In MEDICO we use RDFReactor a generate Java classes from our MEDICO Ontology Hierarchy. This allows us to interact with Java objects at source code level instead of generating RDF statements from scratch.
Problem: Unfortunately RDFReactor does only support RDFS but not OWL. Therefore the unified.owl needs to be adapted like this:
I’ve written a Java program using RDF2Go to perform this conversion. It is far from beeing perfect and generic, but it works for us. You can download it from here.
Meanwhile, Patrick Ernst at DFKI has developed a Maven2 RDFReactor plugin. You can find the documentation and a download link here: http://www.dfki.uni-kl.de/hudson/job/RDFReactorPlugin/site/index.html