夜光带你走进 Java基础编程实战（二十四线程）

夜光序言：

总有一天，你会遇上那么一个人，让你的欢笑和泪水都有意义~~

正文：

夜光带你走进 Java基础编程实战（二十四线程）

import java.util.concurrent.Phaser;

public class PhaserExample {

   /**
   *
   * 夜光~~
   *
   * 假设举行考试，总共三道大题，每次下发一道题目，等所有学生完成后再进行下一道
   *
   * @param args
   */
   public static void main(String[] args) {

int studentsCnt = 5;
Phaser phaser = new Phaser(studentsCnt);

       for (int i = 0; i < studentsCnt; i++) {
           new Thread(new Student(phaser)).start();
       }
   }
}

class Student implements Runnable {

private final Phaser phaser;

   public Student(Phaser phaser) {
       this.phaser = phaser;
   }

   @Override
   public void run() {
       try {
           doTesting(1);
           phaser.arriveAndAwaitAdvance(); //夜光：等到5个线程都到了，才放行
           doTesting(2);
           phaser.arriveAndAwaitAdvance();
           doTesting(3);
           phaser.arriveAndAwaitAdvance();
       } catch (InterruptedException e) {
           e.printStackTrace();
       }
   }

   private void doTesting(int i) throws InterruptedException {
       String name = Thread.currentThread().getName();
       System.out.println(name + "开始答第" + i + "题");
       long thinkingTime = (long) (Math.random() * 1000);
       Thread.sleep(thinkingTime);
       System.out.println(name + "第" + i + "道题答题结束");
   }
}