elk-reasoner/src/main/java/org/semanticweb/elk/reasoner/stages/AbstractReasonerState.java
public synchronized Taxonomy<ElkObjectProperty> getObjectPropertyTaxonomyQuietly()
			throws ElkException {
		Taxonomy<ElkObjectProperty> result;

		try {
			result = getObjectPropertyTaxonomy();
		} catch (ElkInconsistentOntologyException e) {
			LOGGER_.debug("Ontology is inconsistent");

			result = new SingletoneTaxonomy<ElkObjectProperty, OrphanTaxonomyNode<ElkObjectProperty>>(
					ElkObjectPropertyKeyProvider.INSTANCE,
					getAllObjectProperties(),
					new TaxonomyNodeFactory<ElkObjectProperty, OrphanTaxonomyNode<ElkObjectProperty>, Taxonomy<ElkObjectProperty>>() {
						@Override
						public OrphanTaxonomyNode<ElkObjectProperty> createNode(
								final Iterable<? extends ElkObjectProperty> members,
								final int size,
								final Taxonomy<ElkObjectProperty> taxonomy) {
							return new OrphanTaxonomyNode<ElkObjectProperty>(
									members, size,
									elkFactory_.getOwlBottomObjectProperty(),
									taxonomy);
						}
					});
		}

		return result;
	}
public synchronized Taxonomy<ElkObjectProperty> getObjectPropertyTaxonomyQuietly()
			throws ElkException {
		Taxonomy<ElkObjectProperty> result;

		try {
			result = getObjectPropertyTaxonomy();
		} catch (ElkInconsistentOntologyException e) {
			LOGGER_.debug("Ontology is inconsistent");

			result = new SingletoneTaxonomy<ElkObjectProperty, OrphanTaxonomyNode<ElkObjectProperty>>(
					ElkObjectPropertyKeyProvider.INSTANCE,
					getAllObjectProperties(),
					new TaxonomyNodeFactory<ElkObjectProperty, OrphanTaxonomyNode<ElkObjectProperty>, Taxonomy<ElkObjectProperty>>() {
						@Override
						public OrphanTaxonomyNode<ElkObjectProperty> createNode(
								final Iterable<? extends ElkObjectProperty> members,
								final int size,
								final Taxonomy<ElkObjectProperty> taxonomy) {
							return new OrphanTaxonomyNode<ElkObjectProperty>(
									members, size,
									elkFactory_.getOwlBottomObjectProperty(),
									taxonomy);
						}
					});
		}

		return result;
	}
Compute the inferred taxonomy of the object properties for the given
ontology if it has not been done yet.

@return the object property taxonomy implied by the current ontology
@throws ElkException
if the reasoning process cannot be completed successfully