JUC并发编程异步回调（十六）

异步回调

Future 设计的初衷 ：对将来的某个事件的结果进行建模

package com.xizi.异步回调;

import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;

public class test {
    public static void main(String[] args) throws ExecutionException, InterruptedException {
//        //没有返回值的 runAsync 异步回调
//        CompletableFuture<Void> completableFuture = CompletableFuture.runAsync(() -> {
//            try {
//                TimeUnit.SECONDS.sleep(2);
//            } catch (InterruptedException e) {
//                e.printStackTrace();
//            }
//            System.out.println(Thread.currentThread().getName() + "runAsync=>Void");
//        });
//        System.out.println("1111111111");
//        completableFuture.get();  //获取阻塞执行结果


        //有返回值 supplyAsync 异步回调
        //ajax 成功和失败的回调
        //返回错误的信息
        CompletableFuture<Integer> completableFuture = CompletableFuture.supplyAsync(() -> {
            System.out.println(Thread.currentThread().getName() + "supplyAsync");
//            int i=10/0;
            return  1024;
        });
        System.out.println(completableFuture.whenComplete((t,u)->{
            System.out.println("t=>"+t);//正常返回的结果
            System.out.println("u=>"+u);//错误信息
        }).exceptionally((e)->{
            System.out.println(e.getMessage());
            return 2333333;
                }).get()
        );

    }
}