package com.test001.www.threadpool;

import java.util.LinkedList;

import java.util.List;

import java.util.Vector;

import java.util.concurrent.Callable;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import java.util.concurrent.Future;

public class ThreadPoolTest {

    public static void main(String[] args){

        ArrayThreadPool<User> pool = new ArrayThreadPool<>();

        for (int i = 5; i > 0; i--){

            Integer data = i;

            pool.submit(()->{
　　　　　　　　　//这个地方可以写一个函数，参数可以从外层传入

               System.out.println("网络操作开始"+data);

               Thread.sleep(data*1000);

               System.out.println("网络操作结束"+data);

               return new User(data);

            });

        }

        List<User> users = pool.get();

        for (User u :users){

            System.out.println(u);

        }

        pool.stop();

    }

}

class User{

    private int i;

    public User(int a){

        i=a;

    }

    @Override

    public String toString() {

        return "user="+i;

    }

}

class ArrayThreadPool<T>{

    private Vector<Future<T>> futureList = new Vector<>();

    ExecutorService executor = Executors.newCachedThreadPool();

    public ArrayThreadPool submit(Callable<T> task){

        Future<T> result = executor.submit(task);

        futureList.add(result);

        return this;

    }

    public List<T> get(){

        List<T> result = new LinkedList<>();

        for (Future<T> future :

                futureList) {

            try {

                result.add(future.get());

            }catch (Exception e){

                result.add(null);

            }

        }

        return result;

    }

    public void stop(){

        executor.shutdown();

    }

}