线程池的用法

一、不带返回值的线程池方法

 

如果想让他带返回值，需要做一些特殊处理。主要思想如下：

 

 

 

二、带返回值的方法：（http://softstone.javaeye.com/blog/172903）

 

 

package cn.edu.xjtu.nhpcc.jenva.threadpool;

import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

public class TestCall2 {

   float[][] scores = { { 87, 86, 90, 91, 76 }, { 56, 34, 66, 78, 65 },
          { 99, 97, 95, 87, 89 }, { 77, 76, 75, 78, 85 },
          { 88, 56, 78, 78, 76 } };

  Future<Float>[] result = new Future[5];

  public void count() throws InterruptedException, ExecutionException {
      //创建线程池
      ExecutorService pool = Executors.newFixedThreadPool(5);
      for (int i = 0; i < scores.length; i++) {
          //提交任务，获取结果
          result[i] = pool.submit(new Caller(scores[i]));
      }
      for (int i = 0; i < result.length; i++){
          System.out.println(result[i].get());
      }
      //关闭线程池
      pool.shutdown();
  }

  public static void main(String[] args) {
   TestCall2 sample = new TestCall2();
      try{
          sample.count();
      } catch (InterruptedException e) {

          e.printStackTrace();
      } catch (ExecutionException e) {

          e.printStackTrace();
      }
  }
 
  public class Caller implements Callable<Float> {
     private float[] score;

     public Caller(float[] score){
         this.score = score;
     }
     /** *//**
      * 计算平均分
      */
     public Float call() throws Exception {
         float sum = 0;
         for (int i=0;i<score.length;i++){
             sum+=score[i];
         }
         return sum/score.length;
     }
 }
 
}