[hibernate-dev] Make HibernatePersistenceProvider easier to extend

[Guillaume Smet]

Hi,

I'm starting our migration to ORM 4.3 to be able to provide some
(hopefully useful) feedback on ORM 4.3 and Search 4.5.

One thing we did in most of our apps was injecting Spring managed
interceptor into the session factory using a trick very similar to
what is explained there:
http://blog.krecan.net/2009/01/24/spring-managed-hibernate-interceptor-in-jpa/.

This (kinda ugly) trick doesn't work any more in 4.3 and I ended up
doing the following:
https://gist.github.com/gsmet/8578138
which works but is IMHO very fragile as I only changed one
initialization method and if I would have liked to change them all, I
would have to duplicate a lot of code.

Would it be possible to create a protected method which centralizes
the call to Bootstrap.getEntityManagerFactoryBuilder( persistenceUnit,
integration, providedClassLoader ); call we could override easily?
See:
https://github.com/hibernate/hibernate-orm/blob/4.3/hibernate-entitymanager/src/main/java/org/hibernate/jpa/HibernatePersistenceProvider.java#L129
https://github.com/hibernate/hibernate-orm/blob/4.3/hibernate-entitymanager/src/main/java/org/hibernate/jpa/HibernatePersistenceProvider.java#L150
https://github.com/hibernate/hibernate-orm/blob/4.3/hibernate-entitymanager/src/main/java/org/hibernate/jpa/HibernatePersistenceProvider.java#L157

This way I could simply override this method to return a different
EntityManagerFactoryBuilder aware of my interceptor for every way to
initialize an EntityManagerFactory.

And minor nitpicking, I think the wrap method should be protected as
it's used in a protected method we might want to tweak without having
to implement this method again. see
https://github.com/hibernate/hibernate-orm/blob/4.3/hibernate-entitymanager/src/main/java/org/hibernate/jpa/HibernatePersistenceProvider.java#L137

I can open a Jira issue and do the work if you agree there is
something to fix and we come up with a plan (and a clever method
name).

Thanks for your feedback.

-- 
Guillaume