Thread_CallableAndFuture(线程池返回结果)

package com.gzhs.zsd.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;

/**

• 线程池Callable与Future应用
  */
  public class Thread_CallableAndFuture {

  public static void main(String[] args) {

   //线程池提交一个任务, 返回结果测试
   //Thread_getFuture();
   
   //线程池提交一组任务, 返回结果测试
   Thread_CompletionService();
  

  }

  //线程提交并拿到Future返回结果
  public static void Thread_getFuture(){
  //创建一个单独线程
  ExecutorService thredPool = Executors.newSingleThreadExecutor();
  //线程池提交, 获取Future结果
  Future future = thredPool.submit(new Callable() {
  @Override
  public String call() throws Exception {
  Thread.sleep(2000);
  return “正常”;
  }
  });

   try {
   	System.out.println("等待检查结果： ");
   	System.out.println("拿到检查结果： " + future.get());
   } catch (InterruptedException e) {
   	e.printStackTrace();
   } catch (ExecutionException e) {
   	e.printStackTrace();
   }
  

  }

  //线程池提交一组Callable任务, 采用take方法获取已完成的的一个Callable任务的Future结果
  public static void Thread_CompletionService(){
  //创建一个10个大小的线程池
  ExecutorService threadPool = Executors.newFixedThreadPool(10);
  //采用CompletionService提交一组任务
  CompletionService completionService = new ExecutorCompletionService(threadPool);
  //循环提交10个人任务
  for(int i = 1; i <= 10; i++){
  final int task = i;
  completionService.submit(new Callable() {
  @Override
  public Integer call() throws Exception {
  //随机等待
  Thread.sleep(new Random().nextInt(10000));
  return task;
  }
  });
  }

   System.out.println("等待检查结果： ");
   //循环拿结果
   for(int i = 1; i<= 10; i++){
   	Future<Integer> future = null;
   	try {
   		//如果，这里没拿到结果, 会一直等待之后， 拿到结果之后， 在往下执行
   		future = completionService.take();
   		System.out.println("拿到检查结果： " + future.get());
   	} catch (InterruptedException e) {
   		e.printStackTrace();
   	} catch (ExecutionException e) {
   		e.printStackTrace();
   	}
   }
  

  }

}