package JUC_Study.future;

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

public class FutureDemo {
    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("1111111");
//
//        completableFuture.get(); // 获取阻塞执行结果

        /*
        有返回值的 supplyAsync 异步回调
        返回的是错误信息
         */
        CompletableFuture<Integer> completableFuture = CompletableFuture.supplyAsync(()->{
            System.out.println(Thread.currentThread().getName()+"supplyAsync=>Integer");
            int i = 10/0;
            return 1024;
        });

        System.out.println(completableFuture.whenComplete((t,u)->{
            System.out.println("t=>" + t); // 正常的返回结果
            System.out.println("u=>" + u); // 错误的信息
        }).exceptionally((e)->{
            System.out.println(e.getMessage());
            return 233; // 可以获取到错误的返回结果
        }).get());
    }
}