ExecutorChannelInterceptor.beforeHandle

Invoked inside the {@link Runnable} submitted to the Executor just before calling the target MessageHandler to handle the message. Allows for modification of the Message if necessary or when {@code null} is returned the MessageHandler is not invoked. @param message the message to be handled @param channel the channel on which the message was sent to @param handler the target handler to handle the message @return the input message, or a new instance, or {@code null}