6.10 Composed Message Processor
Composed Message Processor [EIP] is a higher-order component of a messaging system that accepts a message, breaks it up into submessages that are dispatched and processed by multiple lower-order components, then reassembles submessages into a final message.
In Java CAPS, as in any messaging system, implementation of a Composed Message Processor requires the use of correlations. Superficially, Composed Message Processor pattern is no different from the Scatter-Gather pattern [EIP]. Both involve breaking a message and reassembling the pieces once they are processed by independent intermediate components.
Chapter 11 discusses correlation implementation options provided by Java CAPS and presents a number of correlation examples. Section 11.10.5 provides a Java CAPS example of a Scatter-Gather pattern and Composed Message Processor pattern implementation.