protected SortedSet<OWLClassExpression> getEquivalentClassesImpl(OWLClassExpression ce) { SortedSet<OWLClassExpression> equivalentClasses = new TreeSet<>(); Node<OWLClass> classNodes; try { classNodes = reasoner.getEquivalentClasses(ce); } catch (UnsupportedOperationException e) { if (useFallbackReasoner) { classNodes = fallbackReasoner.getEquivalentClasses(ce); } else { throw e; } } equivalentClasses.addAll(classNodes.getEntitiesMinusTop()); equivalentClasses.remove(ce); return equivalentClasses; }