CompletableFuture 示例

horro

package com.sykean.smartsite.pay.MyTest;

import java.util.Random;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.function.Supplier;

/**
* @AuThor Administrator
* @ClassName TestCompletableFuture
* @description futrue测试
* @date 2020/6/16 0016 14:42
* @modifier Administrator
* @date 2020-06-16 14:42
* @version V1.0
*/
public class TestCompletableFuture {

    public static void main(String[] args) throws Exception{
//        test1();
        test2();
//        thenCombine();
    }

    /***
     * 把两个任务的结果一块交给 thenCombine 来处理
     */
    private static void thenCombine() throws ExecutionException, InterruptedException {
        CompletableFuture<String> future1 = CompletableFuture.supplyAsync( () -> "then" );
        CompletableFuture<String> future2 = CompletableFuture.supplyAsync( () -> "Combine" );
        CompletableFuture<String> data = future1.thenCombine( future2, (s, s2) -> s + " " + s2 );
        System.out.println("thenCombine执行结果:{}" + data.get());
    }

    private static void test2() throws ExecutionException, InterruptedException {
        CompletableFuture<String> future1 = CompletableFuture.supplyAsync(() -> {
            System.out.println("做第一件事");
            waitSomeTime(1000);
            return "做第一件事";
        });
        CompletableFuture<String> future2 = CompletableFuture.supplyAsync(() -> {
            System.out.println("做第二件事");
            waitSomeTime(2000);
            return "做第二件事";
        });
        CompletableFuture futureAll = CompletableFuture.allOf(future1,future2);

        System.out.println("开始阻塞" + System.currentTimeMillis());
        futureAll.join();
        System.out.println("结束阻塞" + System.currentTimeMillis());

        System.out.println(future1.isDone());

        if (futureAll.isDone()){
            System.out.println(future1.get());
            System.out.println(future2.get());
            System.out.println("总事件完成");
        }
    }

    private static void waitSomeTime(int i) {
        try {
            Thread.sleep(i);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    private static Supplier<String> getStringSupplier() {
        return String::new;
    }

    private static void test1() throws Exception{
        Random rand = new Random();
        CompletableFuture<Integer> future9 = CompletableFuture.supplyAsync(() -> {
            waitSomeTime(1000 + rand.nextInt(1000));
            return 100;
        });
        CompletableFuture<Integer> future10 = CompletableFuture.supplyAsync(() -> {
            waitSomeTime(1000 + rand.nextInt(1000));
            return 200;
        });
        //两个中任意一个计算完成,那么触发Runnable的执行
        CompletableFuture<String> f = future10.applyToEither(future9, i -> i.toString());
        //两个都计算完成,那么触发Runnable的执行
        CompletableFuture f1 = future10.acceptEither(future9, (e) -> {
            System.out.println(e);
        });
        System.out.println(f.get());
    }
}