FutureTask 和 Future

package com.robinboot.facade.test;

import org.junit.Test;

import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import java.util.concurrent.*;

/**
 * @auther: TF12778
 * @date: 2020/4/9 16:03
 * @description:
 */
public class LJFutureTask extends LJTest {

    private final ExecutorService es = new ThreadPoolExecutor(8, 10, 100, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>(5000));

    @Test
    public void getFutureRandomNumTest() {

        // 利用Future獲取隨機數
        Future<Integer> ft = es.submit(new Callable<Integer>() {
            @Override
            public Integer call() throws Exception {

                int num = new Random().nextInt(10);
                TimeUnit.SECONDS.sleep(num);
                return num;
            }
        });

        try {
            int num = ft.get();
            System.out.println(num);
        } catch (InterruptedException e) {
            e.printStackTrace();
        } catch (ExecutionException e) {
            e.printStackTrace();
        }

        System.out.println("########################");
    }

    @Test
    public void futureTaskSumTest() {

        // 利用FutureTask獲取隨機數之和
        Map<String, Future<Integer>> futureMap = new HashMap<>();
        for (int i = 0; i < 10; i++) {
            Future<Integer> fture = es.submit(new Callable<Integer>() {
                @Override
                public Integer call() throws Exception {

                    int num = new Random().nextInt(10);
//                    TimeUnit.SECONDS.sleep(num);
                    return num;
                }
            });
            futureMap.put(i + "", fture);
        }

        int sum = 0;
        for (int i = 0; i < 10; i++) {
            Future<Integer> integerFuture = futureMap.get(i + "");
            try {
                sum = sum + integerFuture.get();
                System.out.println(integerFuture.get());
            } catch (InterruptedException e) {
                e.printStackTrace();
            } catch (ExecutionException e) {
                e.printStackTrace();
            }
        }
        System.out.println(sum);
    }

    @Test
    public void getFutureTaskRandomNumTest() {
        // 利用FutureTask獲取隨機數
        FutureTask<Integer> ftu = new FutureTask<>(new Callable<Integer>() {
            @Override
            public Integer call() throws Exception {

                int num = new Random().nextInt(10);
                TimeUnit.SECONDS.sleep(num);
                return num;
            }
        });

        new Thread(ftu).start();

        try {
            int num = ftu.get();
            System.out.println(num);
        } catch (InterruptedException e) {
            e.printStackTrace();
        } catch (ExecutionException e) {
            e.printStackTrace();
        }
    }
}