测试 多线程 实现 callable 带返回值

package threadTest;

import java.util.ArrayList;
import java.util.Date;
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;

/**
 * 
 * 类  描  述： 测试 多线程 实现 callable 带返回值
 * 作        者： 赵         鹏
 */
public class FutureTest {

    @SuppressWarnings("rawtypes")
    public static void main(String[] args) throws InterruptedException, ExecutionException {
        
        Date date1 = new Date();
        
        //线程池大小
        int taskSize = 5;
        
        //1创建一个线程池
        ExecutorService pool = Executors.newFixedThreadPool(taskSize);
        
        //2创建多个砝码绘制的List
        
        ArrayList<Future> list = new ArrayList<Future>();
        
        for (int i = 0; i < taskSize; i++) {
            
            Callable mCallable = new MCallable(i + "");
            //执行任务并获取任务对象
            @SuppressWarnings("unchecked")
            Future future = pool.submit(mCallable);
            
            //System.out.println("【>>>>>】" + future.get().toString());
            //将任务对象存入list中
            list.add(future);
        }
        
        //关闭线程组
        pool.shutdown();
        
        for (Future future : list) {
            
            // 从Future对象上获取任务的返回值，并输出到控制台  
            System.out.println(">>>" + future.get().toString());  
        }
        
        Date date2 = new Date();
        
        System.out.println("[程序执行完成的花费时间为]" + (date2.getTime()-date1.getTime()) + "毫秒");
        
    }
    
}


class MCallable implements Callable<Object> {

    private String taskNum;
    
    MCallable(String taskNum) {
        super();
        this.taskNum = taskNum;
    }
    
    @Override
    public Object call() throws Exception {
        System.out.println(">>> " + taskNum + " 任务开始运行");
        
        Date dateTemp1 = new Date();
        
        Thread.sleep(1000);
        
        Date dateTemp2 = new Date();
        
        long time = dateTemp2.getTime() - dateTemp1.getTime();
        
        System.out.println(">>>" +taskNum+ "任务【结束】运行");
        
        return "任务" +taskNum+ "执行完毕  ， 运行时间为【" + time +"】毫秒";
    }
    
    
    
}