It's actually the WarStructure that understands it. ;-)
- http://anonsvn.jboss.org/repos/jbossas/trunk/server/src/main/org/jboss/web/deployers/WARStructure.java

Ok, then we're going need different components.xml for JBoss 4.2 and JBoss 5.

https://jira.jboss.org/jira/browse/JBSEAM-3579

Yes, in fact with any Java EE 5 container, we should make it a policy in the examples to assume that the container is taking care of the persistence unit rather than Seam. Seam should only step in when the container isn't willing or able (such as with JBoss AS 4.2).

Just as a side note, it would be really cool if we could have a way to configure the persistence in Seam such that Seam will look for the JNDI name and if that fails, it falls back to having Seam bootstrap the PU. This is a matter of putting both in place and letting Seam pick.

<persistence:managed-persistence-context name="entityManager"
  auto-create="true"
  persistence-unit-jndi-name="java:/appNamePU"
  entity-manager-factory="#{entityManagerFactoryUsedIfNecessary}"/>

<persistence:entity-manager-factory name="entityManagerFactoryUsedIfNecessary"
  persistence-unit-name="appNamePU"
  persistence-unit-jndi-name="java:/appNamePU"/>

This is not vetted yet, but by adding the persistence-unit-jndi-name to the entity manager factory, it could disable Seam bootstrapping if the JNDI lookup returns a hit. Then, the managed persistence context goes through similar logic when it is being created.

-Dan

--
Dan Allen
Software consultant | Author of Seam in Action

http://mojavelinux.com
http://mojavelinux.com/seaminaction

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