Module org.neo4j.driver
Package org.neo4j.driver.internal.reactivestreams

Class InternalReactiveResult

java.lang.Object
org.neo4j.driver.internal.reactivestreams.InternalReactiveResult
All Implemented Interfaces:
ReactiveResult
public class InternalReactiveResult extends Object implements ReactiveResult

  • Constructor Details

    • InternalReactiveResult

      public InternalReactiveResult(RxResultCursor cursor)

  • Method Details

    • keys

      public List<String> keys()
      Description copied from interface: ReactiveResult
      Returns a list of keys.
      Specified by:
      keys in interface ReactiveResult
      Returns:
      a list of keys.

    • records

      public org.reactivestreams.Publisher<Record> records()
      Description copied from interface: ReactiveResult
      Returns a cold unicast publisher of records.

      When the record publisher is subscribed, the query is executed and the result is streamed back as a record stream followed by a result summary. This record publisher publishes all records in the result and signals the completion. However, before completion or error reporting if any, a cleanup of result resources such as network connection will be carried out automatically.

      Therefore, the Subscriber of this record publisher shall wait for the termination signal (complete or error) to ensure that the resources used by this result are released correctly. Then the session is ready to be used to run more queries.

      Cancelling of the record streaming will immediately terminate the propagation of new records. But it will not cancel query execution on the server. When the execution is finished, the Subscriber will be notified with a termination signal (complete or error).

      The record publishing event by default runs in a Network IO thread, as a result no blocking operation is allowed in this thread. Otherwise, network IO might be blocked by application logic.

      This publisher can only be subscribed by one Subscriber once.

      If this publisher is subscribed after ReactiveResult.keys(), then the publishing of records is carried out after the arrival of keys. If this publisher is subscribed after ReactiveResult.consume(), then a ResultConsumedException will be thrown.

      Specified by:
      records in interface ReactiveResult
      Returns:
      a cold unicast publisher of records.

    • consume

      public org.reactivestreams.Publisher<ResultSummary> consume()
      Description copied from interface: ReactiveResult
      Returns a cold publisher of result summary which arrives after all records.

      Subscribing the summary publisher results in the execution of the query followed by the result summary being returned. The summary publisher cancels record publishing if not yet subscribed and directly streams back the summary on query execution completion. As a result, the invocation of ReactiveResult.records() after this method, would receive an ResultConsumedException.

      If subscribed after ReactiveResult.keys(), then the result summary will be published after the query execution without streaming any record to client. If subscribed after ReactiveResult.records(), then the result summary will be published after the query execution and the streaming of records.

      Usually, this method shall be chained after ReactiveResult.records() to ensure that all records are processed before summary.

      This method can be subscribed multiple times. When the summary arrives, it will be buffered locally for all subsequent calls.

      Specified by:
      consume in interface ReactiveResult
      Returns:
      a cold publisher of result summary which only arrives after all records.

    • isOpen

      public org.reactivestreams.Publisher<Boolean> isOpen()
      Description copied from interface: ReactiveResult
      Determine if result is open.

      Result is considered to be open if it has not been consumed (ReactiveResult.consume()) and its creator object (e.g. session or transaction) has not been closed (including committed or rolled back).

      Attempts to access data on closed result will produce ResultConsumedException.

      Specified by:
      isOpen in interface ReactiveResult
      Returns:
      a publisher emitting true if result is open and false otherwise.