Interface SegmentPublisherSupplier<R>

Type Parameters:
R -
All Known Subinterfaces:
SegmentAwarePublisherSupplier<R>
public interface SegmentPublisherSupplier<R>
A Publisher that also allows receiving segment completion information if desired. If segment information is needed use publisherWithSegments() which publishes the SegmentPublisherSupplier.Notification instances that can either contain a value or a segment completion notification. In that latter case the notification should be checked if it is for a value SegmentPublisherSupplier.Notification.isValue() or a segment completion SegmentPublisherSupplier.Notification.isSegmentComplete().

After a segment complete notification has been published no other values from that segment will be published again before the publisher completes. Also note that it is possible for a segment to have no values, so there is no guarantee a prior value mapped to a given segment.

If segment completion is not needed, use the Publisher.subscribe(Subscriber). This allows implementors to optimize for the case when segment completion is not needed as this may require additional overhead.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static interface 
    SegmentPublisherSupplier.Notification<R>
    Wrapper around an element returned that can either be a value or a segment completion.

  • Method Summary

    Modifier and Type
    Method
    Description
    org.reactivestreams.Publisher<R>
    publisherWithoutSegments()
    Returns a publisher that can be used to subscribe to the values available.
    org.reactivestreams.Publisher<SegmentPublisherSupplier.Notification<R>>
    publisherWithSegments()
    A Publisher that will publish entries as originally configured from possibly remote sources.

  • Method Details

    • publisherWithoutSegments

      org.reactivestreams.Publisher<R> publisherWithoutSegments()
      Returns a publisher that can be used to subscribe to the values available.
      Returns:
      a Publisher that publishes the resulting values without corresponding segment information

    • publisherWithSegments

      org.reactivestreams.Publisher<SegmentPublisherSupplier.Notification<R>> publisherWithSegments()
      A Publisher that will publish entries as originally configured from possibly remote sources. The published items will be wrapped in a SegmentPublisherSupplier.Notification which can be either an item or segment completion notification. The type can be verified by first invoking SegmentPublisherSupplier.Notification.isValue() or SegmentPublisherSupplier.Notification.isSegmentComplete() after which the value or segment information should be retrieved. Note that each value will also have a segment attributed to it which can be access by invoking SegmentPublisherSupplier.Notification.valueSegment().

      Note that segment completion can be interwoven with values and some segments may have no items present. However, once a segment complete notification is encountered for a given segment no additional values will be published to the same subscriber for the given segment.

      If segment information is not required, please use publisherWithoutSegments() as implementations may have additional optimizations in place for when this information is not required.

      Returns:
      a Publisher that publishes the resulting values with segment information