org.springframework.messaging.support

Interface ChannelInterceptor

All Known Subinterfaces:

ExecutorChannelInterceptor

All Known Implementing Classes:

ChannelInterceptorAdapter, ImmutableMessageChannelInterceptor

public interface ChannelInterceptor

Interface for interceptors that are able to view and/or modify the Messages being sent-to and/or received-from a MessageChannel.

Since:

4.0

Author:

Mark Fisher, Rossen Stoyanchev

See Also:

Message, MessageChannel

Method Summary

Modifier and Type	Method and Description
default void	afterReceiveCompletion(Message<?> message, MessageChannel channel, Exception ex) Invoked after the completion of a receive regardless of any exception that have been raised thus allowing for proper resource cleanup.
default void	afterSendCompletion(Message<?> message, MessageChannel channel, boolean sent, Exception ex) Invoked after the completion of a send regardless of any exception that have been raised thus allowing for proper resource cleanup.
default Message<?>	postReceive(Message<?> message, MessageChannel channel) Invoked immediately after a Message has been retrieved but before it is returned to the caller.
default void	postSend(Message<?> message, MessageChannel channel, boolean sent) Invoked immediately after the send invocation.
default boolean	preReceive(MessageChannel channel) Invoked as soon as receive is called and before a Message is actually retrieved.
default Message<?>	preSend(Message<?> message, MessageChannel channel) Invoked before the Message is actually sent to the channel.

Method Detail

preSend

@Nullable
default Message<?> preSend(Message<?> message,
                                     MessageChannel channel)

Invoked before the Message is actually sent to the channel. This allows for modification of the Message if necessary. If this method returns null then the actual send invocation will not occur.

postSend

default void postSend(Message<?> message,
                      MessageChannel channel,
                      boolean sent)

Invoked immediately after the send invocation. The boolean value argument represents the return value of that invocation.

afterSendCompletion

default void afterSendCompletion(Message<?> message,
                                 MessageChannel channel,
                                 boolean sent,
                                 @Nullable
                                 Exception ex)

Invoked after the completion of a send regardless of any exception that have been raised thus allowing for proper resource cleanup.

Note that this will be invoked only if preSend(org.springframework.messaging.Message<?>, org.springframework.messaging.MessageChannel) successfully completed and returned a Message, i.e. it did not return null.

Since:

4.1

preReceive

default boolean preReceive(MessageChannel channel)

Invoked as soon as receive is called and before a Message is actually retrieved. If the return value is 'false', then no Message will be retrieved. This only applies to PollableChannels.

postReceive

@Nullable
default Message<?> postReceive(Message<?> message,
                                         MessageChannel channel)

Invoked immediately after a Message has been retrieved but before it is returned to the caller. The Message may be modified if necessary; null aborts further interceptor invocations. This only applies to PollableChannels.

afterReceiveCompletion

default void afterReceiveCompletion(@Nullable
                                    Message<?> message,
                                    MessageChannel channel,
                                    @Nullable
                                    Exception ex)

Invoked after the completion of a receive regardless of any exception that have been raised thus allowing for proper resource cleanup.

Note that this will be invoked only if preReceive(org.springframework.messaging.MessageChannel) successfully completed and returned true.

Since:

4.1