reactor3 flux的map與flatMap的區別

時間 2019-12-04

標籤 reactor3 reactor flux map flatmap 區別欄目 React 简体版

原文原文鏈接

序

本文主要研究一下flux的map與flatMap的區別react

map

@Test
    public void testMap() throws InterruptedException {
        Flux.just(1, 2, 3, 4)
                .log()
                .map(i -> {
                    try {
                        TimeUnit.SECONDS.sleep(1);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    return i * 2;
                })
                .subscribe(e -> LOGGER.info("get:{}",e));
    }

這裏頭的map是純元素轉換

輸出異步

10:53:57.058 [main] INFO reactor.Flux.Array.1 - | onSubscribe([Synchronous Fuseable] FluxArray.ArraySubscription)
10:53:57.062 [main] INFO reactor.Flux.Array.1 - | request(unbounded)
10:53:57.063 [main] INFO reactor.Flux.Array.1 - | onNext(1)
10:53:58.067 [main] INFO com.example.demo.FluxTest - get:2
10:53:58.067 [main] INFO reactor.Flux.Array.1 - | onNext(2)
10:53:59.071 [main] INFO com.example.demo.FluxTest - get:4
10:53:59.071 [main] INFO reactor.Flux.Array.1 - | onNext(3)
10:54:00.076 [main] INFO com.example.demo.FluxTest - get:6
10:54:00.076 [main] INFO reactor.Flux.Array.1 - | onNext(4)
10:54:01.080 [main] INFO com.example.demo.FluxTest - get:8
10:54:01.081 [main] INFO reactor.Flux.Array.1 - | onComplete()

flatMap

@Test
    public void testFaltMap() throws InterruptedException {
        Flux.just(1,2,3,4)
                .log()
                .flatMap(e -> {
                    return Flux.just(e*2).delayElements(Duration.ofSeconds(1));
                })
                .subscribe(e -> LOGGER.info("get:{}",e));
        TimeUnit.SECONDS.sleep(10);
    }

這裏的flatMap，將元素轉爲Mono或Flux，轉換操做裏頭還能夠進行異步操做

輸出code

10:54:01.088 [main] INFO reactor.Flux.Array.2 - | onSubscribe([Synchronous Fuseable] FluxArray.ArraySubscription)
10:54:01.089 [main] INFO reactor.Flux.Array.2 - | request(256)
10:54:01.089 [main] INFO reactor.Flux.Array.2 - | onNext(1)
10:54:01.137 [main] INFO reactor.Flux.Array.2 - | onNext(2)
10:54:01.137 [main] INFO reactor.Flux.Array.2 - | onNext(3)
10:54:01.138 [main] INFO reactor.Flux.Array.2 - | onNext(4)
10:54:01.138 [main] INFO reactor.Flux.Array.2 - | onComplete()
10:54:02.143 [parallel-1] INFO com.example.demo.FluxTest - get:2
10:54:02.143 [parallel-1] INFO com.example.demo.FluxTest - get:4
10:54:02.143 [parallel-1] INFO com.example.demo.FluxTest - get:6
10:54:02.143 [parallel-1] INFO com.example.demo.FluxTest - get:8