Package org.eclipse.microprofile.reactive.messaging

Interface Message<T>

Type Parameters:
T - The type of the message payload.
public interface Message<T>
A message envelope.

Messaging providers may provide their own sub classes of this type, in order to allow messaging provider specific information to be passed to and from applications.

  • Method Details

    • of

      static <T> Message<T> of(T payload)
      Create a message with the given payload.
      Type Parameters:
      T - The type of payload
      Parameters:
      payload - The payload.
      Returns:
      A message with the given payload, and a no-op ack function.

    • of

      static <T> Message<T> of(T payload, Supplier<CompletionStage<Void>> ack)
      Create a message with the given payload and ack function.
      Type Parameters:
      T - the type of payload
      Parameters:
      payload - The payload.
      ack - The ack function, this will be invoked when the returned messages ack() method is invoked.
      Returns:
      A message with the given payload and ack function.

    • of

      static <T> Message<T> of(T payload, Supplier<CompletionStage<Void>> ack, Function<Throwable,CompletionStage<Void>> nack)
      Create a message with the given payload, ack and nack functions.
      Type Parameters:
      T - the type of payload
      Parameters:
      payload - The payload.
      ack - The ack function, this will be invoked when the returned messages ack() method is invoked.
      nack - The negative-ack function, this will be invoked when the returned messages nack(Throwable) method is invoked.
      Returns:
      A message with the given payload, ack and nack functions.

    • withPayload

      default <P> Message<P> withPayload(P payload)
      Creates a new instance of Message with the specified payload. The ack/nack functions are taken from the current Message.
      Type Parameters:
      P - the type of the new payload
      Parameters:
      payload - the new payload.
      Returns:
      the new instance of Message

    • withAck

      default Message<T> withAck(Supplier<CompletionStage<Void>> ack)
      Creates a new instance of Message with the given acknowledgement supplier. The payload, and nack function are taken from the current Message.
      Parameters:
      ack - the positive-acknowledgement function
      Returns:
      the new instance of Message

    • withNack

      default Message<T> withNack(Function<Throwable,CompletionStage<Void>> nack)
      Creates a new instance of Message with the given negative-acknowledgement function. The payload and acknowledgment are taken from the current Message.
      Parameters:
      nack - the negative-acknowledgement function
      Returns:
      the new instance of Message

    • getPayload

      T getPayload()
      Returns:
      The payload for this message.

    • ack

      default CompletionStage<Void> ack()
      Acknowledge this message.
      Returns:
      a completion stage completed when the message is acknowledged. If the acknowledgement fails, the completion stage propagates the failure.

    • getAck

      default Supplier<CompletionStage<Void>> getAck()
      Returns:
      the supplier used to retrieve the acknowledgement CompletionStage.

    • getNack

      default Function<Throwable,CompletionStage<Void>> getNack()
      Returns:
      the function used to retrieve the negative-acknowledgement asynchronous function.

    • nack

      default CompletionStage<Void> nack(Throwable reason)
      Acknowledge negatively this message. nack is used to indicate that the processing of a message failed with the reason passed as the parameter.
      Parameters:
      reason - the reason of the nack, must not be null
      Returns:
      a completion stage completed when the message is negative-acknowledgement has completed. If the negative acknowledgement fails, the completion stage propagates the failure.

    • unwrap

      default <C> C unwrap(Class<C> unwrapType)
      Returns an object of the specified type to allow access to the connector-specific Message implementation, and other classes. For example, a Kafka connector could implement this method to allow unwrapping to a specific Kafka message implementation, or to ConsumerRecord and ProducerRecord. If the Message implementation does not support the target class, an IllegalArgumentException should be raised. The default implementation tries to cast the current Message instance to the target class. When a connector provides its own Message implementation, it should override this method to support specific types.
      Type Parameters:
      C - the target type
      Parameters:
      unwrapType - the class of the object to be returned, must not be null
      Returns:
      an instance of the specified class
      Throws:
      IllegalArgumentException - if the current Message instance does not support the call