CompletableFuture异步编排（多任务组合）

allOf方法：等待所有任务完成。

代码示例

package com.xz.thread.day1;
import lombok.SneakyThrows;
import java.util.concurrent.*;
/**
 * @description: 多任务组合
 *                  allOf：等待所有任务完成
 * @author: xz
 * @create: 2022-08-23
 */
public class Test17 {
    /**
     * 定义线程池
     */
    public static ExecutorService service = Executors.newFixedThreadPool(3);

    @SneakyThrows
    public static void main(String[] args){
        System.out.println("main start ...");

        CompletableFuture future1 = CompletableFuture.supplyAsync(() -> {
            System.out.println("开启异步任务1...");
            return "hello world 1";
        }, service);

        CompletableFuture future2 = CompletableFuture.supplyAsync(() -> {
            System.out.println("开启异步任务2...");
            return "hello world 2";
        }, service);

        CompletableFuture future3 = CompletableFuture.supplyAsync(() -> {
            System.out.println("开启异步任务3...");
            return "hello world 3";
        }, service);

        CompletableFuture future = CompletableFuture.allOf(future1, future2, future3);
        future.get();//等待索引结果完成

        System.out.println("main end ...");
    }
}

输出结果

注：如果不使用future.get()阻塞，若其中一个任务执行时间较长，则可能会丢失任务信息。

anyOf:方法：只要有一个任务完成

代码示例

package com.xz.thread.day1;

import lombok.SneakyThrows;
import java.util.concurrent.*;
/**
 * @description: 多任务组合
 *          anyOf: 只要有一个任务完成
 * @author: xz
 * @create: 2022-08-23
 */
public class Test18 {
    /**
     * 定义线程池
     */
    public static ExecutorService service = Executors.newFixedThreadPool(5);

    @SneakyThrows
    public static void main(String[] args){
        System.out.println("main start ...");

        CompletableFuture future1 = CompletableFuture.supplyAsync(() -> {
            System.out.println("开启异步任务1...");
            return "hello world 1";
        }, service);

        CompletableFuture future2 = CompletableFuture.supplyAsync(() -> {
            try {
                Thread.sleep(500);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("开启异步任务2...");
            return "hello world 2";
        }, service);

        CompletableFuture future3 = CompletableFuture.supplyAsync(() -> {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("开启异步任务3...");
            return "hello world 3";
        }, service);

        CompletableFuture objectCompletableFuture = CompletableFuture.anyOf(future1, future2, future3);
        objectCompletableFuture.get();//等待索引结果完成

        System.out.println("main end ...");
    }
}

输出结果