openllet.modularity.ModularityUtils Maven / Gradle / Ivy

// Copyright (c) 2006 - 2008, Clark & Parsia, LLC. 
// This source code is available under the terms of the Affero General Public
// License v3.
//
// Please see LICENSE.txt for full license terms, including the availability of
// proprietary exceptions.
// Questions, comments, or requests for clarification: [email protected]

package openllet.modularity;

import com.clarkparsia.owlapi.modularity.locality.LocalityClass;
import java.util.Iterator;
import java.util.Set;
import java.util.stream.Collectors;
import openllet.core.utils.iterator.NestedIterator;
import org.semanticweb.owlapi.model.OWLAxiom;
import org.semanticweb.owlapi.model.OWLEntity;
import org.semanticweb.owlapi.model.OWLOntology;
import uk.ac.manchester.cs.owlapi.modularity.ModuleType;

/**
 * @author Evren Sirin
 */
public class ModularityUtils
{
	/**
	 * Extract the module from the imports closure of the given ontology for the given signature. Modules contain axioms related to the signature elements that
	 * describe how they relate to each other. There are four module types supported with the following very rough explanations: lower (top) module
	 * contains subclasses of the signature elements upper (bot) module contains superclasses of the signature elements
 upper-of-lower
	 * (bot_of_top) module extract the upper module from the lower module
 lower-of-upper (top_of_bot) module - extract the lower module from the upper
	 * module
  The module types are closely related to the locality class used. Lower module is extracted with top locality and thus also called top
	 * module.
	 *
	 * @param ontology ontolgoy from which the module is extracted
	 * @param signature set of entities used to extract the module
	 * @param moduleType type of the module
	 * @return a set of axioms representing the relevant axioms for the signature elements
	 */
	public static Set extractModule(final OWLOntology ontology, final Set signature, final ModuleType moduleType)
	{
		return extractModule(ontology.importsClosure().collect(Collectors.toSet()), signature, moduleType);
	}

	/**
	 * Extract the module from a given set of ontologies (but not their imports) for the given signature. Only the axioms in the given set of ontologies is
	 * considered. Only the axioms from the ontologies that explicitly exists in the given set will be included in the module.
	 *
	 * @see #extractModule(OWLOntology, Set, ModuleType)
	 * @param ontologies ontologies from which the module is extracted
	 * @param signature set of entities used to extract the module
	 * @param moduleType type of the module
	 * @return a set of axioms representing the relevant axioms for the signature elements
	 */
	public static Set extractModule(final Set ontologies, final Set signature, final ModuleType moduleType)
	{
		switch (moduleType)
		{
			case TOP:
				return extractTopModule(axiomIterator(ontologies), signature);

			case BOT:
				return extractBottomModule(axiomIterator(ontologies), signature);

			case STAR:
				final Set bottomModule = extractBottomModule(axiomIterator(ontologies), signature);

				return extractTopModule(bottomModule.iterator(), signature);

			default:
				throw new UnsupportedOperationException("Unrecognized module type: " + moduleType);
		}
	}

	private static Iterator axiomIterator(final Set ontologies)
	{
		return new NestedIterator(ontologies)
		{
			@Override
			public Iterator getInnerIterator(final OWLOntology ont)
			{
				return ont.axioms().iterator();
			}
		};
	}

	private static Set extractTopModule(final Iterator axioms, final Set signature)
	{
		return extractModule(axioms, signature, LocalityClass.TOP_TOP);
	}

	private static Set extractBottomModule(final Iterator axioms, final Set signature)
	{
		return extractModule(axioms, signature, LocalityClass.BOTTOM_BOTTOM);
	}

	private static Set extractModule(final Iterator axioms, final Set signature, final LocalityClass localityClass)
	{
		final ModuleExtractor extractor = new AxiomBasedModuleExtractor(localityClass);
		while (axioms.hasNext())
			extractor.addAxiom(axioms.next());
		return extractor.extractModule(signature);
	}

}