df.getOWLDatatype(XSDVocabulary.STRING.getIRI()), y));
Set<SWRLAtom> head = new TreeSet<>();
head.add(df.getSWRLClassAtom(a, x));
SWRLRule rule = df.getSWRLRule(body, head);
ontology.getOWLOntologyManager().addAxiom(ontology, rule);
ontology = roundTrip(ontology, new ManchesterSyntaxDocumentFormat());
OWLOntology onto2 = roundTrip(ontology,
new ManchesterSyntaxDocumentFormat());
equal(ontology, onto2);
}