一个同步辅助类,在完成一组正在其他线程中执行的操作之前,它允许一个或多个线程一直等待。
下面使用了两个倒计数锁存器:即一个等待另一个的完成
import java.util.concurrent.CountDownLatch; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; public class CountDownLatchTest { /** * @param args */ public static void main(String[] args) { ExecutorService ThreadPool = Executors.newCachedThreadPool(); final CountDownLatch cdOrder = new CountDownLatch(1); final CountDownLatch cdAnswer = new CountDownLatch(3); for(int i=0;i<3;i++){ Runnable runnable = new Runnable() { @Override public void run() { try { System.out.println("线程 " + Thread.currentThread().getName() + " 正在等待接受命令"); cdOrder.await(); System.out.println("线程 " + Thread.currentThread().getName() + " 已接受命令"); Thread.sleep((long)Math.random()*10000); System.out.println("线程 " + Thread.currentThread().getName() + " 回应命令,处理结果"); cdAnswer.countDown(); } catch (InterruptedException e) { e.printStackTrace(); } } }; ThreadPool.execute(runnable); } try { Thread.sleep((long)Math.random()*10000); System.out.println("线程 " + Thread.currentThread().getName() + " 正在等待发布命令"); cdOrder.countDown(); cdAnswer.await(); System.out.println("线程 " + Thread.currentThread().getName() + " 已发布命令,正在等待结果"); System.out.println("所有命令都处理完"); } catch (InterruptedException e) { e.printStackTrace(); } ThreadPool.shutdown(); } }
原文地址:http://blog.csdn.net/u012516914/article/details/40798649