package org.wzh.cc;

 import java.util.Arrays;

 import java.util.Random;

 import java.util.concurrent.CountDownLatch;

 import java.util.stream.IntStream;

 import static java.lang.System.out;

 public class D4CountDownLatch {

     class Task extends Thread {

         private CountDownLatch latch;

         private int time;

         public Task(CountDownLatch latch) {

             super();

             this.latch = latch;

             time = score();

         }

         private int score() {

             return (new Random().nextInt(8000) + 10000) / 1000;

         }

         @Override

         public void run() {

             // TODO Auto-generated method stub

             try {

                 String name = currentThread().getName();

                 out.println(name + " 预计成绩 " + time + " seconds");

                 out.println(name + " 正在冲刺");

                 sleep(time * 1000);

                 out.println(name + " 到达终点!");

                 latch.countDown();//跑完减一

             } catch (InterruptedException e) {

                 e.printStackTrace();

             }

         }

     }

     public static void main(String[] args) throws InterruptedException {

         out.println("-- 百米赛跑比赛 --");

         out.println("参赛选手:");

         String[] names = {"小明", "小强", "小智"};

         Arrays.stream(names).forEach(out::println);

         out.println("########## 比赛开始 #########");

         CountDownLatch latch = new CountDownLatch(names.length);

         IntStream.range(0, names.length).forEach(i -> {

             Thread t = new D4CountDownLatch().new Task(latch);

             t.setName(names[i]);

             t.start();

         });

         latch.await();//当latch countDown指定的次数之后才会继续向下执行

         out.println("百米赛跑比赛结束");

     }

 }

 package org.wzh.cc;

 import java.util.Arrays;

 import java.util.Random;

 import java.util.concurrent.BrokenBarrierException;

 import java.util.concurrent.CyclicBarrier;

 import java.util.stream.IntStream;

 import static java.lang.System.out;

 public class D4CyclicBarrier {

     class Task extends Thread {

         private CyclicBarrier barrier;

         private int time;

         public Task(CyclicBarrier barrier) {

             super();

             this.barrier = barrier;

             time = score();

         }

         private int score() {

             return (new Random().nextInt(8000) + 10000) / 1000;

         }

         @Override

         public void run() {

             try {

                 String name = currentThread().getName();

                 System.out.println(name + " 预计成绩 " + time + " seconds");

                 barrier.await();//线程阻塞在这边,直到所有参与的线程都到达这里

                 out.println(name + " 正在冲刺");

                 sleep(time * 1000);

                 out.println(name + " 到达终点!");

             } catch (InterruptedException e) {

                 e.printStackTrace();

             } catch (BrokenBarrierException e) {

                 e.printStackTrace();

             }

         }

     }

     public static void main(String[] args) {

         try {

             out.println("-- 百米赛跑比赛 --");

             out.println("参赛选手:");

             String[] names = {"小明", "小强", "小智"};

             Arrays.stream(names).forEach(out::println);

             out.println("########## 比赛开始 #########");

             CyclicBarrier barrier = new CyclicBarrier(names.length + 1);//***

             IntStream.range(0, names.length).forEach(i -> {

                 Thread t = new D4CyclicBarrier().new Task(barrier);

                 t.setName(names[i]);

                 t.start();

             });

             barrier.await();

             System.out.println("百米赛跑比赛结束");

         } catch (Exception e) {

             e.printStackTrace();

         }

     }

 }