Re: [jboss-as7-dev] detecting JPA usage in AS7 applications...
On Friday 10 June 2011 01:07 AM, Scott Marlow wrote:
This is wrong I think. We probably only need to look for the presence
of @PersistenceUnit @PersistenceContext and same in deployment
descriptors (which we currently also do).
In earlier versions of JBoss AS, we used
to (optionally) bind the
EntityManager and the EntityManagerFactory to a global JNDI name within
the server. This was a JBoss specific feature (@see
jboss.entity.manager.jndi.name and
jboss.entity.manager.factory.jndi.name in Table 3.1 here
http://docs.jboss.org/ejb3/docs/reference/1.0.7/html/entityconfig.html).
Do we still do this in AS7 or do we plan to do this? Probably allow them
to bind to java:jboss/ namespace?
The reason I ask this is because if we introduce this feature, then just
relying on @PersistenceUnit and @PersistenceContext annotations won't be
enough, since users might lookup the EntityManagerFactory/EntityManager
via JNDI and in such cases too we will require the JPA module
dependencies to be added implicitly.
I don't want to inject the JPA dependencies just because there is
persistence unit definition (we can still parse it and have it available
for use).
This might help us deploy native Hibernate applications that don't use
EE JPA.
I haven't looked at the code related to this (yet), but I'm curious
about how this works and whether this implicit Hibernate dependencies is
going to cause any issues. So:
1) When we say, we are adding implicit JPA dependencies to the
deployment, what exact modules are we adding? JPA spec API module
(javax.persistence.* classes) is fine. Are we adding Hibernate module as
a dependency too?
2) If we are adding a implicit Hibernate dependency, then, is there an
(easy) way for users to specify that this implicit Hibernate dependency
*not* be added? That way, users can package their own version of
Hibernate within their deployments. Note that this is probably going to
be pretty common question from users, because in AS7 we are shipping
Hibernate 4.x version which isn't yet used by many applications.
Hibernate 3.x is the stable version, so I believe users would want to
package that version in their app and use it.
3) If we are adding a implicit Hibernate dependency, then, is there an
(easy) way for users to use a different JPA provider (like EclipseLink)?
-Jaikiran