Are there any relatively mature RDF/OWL Persistence Frameworks I can use?

I have looked at Elmo from openrdf.org, but it doesn't seem to support having object within another object. E.g. Cla开发者_运维百科ss Roof within the Class House and then allow persisting House object.

Is there any other fairly mature and better documented persistence framework out there for RDF/OWL data that will allow such operations? Or if not, is there anything else at all out there?

• RDF triple stores
• Native OWL persistence:
  • OWLDB: http://owldb.sourceforge.net
  • Owlgres: http://pellet.owldl.com/owlgres/

You should check out Empire, it pretty closely implements the JPA spec and sounds like what you are looking for.

Also, fwiw, I believe Elmo can have composite mapped objects.