@jndiPattern@ is just a markup for a filterset, your build will replace it by the appropriate jndi pattern
is the same as
Where can I find more information about filtersets?
@jndiPattern@ is mostly use -I think- to run tests... with this annotation, your components.xml gets changed at runtime without having to change your components.xml each time
For example, if you run your integration tests on Embedded JBoss, it'd use the jndiPattern defined in the components.properties that is in your classpath (for tests) but once you run your application on the application server, it'd use another jndiPattern:
I'm no expert but that's the only thing that I can think of...