Question

我的用例是创建一个像这样的反应性端点：

public Flux<ServerEvent> getEventFlux(Long forId){
    ServicePoller poller = new ServicePollerImpl();
    Map<String,Object> params =  new HashMap<>();
    params.put("id", forId);

    Flux<Long> interval = Flux.interval(Duration.ofMillis(pollDuration));
    Flux<ServerEvent> serverEventFlux =
            Flux.fromStream(
                    poller.getEventStream(url, params) //poll a given endpoint after a fixed duration.
            );
    Flux<ServerEvent> sourceFlux= Flux.zip(interval, serverEventFlux)
             .map(Tuple2::getT2); // Zip the two streams. 
/* Here I want to store data from sourceFlux into a collection whenever some data arrives without disturbing the downstream processing in Spring. So that I can access collection later on without polling again */

这会在数据可用时立即将其发送回前端，但是我的第二个用例是在数据到达一个单独的集合时将其合并，以便如果以后有类似的请求到达，我可以卸载来自池的整个数据而无需再次点击服务。

我试图在从原始流量控制器返回之前，先预订磁通量，缓冲区，缓存并收集流量，但所有这些似乎都关闭了流，因此Spring无法对其进行处理。

在不关闭助焊剂流的情况下，什么时候可以使用助焊剂并将值存储到集合中？

遇到异常：

java.lang.IllegalStateException：流已被操作或在关闭 java.util.stream.AbstractPipeline.spliterator（AbstractPipeline.java:343）〜[na：1.8.0_171]在 java.util.stream.ReferencePipeline.iterator（ReferencePipeline.java:139）〜[na：1.8.0_171]在 Reactor.core.publisher.FluxStream.subscribe（FluxStream.java:57）〜[reactor-core-3.1.7.RELEASE.jar：3.1.7.RELEASE]在 Reactor.core.publisher.Flux.subscribe（Flux.java:6873）〜[reactor-core-3.1.7.RELEASE.jar：3.1.7.RELEASE]在 Reactor.core.publisher.FluxZip $ ZipCoordinator.subscribe（FluxZip.java:573）〜[reactor-core-3.1.7.RELEASE.jar：3.1.7.RELEASE]在 Reactor.core.publisher.FluxZip.handleBoth（FluxZip.java:326）〜[reactor-core-3.1.7.RELEASE.jar：3.1.7.RELEASE]

Answer 1

poller.getEventStream返回一个Java 8流，该流只能使用一次。您可以先将流转换为集合，也可以使用供应商来推迟执行poller.getEventStream：

Flux.fromStream(
  () -> poller.getEventStream(url, params)
);

Answer 2

一个更好的Oliver建议的对我有用的解决方案

public Flux<ServerEvent> getEventFlux(Long forId){
        ServicePoller poller = new ServicePollerImpl();
        Map<String,Object> params =  new HashMap<>();
        params.put("id", forId);

        Flux<Long> interval = Flux.interval(Duration.ofMillis(pollDuration));
        Flux<ServerEvent> serverEventFlux =
                Flux.fromStream(
                        ()->{
                        return poller.getEventStream(url, params).peek((se)->{reactSink.addtoSink(forId, se);});
                        }
                );
        Flux<ServerEvent> sourceFlux= Flux.zip(interval, serverEventFlux)
                 .map(Tuple2::getT2);

        return sourceFlux;

    }

如何在不关闭流的情况下从流量收集

2 个答案: