import java.util.concurrent.CompletableFuture;

import java.util.concurrent.ExecutionException;

import java.util.concurrent.TimeUnit;

public class Demo {

    public static void main(String[] args) throws ExecutionException, InterruptedException {

        test02();

    }

    /**

     * 无结果异步回调

     *

     * @throws ExecutionException

     * @throws InterruptedException

     */

    public static void test01() throws ExecutionException, InterruptedException {

        CompletableFuture<Void> completableFuture = CompletableFuture.runAsync(() -> {

            try {

                TimeUnit.SECONDS.sleep(2);

            } catch (InterruptedException e) {

                e.printStackTrace();

            }

            System.out.println(Thread.currentThread().getName() + "runAsync");

        });

        System.out.println("1111111111");

        //获取执行结果

        completableFuture.get();

    }

    /**

     * 有结果异步回调

     *

     * @throws ExecutionException

     * @throws InterruptedException

     */

    public static void test02() throws ExecutionException, InterruptedException {

        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); // 错误信息：

        }).exceptionally((e) -> {

            System.out.println(e.getMessage());

            return 233; // 可以获取到错误的返回结果

        }).get());

    }

}