OWLOntologyManager mgr = OWLManager.createOWLOntologyManager();
OWLDataFactory factory = mgr.getOWLDataFactory();
OWLObjectProperty op = factory.getOWLObjectProperty(IRI.create(OP));
ObjectProperty jop = null;
try {
jop = j2o.ObjPropOwlToJena(op, RDFXML);
if(jop == null){
fail("Some errore occurs");
}else{
assertEquals(jop.getURI(), op.getIRI().toString());
}