I've started to look into doing this and:
1) javax.persistence.Query doesn't really map well to either the OCM
query class nor to the OCM filter class I think that both classes
would have to be heavily refactored or replaced by an implementation
of the JPA Query class.
2) javax.persistence.EntityManager maps more cleanly, however, given
that one needs to have the ability to create queries using EJB QL we
would have to implement some sort of EJB QL parser to translate to sql
or xpath which would be a bit of a pain
I am sure there are more details I haven't dug up. If JPA is super
important we could start working on this as I think there are
advantages for making JCR usage more widespread (it would be nice for
people to be able to move existing apps to this new paradigm as I
think it has benefits in terms of simplifying object - data store
mapping).
-paddy
