Reactive Stream Questions

Douglas Surber douglas.surber at
Tue Jul 31 13:44:27 UTC 2018

Please do not use this thread to discuss the reactive stream proposal. Feel free to discuss the answers to the questions, but not the overall proposal.

Q1: Is Flow.Publisher<Void> ok? I assume only onComplete or onError would be called.

Q2: Which is better, subscribe(Flow.Processor) or subscribe(Flow.Subscriber, Flow.Publisher)?
    This is to replace RowPublisherOperation.subscribe(Flow.Subscriber, CompletionStage).

Q3: Assume DataSource extends Flow.Publisher<Session>.

    ds.flatMap( s -> {
      try(Session session = s.attach()) {
        session.<Employee>rowPublisherOperation(sql) . . .


    ds.flatMap( session -> {
      session.<Employee>rowPublisherOperation(sql) . . .

    The second requires that session only be valid for the duration of the call to onNext.
    The point is that a Session still must be attached and closed. Other alternatives?


More information about the jdbc-spec-discuss mailing list