Callable与Future的应用

/**
 * CallableAndFuture.java
 * cn.com.songjy.test.socket.thread
 * Function： TODO 
 *
 *   version    date      author
 * ──────────────────────────────────
 *   	1.0	 2013-8-17    songjy
 *
 * Copyright (c) 2013, TNT All Rights Reserved.
 */

package cn.com.songjy.test.socket.thread;

import java.util.Random;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletionService;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorCompletionService;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * ClassName:CallableAndFuture
 * Callable与Future的应用
 * @author songjy
 * @version 1.0
 * @since v1.0
 * @Date 2013-8-17 下午9:13:55
 */

public class CallableAndFuture {

	private static Log log = LogFactory.getLog(CallableAndFuture.class);

	public static void main(String[] args) {
		ExecutorService thread_pools01 = Executors.newSingleThreadExecutor();

		Future<String> future = thread_pools01.submit(new Callable<String>() {

			@Override
			public String call() throws Exception {
				Thread.sleep(5 * 1000l);
				return "hello";
			}
		});

		log.info("等待结果...");

		try {
			// log.info("得到结果："+future.get());//一直等待执行结果
			log.info("得到结果：" + future.get(2, TimeUnit.SECONDS));// 等待2秒，2秒内若未获取到结果则终止任务
		} catch (InterruptedException e) {
			log.error(e.getMessage(), e);
		} catch (ExecutionException e) {
			log.error(e.getMessage(), e);
		} catch (TimeoutException e) {
			log.error(e.getMessage(), e);
		}

		thread_pools01.shutdown();

		ExecutorService thread_pools02 = Executors.newFixedThreadPool(10);// 固定大小线程池

		CompletionService<Integer> completion = new ExecutorCompletionService<Integer>(
				thread_pools02);

		//添加10个任务
		for (int i = 0; i < 10; i++) {
			final int seq = i;
			completion.submit(new Callable<Integer>() {

				@Override
				public Integer call() throws Exception {
					Thread.sleep(new Random().nextInt(5000));
					return seq;

				}
			});
		}
		
		//获取10个任务执行结果
		for(int i=0; i<10; i++) {
			try {
				log.info(completion.take().get());//哪个任务先执行完则打印哪个的结果
			} catch (InterruptedException e) {
				log.error(e.getMessage(), e);
			} catch (ExecutionException e) {
				log.error(e.getMessage(), e);
			}
		}
		
		thread_pools02.shutdown();
	}
}

来自：http://down.51cto.com/data/443429

	public void 线程池() throws InterruptedException, ExecutionException {

		ExecutorService threadPool = Executors.newFixedThreadPool(10);

		List<Future<Integer>> list = new ArrayList<>();

		for (int i = 0; i < 10; i++) {
			Future<Integer> future = threadPool.submit(new Callable<Integer>() {
				public Integer call() throws Exception {

					int i = new Random().nextInt(100);
					System.out.println(i);
					return i;
				}
			});

			list.add(future);
		}

		int sum = 0;

		for (Future<Integer> f : list) {
			sum += f.get();
		}
		System.out.println(sum);

	}