Java实现监控多个线程状态的简单实例

import java.util.concurrent.CountDownLatch;import java.util.concurrent.Executor;import java.util.concurrent.Executors;/** * 测试监控类 *  * @author *  */public class WatchThread { /** * 测试函数 *  * @throws InterruptedException */ public void testThread() throws InterruptedException { int threadNum = 10; // 初始化countDown CountDownLatch threadSignal = new CountDownLatch(threadNum); // 创建固定长度的线程池 Executor executor = Executors.newFixedThreadPool(threadNum); for (int i = 0; i < threadNum; i++) { // 开threadNum个线程  Runnable task = new TestThread(threadSignal);  // 执行  executor.execute(task); } threadSignal.await(); // 等待所有子线程执行完 // do work System.out.println(Thread.currentThread().getName() + "+++++++结束."); } /** * 测试函数 */ public static void main(String[] args) throws InterruptedException { WatchThread test = new WatchThread(); test.testThread(); } /** *  * @author jill *  */ private class TestThread implements Runnable { private CountDownLatch threadsSignal; public TestThread(CountDownLatch threadsSignal) {  this.threadsSignal = threadsSignal; } public void run() {  System.out.println(Thread.currentThread().getName() + "开始...");  // do shomething  System.out.println("开始了线程：：：：" + threadsSignal.getCount());  // 线程结束时计数器减1  threadsSignal.countDown();  //这句代码 建议放在 finally里执行   System.out.println(Thread.currentThread().getName() + "结束. 还有"   + threadsSignal.getCount() + " 个线程"); } }}