Chapter 4. Application development 127
contain. For more information about Publish/Subscribe, see the WebSphere
Business Integration Message Broker help system.
You can also define your own output node if none of the built-in output nodes is
suitable for the protocol or transport type that your business application uses.
Figure 4-30 The built-in output nodes
Most of the samples in the Samples Gallery demonstrate the MQOutput node.
The XML_BuildReplyMessage subflow in the Airline Reservations sample and
the subflow in the Error Handler sample demonstrate the Output node. The
XML_FlightQueryReply message flow in the Airline Reservations sample
demonstrates the MQReply node. The SurfWatch sample (one of the Getting
Started samples), the Soccer Results sample, and the Scribble sample all
demonstrate the Publication node.
4.4.3 Manipulating and transforming the content of messages
If your business is large, it is likely that while the business has developed, many
business applications have been developed. If the applications have been
developed to run on different platforms and they store data in different formats, it
is difficult to send data between them. To help solve this problem, you can
develop message flows that manipulate, or even change the format of, the
messages that the broker receives from one application before it passes them to
To manipulate the content of a message, for example, by modifying the fields
that are included in the output message, or by retrieving information from a
database and including it in the output message, use a
Compute node. You
must program the node using ESQL. The Compute node does not require
that you have externally defined the messages in a message set.
To create a new message from all or some of the data in the input message
by mapping the input fields onto the output fields, use the
Mapping node (for
example, if one application requires that the last name is before the first name
but the other application requires that the first name is before the last name).
If you have externally defined the message structure in a message set, you
can easily produce simple mappings using the mappings editor.