Interface MessageWriter

All Superinterfaces:
Consumer<org.apache.activemq.artemis.core.server.MessageReference>
All Known Implementing Classes:
AMQPLargeMessageWriter, AMQPMessageWriter, AMQPTunneledCoreLargeMessageWriter, AMQPTunneledCoreMessageWriter, SenderController.RejectingOutgoingMessageWriter
public interface MessageWriter extends Consumer<org.apache.activemq.artemis.core.server.MessageReference>
Message writer for outgoing message from and AMQP sender context which will handle the encode and write of message payload into am AMQP sender.

  • Method Summary

    Modifier and Type
    Method
    Description
    default void
    accept(org.apache.activemq.artemis.core.server.MessageReference messageReference)
    Entry point for asynchronous delivery mechanics which is equivalent to calling the writeBytes(MessageReference) method.
    default void
    close()
    Mark the writer as done and release any resources that it might be holding, this call should trigger the busy method to return false for any handler that has a busy state.
    default boolean
    isWriting()
    This should return true when a delivery is still in progress as a hint to the sender that new messages can't be accepted yet.
    default MessageWriter
    open(org.apache.activemq.artemis.core.server.MessageReference reference)
    Opens the handler and ensures the handler state is in its initial values to prepare for a new message write.
    void
    writeBytes(org.apache.activemq.artemis.core.server.MessageReference messageReference)
    Begin delivery of a message providing the original message reference instance.

    Methods inherited from interface Consumer

    andThen

  • Method Details

    • accept

      default void accept(org.apache.activemq.artemis.core.server.MessageReference messageReference)
      Entry point for asynchronous delivery mechanics which is equivalent to calling the writeBytes(MessageReference) method.
      Specified by:
      accept in interface Consumer<org.apache.activemq.artemis.core.server.MessageReference>
      Parameters:
      messageReference - The original message reference that triggered the delivery.
      See Also:

    • isWriting

      default boolean isWriting()
      This should return true when a delivery is still in progress as a hint to the sender that new messages can't be accepted yet. The handler can be paused during delivery of large payload data due to IO or session back pressure. The context is responsible for scheduling itself for resumption when it finds that it must halt delivery work.

      This could be called from outside the connection thread so the state should be thread safe however the sender should take care to restart deliveries in a safe way taking into account that this value might not get seen by other threads in its non-busy state when the delivery completes.

      Returns:
      true if the handler is still working on delivering a message

    • writeBytes

      void writeBytes(org.apache.activemq.artemis.core.server.MessageReference messageReference)
      Begin delivery of a message providing the original message reference instance. The writer should be linked to a parent sender or sender controller which it will use for obtaining services needed to send and complete sending operations. This must be called from the connection thread.

      Once delivery processing completes (successful or not) the handler must inform the server sender of the outcome so that further deliveries can be sent or error processing can commence.

      Parameters:
      messageReference - The original message reference that triggered the delivery.

    • close

      default void close()
      Mark the writer as done and release any resources that it might be holding, this call should trigger the busy method to return false for any handler that has a busy state. It is expected that the sender will close each handler after it reports that writing the message has completed. This must be called from the connection thread.

    • open

      default MessageWriter open(org.apache.activemq.artemis.core.server.MessageReference reference)
      Opens the handler and ensures the handler state is in its initial values to prepare for a new message write. This is only applicable to handlers that have state data but should be called on every handler by the sender context as it doesn't know which instances need opened.