Hi.
We're migrating from JBoss 5 to JBoss 7(.1.3 final) and wondering, how/if dependency management with JBoss 7 works.
To allow proper initialization and - more importantly - graceful shutdown of our components, we used JBoss 5 specific
dependency declarations using jboss-dependency.xml and jboss.xml (using <depends>). With this, we could declare
EJB-to-EJB, MDB-to-Queue, WAR-to-EJB and even EAR-to-EAR dependencies very nicely. On startup and shutdown all dependencies
were respected accordingly - so e.g. no exceptions were encountered during shutdown and all services were dismantled
in an appropriate order.
It seems that this isn't possible with JBoss 7. The old descriptors aren't valid anymore and the offered alternatives
like jboss-deployment-structure.xml and @DependsOn (JEE standard) don't seem to be sufficient.
Using the jboss-deployment-structure.xml, it seems that this is mainly used for dependency management on classloader
level (visibility) rather than on deployment level. Apparently one can define dependencies on deployment artifact level
(.jars, .wars) but not on EJB level. Also MDB/EJB-to-Queue dependencies seem not possible with this configuration.
Using @DependsOn, as per JEE spec, is limited to EJB Singletons. So one can't define e.g. MDB->EJB (non-singleton)
dependencies as it seems.
What we encounter during our tests is, that e.g. EJBs are shutdown before MDBs that are using them, throwing
exceptions during shutdown like described here: https://community.jboss.org/message/819639#819639. Trying to
use @DependsOn on the MDB referencing the EJB didn't succeed (as expected).
Now, to come back to the origin question, are there any other ways to define dependencies within JBoss 7 as it was
possible with JBoss 5? Maybe we have overlooked some options? What are the best practices to achieve similar
functionality within JBoss 7?
Some insight would be greatly appreciated.
Thanks.
