编辑2

Question

我有以下代码：

/**
*  Request wrapped around flowable.
*/
public abstract class RequestFlowable<T> {

    private final PublishProcessor<String> mPublish;
    private String mName;

    public RequestFlowable(String name) {
        mName = name;
        mPublish = PublishProcessor.create();
    }

    public Flowable<T> getFlowable() {
        //return createAction();
        return mPublish.compose(new FlowableTransformer<String, T>() {
            @Override
            public Publisher<T> apply(@NonNull Flowable<String> upstream) {
                return createAction();
            }
        });
      /*
       return mPublish.flatMap(new Function<String, Publisher<? extends T>>() {
            @Override
            public Publisher<? extends T> apply(@NonNull String s) throws Exception {
                return createAction();
            }
        });
       */

    }

    protected abstract Flowable<T> createAction();


    public String getName() {
        return mName;
    }

    public void start() {
        mPublish.onNext("processCommand");
    }

    @Override
    public String toString() {
        return "Request: " + mName;
    }
}

现在单身 #EDIT 2

public abstract class Request<T> {
    private final SingleSubject<Object> mPublish;
    private String mName;

    public Request(String name) {
        mName = name;
        mPublish = SingleSubject.create();

    }

    public Single<T> getSingle() {
        return mPublish.flatMap(o -> createAction());
    }

    protected abstract Single<? extends T> createAction();


    public String getName() {
        return mName;
    }


    public void start() {
        mPublish.onSuccess("Start");
    }

    @Override
    public String toString() {
        return "Request: " + mName;
    }
}

上面的代码在与compose一起使用时起作用，就像在上面的代码中一样，但是，如果相反我放了注释代码 - 也就是flatMap由于某种原因而不执行createAction。

编辑2

上面的代码是从另一个类调用的。相应的代码附在下面（添加了类的重要部分）：

 public class RequestQueue implements RequestController {
    private static final String TAG = RequestQueue.class.getSimpleName();
    private PublishSubject<Request> mRequest;
    private PublishSubject<RequestFlowable> mRequestFlowable;

    @Override
    public <T> Single<T> registerRequest(Request<T> request) {
        mRequest.onNext(request);
        return request.getSingle();
    }

    @Override
    public <T> Flowable<T> registerRequestFlowable(RequestFlowable<T> request) {
        mRequestFlowable.onNext(request);
        return request.getFlowable();
    }

    public RequestQueue() {
        mRequest = PublishSubject.create();
        mRequestFlowable = PublishSubject.create();
        mRequest.subscribe(this::actionOnRequest);
        mRequestFlowable.subscribe(this::actionOnRequest);
    }

    private void actionOnRequest(Request request) {
        Log.d(TAG, "actionOnRequest() called with: request = [" + request + "]");
        request.start();
    }


    private void actionOnRequest(RequestFlowable request) {
        Log.d(TAG, "actionOnRequest() called with: request = [" + request + "]");
        request.start();
    }
}

Answer 1

（来自我的评论:)

为什么Single有效？

SingleSubject保留收到的单一终端事件。由于它只能接收onSuccess和onError，因此它会重播＆＃34;对于迟到的订阅者（这也就是为什么没有分隔符ReplaySingleSubject）。当您在onSuccess上致电SingleSubject时，会记住该值，并在稍后的订阅发生时重新提交，请致电createAction。 PublishProcessor还会记住其终端事件，但onNext不是终端事件，因此在没有消费者的情况下被删除。

如何通过Processor实现所需的行为？

您可以重新组织逻辑，使用BehaviorProcessor或ReplayProcessor.createWithSize(1)。致电onComplete也不会执行flatMap功能。

PublishProcess flatMap运算符未执行（rxjava-2）

编辑2

1 个答案: