15.Java5的CyclicBarrier同步工具

 1 import java.util.concurrent.CyclicBarrier;
 2 import java.util.concurrent.ExecutorService;
 3 import java.util.concurrent.Executors;
 4 
 5 /**
 6  * CyclicBarrier
 7  * 表示大家彼此等待，大家集合好后才开始出发，分散活动后又在指定地点集合碰面，
 8  * 这就好比整个公司的人员利用周末时间集合郊游一样，先各自从家出发到公司集合后，
 9  * 再同时出发到公园游玩，在指定地点集合后再同时开始就餐。
10  * @author LiTaiQing
11  *
12  */
13 public class CyclicBarrierTest {
14     public static void main(String[] args) {
15         ExecutorService service = Executors.newCachedThreadPool();
16         final CyclicBarrier cb = new CyclicBarrier(3);
17         for (int i = 0; i < 3; i++) {
18             Runnable runnable = new Runnable() {
19                 public void run() {
20                     try {
21                         Thread.sleep((long) (Math.random() * 10000));
22                         System.out.println("线程"
23                                 + Thread.currentThread().getName()
24                                 + "即将到达集合地点1，当前已有"
25                                 + (cb.getNumberWaiting() + 1)
26                                 + "个已经到达，"
27                                 + (cb.getNumberWaiting() == 2 ? "都到齐了，继续走啊"
28                                         : "正在等候"));
29                         cb.await();
30 
31                         Thread.sleep((long) (Math.random() * 10000));
32                         System.out.println("线程"
33                                 + Thread.currentThread().getName()
34                                 + "即将到达集合地点2，当前已有"
35                                 + (cb.getNumberWaiting() + 1)
36                                 + "个已经到达，"
37                                 + (cb.getNumberWaiting() == 2 ? "都到齐了，继续走啊"
38                                         : "正在等候"));
39                         cb.await();
40                         Thread.sleep((long) (Math.random() * 10000));
41                         System.out.println("线程"
42                                 + Thread.currentThread().getName()
43                                 + "即将到达集合地点3，当前已有"
44                                 + (cb.getNumberWaiting() + 1)
45                                 + "个已经到达，"
46                                 + (cb.getNumberWaiting() == 2 ? "都到齐了，继续走啊"
47                                         : "正在等候"));
48                         cb.await();
49                     } catch (Exception e) {
50                         e.printStackTrace();
51                     }
52                 }
53             };
54             service.execute(runnable);
55         }
56         service.shutdown();
57     }
58 }