// create a Sail stack
Sail sail = new MemoryStore();
sail = new ForwardChainingRDFSInferencer(sail);
// create a Repository
Repository repository = new SailRepository(sail);
repository.initialize();
RepositoryConnection con = repository.getConnection();
con.add(a, RDFS.SUBPROPERTYOF, b, defaultContext);
con.add(b, RDFS.SUBPROPERTYOF, c, defaultContext);