java同步器——3——笔记

<pre name="code" class="java">CountDownLatch 实例

package com.module;

import java.util.concurrent.CountDownLatch;
/**
 * 用于描述20个开发人员对模块进行开发，全部开发完之后再进行测试
 * @author lihuafeng
 *
 */
public class ModuleThread implements Runnable{

private CountDownLatch latch;
/**
 * 模块名字
 */
private String name;
/**
 * 开发花费时间
 */
private String time;

public ModuleThread(CountDownLatch latch, String name, String time) {
super();
this.latch = latch;
this.name = name;
this.time = time;
}

@Override
public void run() {
this.work();
latch.countDown();
}

public void work(){
System.out.println(Thread.currentThread().getName() + "->完成模块：" + name + "花费时间：" + time);
}
}

</pre><pre name="code" class="java"><pre name="code" class="java">package com.module;import java.util.concurrent.CountDownLatch;public class TestThread implements Runnable{private CountDownLatch latch;public TestThread(CountDownLatch latch) {super();this.latch = latch;}@Overridepublic void run() {try {latch.await();System.out.println("可以全面开始测试工作！");} catch (InterruptedException e) {e.printStackTrace();}}}

</pre><pre name="code" class="java"><pre name="code" class="java">package com.module;

import java.util.Random;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class CountDownLatchDemo {

public static void main(String[] args) {
Random r = new Random();
CountDownLatch latch = new CountDownLatch(20);
ExecutorService service = Executors.newCachedThreadPool();
service.execute(new TestThread(latch));


for(int i = 0 ; i < 20 ; i ++){
service.execute(new ModuleThread(latch, "模块"+i, r.nextInt(2000)+""));
}
service.shutdown();
}
}

运行结果：

pool-1-thread-2->完成模块：模块0花费时间：276
pool-1-thread-3->完成模块：模块1花费时间：1172
pool-1-thread-4->完成模块：模块2花费时间：977
pool-1-thread-2->完成模块：模块5花费时间：72
pool-1-thread-4->完成模块：模块6花费时间：678
pool-1-thread-3->完成模块：模块4花费时间：1144
pool-1-thread-5->完成模块：模块3花费时间：1177
pool-1-thread-5->完成模块：模块8花费时间：1945
pool-1-thread-3->完成模块：模块9花费时间：882
pool-1-thread-6->完成模块：模块7花费时间：134
pool-1-thread-2->完成模块：模块11花费时间：795
pool-1-thread-12->完成模块：模块19花费时间：1959
pool-1-thread-11->完成模块：模块18花费时间：1432
pool-1-thread-10->完成模块：模块17花费时间：1950
pool-1-thread-9->完成模块：模块16花费时间：928
pool-1-thread-8->完成模块：模块15花费时间：638
pool-1-thread-7->完成模块：模块12花费时间：1324
pool-1-thread-3->完成模块：模块13花费时间：1998
pool-1-thread-5->完成模块：模块14花费时间：1124
pool-1-thread-4->完成模块：模块10花费时间：220
可以全面开始测试工作！