import org.junit.jupiter.api.Assertions; import org.junit.jupiter.api.Test;

import java.util.Arrays; import java.util.List; import java.util.concurrent.CompletableFuture; import java.util.function.Function; import java.util.stream.Collectors;

public class CompletableFutureTest {

/**
 * 世界上有7颗龙珠,传说集齐7颗龙珠就会实现任意一个愿望,
 * 这7可龙珠分散在世界各地,而你在中国武汉,需要将龙珠搜集在一起,
 * 请编写一段程序来表明你的收集方案
 */
@Test
public void testFindDragonBall(){
    final long s1 = System.currentTimeMillis();
    SevenDragonBall sevenDragonBall = new SevenDragonBall();
    Runnable runnable1 = ()->collectB1(sevenDragonBall);
    Runnable runnable2 = ()->collectB2(sevenDragonBall);
    Runnable runnable3 = ()->collectB3(sevenDragonBall);
    Runnable runnable4 = ()->collectB4(sevenDragonBall);
    Runnable runnable5 = ()->collectB5(sevenDragonBall);
    Runnable runnable6 = ()->collectB6(sevenDragonBall);
    Runnable runnable7 = ()->collectB7(sevenDragonBall);
    final List<Runnable> runnables = Arrays.asList(
            runnable1,
            runnable2,
            runnable3,
            runnable4,
            runnable5,
            runnable6,
            runnable7
    );

    runnables.stream()
            .map((Function<Runnable, CompletableFuture<Void>>) CompletableFuture::runAsync)
            .collect(Collectors.toList())
            .stream()
            .map(CompletableFuture::join)
            .forEach(v->{});

    final long s2 = System.currentTimeMillis();

    Assertions.assertTrue(sevenDragonBall.b1);
    Assertions.assertTrue(sevenDragonBall.b2);
    Assertions.assertTrue(sevenDragonBall.b3);
    Assertions.assertTrue(sevenDragonBall.b4);
    Assertions.assertTrue(sevenDragonBall.b5);
    Assertions.assertTrue(sevenDragonBall.b6);
    Assertions.assertTrue(sevenDragonBall.b7);

    //许愿
    makeAwish();


    Assertions.assertTrue(s2-s1 <= 1000+2000+3000+4000+5000+6000+7000);
}

private void makeAwish() {
    System.out.println("中二病也要谈恋爱");
}

private void collect(long s) {
    try {

        Thread.sleep(s);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}


private void collectB1(SevenDragonBall sevenDragonBall){
    collect(1000);
    sevenDragonBall.b1 = true;
}


private void collectB2(SevenDragonBall sevenDragonBall){
    collect(2000);
    sevenDragonBall.b2 = true;
}

private void collectB3(SevenDragonBall sevenDragonBall){
    collect(3000);
    sevenDragonBall.b3 = true;
}

private void collectB4(SevenDragonBall sevenDragonBall){
    collect(4000);
    sevenDragonBall.b4 = true;
}

private void collectB5(SevenDragonBall sevenDragonBall){
    collect(5000);
    sevenDragonBall.b5 = true;
}

private void collectB6(SevenDragonBall sevenDragonBall){
    collect(6000);
    sevenDragonBall.b6 = true;
}

private void collectB7(SevenDragonBall sevenDragonBall){
    collect(7000);
    sevenDragonBall.b7 = true;
}

static class SevenDragonBall{
    boolean b1;
    boolean b2;
    boolean b3;
    boolean b4;
    boolean b5;
    boolean b6;
    boolean b7;
}

}

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