通过FutureTask拿到一个线程执行的返回值
如果拿到多个线程的返回值 则组装成List<FutureTask> 然后遍历结果拿到返回值

具体的类
 

package com.qbsea.knowledge.future;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.FutureTask;
import com.qbsea.knowledge.future.model.Card;
public class MainTest {
	public static void main(String[] args) throws InterruptedException, ExecutionException {
		List<String> userIdList = new ArrayList<>();
		userIdList.add("uuid001");
		userIdList.add("uuid002");
		userIdList.add("uuid003");
		//组装任务 
		List<FutureTask<Card>> taskList = new ArrayList<>();
		for (String userId : userIdList) {
			//传递业务参数
			MyBusinessTask myBusinessTask = new MyBusinessTask(userId);
			//拿到任务的返回值
			FutureTask<Card> futureTask = new FutureTask<>(myBusinessTask);
			taskList.add(futureTask);
		}
		//执行任务
		ExecutorService pool = Executors.newFixedThreadPool(4);
		for (FutureTask<Card> futureTask : taskList) {
			pool.submit(futureTask);//执行任务
		}
		//查询任务执行结果
		for (FutureTask<Card> futureTask : taskList) {
			Card card = futureTask.get();
			System.out.println("最后的执行结果为="+card.getCardNo());
		}
		pool.shutdown();
	}
}

任务类的具体实现
 

package com.qbsea.knowledge.future;

import java.util.Random;
import java.util.concurrent.Callable;

import com.qbsea.knowledge.future.model.Card;

public class MyBusinessTask implements Callable<Card> {
	private String userId;
	MyBusinessTask(String userId){
		this.userId = userId;
	}
	@Override
	public Card call() throws Exception {
		//query 卡的信息
		Card card = new Card();
		Random random = new Random();
		String cardNo = userId+"_000000"+random.nextInt(9);
		card.setCardNo(cardNo);
		return card;
	}

}

model类
 

package com.qbsea.knowledge.future.model;

public class Card {
	private String cardNo;

	public String getCardNo() {
		return cardNo;
	}

	public void setCardNo(String cardNo) {
		this.cardNo = cardNo;
	}
}