package concurrent;import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
/*** 面试题：实现一个容器，提供两个方法，一个size,一个add* 写两个线程，线程1往自定义容器中添加十个元素，线程2实时监控容器中的数量，* 在容器中元素个数为5的时候输出并结束线程* 使用门闩，门闩初始为1，当变为0的时候门闩打开，线程2就受到了通知，输出并结束* @author BarryLee* @2018年11月6日@下午12:49:52*/
public class TestCountDowmLauch {volatile List<Object> list = new ArrayList<>();void add(Object o) {list.add(o);}int size() {return list.size();}public static void main(String[] args) {CountDownLatch latch = new CountDownLatch(1);//TestCountDowmLauch container = new TestCountDowmLauch();// 自定义的容器new Thread(new Runnable() {@Overridepublic void run() {if (container.size() != 5) {try {latch.await();} catch (InterruptedException e) {e.printStackTrace();}}System.out.println("thread2 - end");}}).start();new Thread(new Runnable() {@Overridepublic void run() {for (int i = 0; i < 10; i++) {if (container.size() == 5) {latch.countDown();}try {TimeUnit.SECONDS.sleep(1);} catch (InterruptedException e) {e.printStackTrace();}System.out.println("thread1 - add");container.add(new Object());}}}).start();}
}
/*
thread1 - add
thread1 - add
thread1 - add
thread1 - add
thread1 - add
thread2 - end
thread1 - add
thread1 - add
thread1 - add
thread1 - add
thread1 - add
*/