CountDownLatch测试

package com.coship.locktest;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;

public class CountDownLatchTest {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		/*
		 * try { new CountDownLatchTest.Driver().main(); } catch
		 * (InterruptedException e) { // TODO Auto-generated catch block
		 * e.printStackTrace(); }
		 */
		
		try {
			new CountDownLatchTest.Driver2().main(); 
			} catch (InterruptedException e) { // TODO Auto-generated         catch block
				e.printStackTrace();
			}
	}

	private static class Driver { // ...
		void main() throws InterruptedException {
			CountDownLatch startSignal = new CountDownLatch(1);
			CountDownLatch doneSignal = new CountDownLatch(5);

			for (int i = 0; i < 5; ++i)
				// create and start threads
				new Thread(new Worker(startSignal, doneSignal)).start();

			//执行dowork()方法前处理
			doSomethingElse(); // don't let run yet
			//执行此方法后,dowork()执行
			startSignal.countDown(); // let all threads proceed
			doSomethingElse1();
			doneSignal.await(); // wait for all to finish
		}

		private void doSomethingElse() {
			System.out.println("do doSomethingElse...");
		}

		private void doSomethingElse1() {
			System.out.println("do doSomethingElse1...");
		}
	}

	static class Worker implements Runnable {
		private final CountDownLatch startSignal;
		private final CountDownLatch doneSignal;

		Worker(CountDownLatch startSignal, CountDownLatch doneSignal) {
			this.startSignal = startSignal;
			this.doneSignal = doneSignal;
		}

		public void run() {
			try {
				//所有线程等待
				startSignal.await();
				doWork();
				doneSignal.countDown();
			} catch (InterruptedException ex) {
			} // return;
		}

		void doWork() {
			System.out.println("do work...");
		}
	}

	static class Driver2 { // ...
		void main() throws InterruptedException {
		     CountDownLatch doneSignal = new CountDownLatch(5);
		     Executor e = Executors.newCachedThreadPool();
		 
		      for (int i = 0; i < 5; ++i) // create and start threads
		        e.execute(new WorkerRunnable(doneSignal, i));
		 
		      doneSignal.await();           // wait for all to finish
		      
		      System.out.println("all finished");
		    }
	}

	static class WorkerRunnable implements Runnable {
		private final CountDownLatch doneSignal;
		private final int i;

		WorkerRunnable(CountDownLatch doneSignal, int i) {
			this.doneSignal = doneSignal;
			this.i = i;
		}

		public void run() {
			doWork(i);
			doneSignal.countDown();
		}

		void doWork(int i) {
			System.out.println("do working" + i);
		}
	}
}