I think you should go for stage 1 and think about stage 2 for later. Stage 2 is quite smart, I like it.
On Feb 17, 2011, at 3:14 PM, Scott Marlow wrote: > On 02/17/2011 03:52 AM, Emmanuel Bernard wrote: >> >> On Feb 16, 2011, at 6:21 PM, Scott Marlow wrote: >> >>> Its a minor change but I would like to make a small enhancement to >>> EntityManager.unwrap(). I would like to support SessionFactory in case >>> I want to use it later in AS7... >> >> I guess the alternatives are: >> - entityManager.unwrap(SessionFactory.class) //not implemented >> - entityManager.unwrap(Session.class).getSessionFactory() >> - ( (HibernateEntityManagerFactory) entityManager.getEntityManagerFactory() >> ) >> >> As you know, I don't feel like an EM should spit *Factories via the unwrap >> method. So for me option #2 is good enough. > > Yeah, applications should be able to use option #2. My question is really > about the injection from a PU into a Hibernate SessionFactory. Should I also > use option #2 internally or wait until EMF.unwrap() is an option in the > future and use that for my injection support? > > I'm trying to avoid breaking applications that might be injecting a PU into a > Hibernate SessionFactory. > > I could do this in stages: > > Stage 1: PU injection would check if the left hand side (target) class is a > Hibernate SessionFactory and handle that with special code. > > Stage 2: PU injection would use EMF.unwrap(LeftHandSideTarget.class) when > the JPA specification supports this in the future. > >> >>> >>> Is this completely silly or just mildly silly? If creating a container >>> managed entity manager doesn't consume a database connection. I propose >>> that its just mildly silly. If its just mildly silly, I might want to >>> use the unwrap functionality to keep the AS injection code generic >>> (covering injecting a PU into a Hibernate SessionFactory). Of course, >>> the other silly part is the idea that I would get an EM from the PU >>> (could lead to unexpected errors if something goes wrong). >> >> I am a bit uncertain on what you want to achieve. > > A generic (dynamic) way to inject (PU/PC) into any PersistenceProvider > supported class. > > At this point, I'm probably better off waiting for > EntityManagerFactory.unwrap support to be added to the spec (rather than > hacking it into EM.unwrap(SessionFactory.Class). Than, we can do the PU -> > SessionFactory properly. > >> Do you want to create a EM that you will not use just to get the >> SessionFactory? >> I'm not sure I like that very much and I would use option #3 to get the >> SessionFactory from the EMF. >> Yes the code requires a cast but you depend on Hibernate classes anyway when >> you need a SessionFactory. > > I think just living with "Stage 1" from above is good enough for AS 7. > >> >>> >>> It might be nice to have an unwrap method on the EntityManagerFactory >>> for this purpose. Is that worth proposing for a future JPA release? >>> >> >> Yep, it's going to be added. >> >> > _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
