apr 11 21:30:19 CST 2017 Thread 4 is waiting
Tue Apr 11 21:30:19 CST 2017 Thread 3 is waiting
Tue Apr 11 21:30:19 CST 2017 Thread 2 is waiting
Tue Apr 11 21:30:19 CST 2017 Thread 1 ended
Tue Apr 11 21:30:19 CST 2017 Thread 2 ended
Tue Apr 11 21:30:19 CST 2017 Thread 0 ended
Tue Apr 11 21:30:19 CST 2017 Thread 4 ended
Tue Apr 11 21:30:19 CST 2017 Thread 3 ended