java阻塞主线程的实现

1.声明计数器线程个数：   CountDownLatch latch= new CountDownLatch(2);   2.线程启动带参数latch:   Worker worker1= new Worker("zhang san" , 5000, latch);   3.线程启动,主线程阻塞：   worker1.start(); latch.await();   4.线程run()方法中计数器技术开始：   public void run(){   System. out.println("Worker " +workerName +" do work begin at "+sdf.format( new Date()));   doWork(); //工作了   latch.countDown();//工人完成工作，计数器减一   }    5.整体代码Test：    package tets;   import java.text.SimpleDateFormat; import java.util.Date; import java.util.concurrent.CountDownLatch;   public class CountDownLatchTest {                  final static SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd HH:mm:ss" );            public static void main(String[] args) throws InterruptedException {                CountDownLatch latch= new CountDownLatch(2);//两个工人的协作                Worker worker1= new Worker("zhang san" , 5000, latch);                Worker worker2= new Worker("li si" , 8000, latch);                worker1.start(); //                worker2.start(); //                latch.await(); //等待所有工人完成工作                System. out.println("all work done at " +sdf.format(new Date())+" "+Thread.currentThread().getName());            }                                    static class Worker extends Thread{                String workerName;                  int workTime ;                CountDownLatch latch;                public Worker(String workerName ,int workTime ,CountDownLatch latch){                     this.workerName =workerName;                     this.workTime =workTime;                     this.latch =latch;                }                public void run(){                    System. out.println("Worker " +workerName +" do work begin at "+sdf.format( new Date()));                    doWork(); //工作了                    System. out.println("Worker " +workerName +" do work complete at "+sdf.format( new Date()));                     latch.countDown();//工人完成工作，计数器减一                        }                                private void doWork(){                    try {                        Thread. sleep(workTime);                    } catch (InterruptedException e) {                        e.printStackTrace();                    }                }            }                                 }

转载于:https://www.cnblogs.com/beantestng/p/3772845.html