Message oriented Middleware (MOM)
OAproject's core is a message oriented middleware to allow applications communicate (using for instance OAproject tools).
OAproject pretends to be independent from the message oriented middleware by providing tools to publish/subscribe messages in the different MOM's in a common way. Right now only tools for xmlblaster have been developed. Xmlblaster can be downloaded from it's own site, although OAproject provides binary packages.
Every message in the MOM is assigned to a topic and each application publishes in its own topic. This means that if application A wants to listen to information published by application B, application A must be subscribed to topic B.
The following graphic illustrates the way information is classified inside the MOM:
In this example, applications B and C would be subscribed to topic A, while nobody would be listening to their publications. Every applications publishes to its own topic.
OAproject tools
OAproject tools exist to make adapting applications to the platform less difficult. With them web applications should be able to publish messages and subscribe to topics, at the same time that application adaptation becomes independent from the middleware. An extended explanation of their usage can be found here.
Downloads
Both packages (MOM and OAproject tools) ara available here.