O'Reilly - Java Message Service

Java Message Service
Figure 1.5. Dynamically adding auditing and logging using publish-and-subscribe
Figure 1.6. Integration of purchase order system with an ERP system
In Figure 1.6, other JMS applications (A and B) also subscribe to the purchase order topic
and do their own independent processing. Application A might be a legacy application in
the company, while application B may be another company's business system, representing
a B2B integration.
Using JMS, it's fairly easy to add and remove applications from this process. For example,
if purchase orders need to be processed from two different sources, such as an Internetbased
system and a legacy EDI system, you can simply add the legacy purchase order
system to the mix (see Figure 1.7).
14