Hello

I'm currently investigating using Hibernate inside a WebLogic EJB container and was wondering if there were any advantages of storing a SessionFactory object in JNDI as opposed to using the ThreadLocal pattern and storing the SessionFactory in a static variable.
Also, since the EJB container will be clustered, we'll have more than one SessionFactory accessing the same database. Could this potentially pose any problems?

Many thanks in davance

Thomas

Don't put SessionFactory in a thread local variable. It is useful for session storage.
This SF should be unique : use either JNDI or singleton.

Have 1 SF per cluster nodes is just fine.

Yes, sorry that's what I meant. Storing the SessionFactory as a Singleton in a class variable and storing sessions in ThreadLocal.
So there are no advantages of putting the SessionFactory in JNDI over using a Singleton? In that case I better use a Singleton since I don't manage to bind it to the JNDI context in WebLogic.

It has an advantage: classloader headache
If you want to use your SF in your webapp and un your ejbs, then the classloader may be different and the singleton too.
But I personnally keep it in a singleton.

Emmanuel,

Are you sure it is OK to have one SessionFactory shared across several machines in a cluster? I can't find any documentation stating that and I'd be worried that caches, JDBC connections, etc. would be improperly handled when the SessionFactory was serialized and shipped over to another machine in response to a JNDI lookup.

=Jeremy=

It does not work for sure, I haven't said that (I guess ;-) )
Use one SF per JVM.

OK, I'll use one SessionFactoy per JVM.

Just to clarify, you said:

When you use JNDI in a cluster, by default most appservers will replicate a non-managed object such as a SessionFactory across the cluster.

You said:

Normally I wouldn't correct anyone's grammar but in this case what you said is unclear to the point that it could mean either of the two possible choices so I had to ask did you mean a) Having 1 SF for each cluster node is just fine or b) Having 1 SF for the entire cluster is just fine. I understand now that you meant (a). Right?

=Jeremy=

1 session factory per JVM.