ontclassimpl.java

Jena推理机

/*****************************************************************************
 * Source code information
 * -----------------------
 * Original author    Ian Dickinson, HP Labs Bristol
 * Author email       [e-mail]
 * Package            Jena 2
 * Web                http://sourceforge.net/projects/jena/
 * Created            27-Mar-2003
 * Filename           $RCSfile: OntClassImpl.java,v $
 * Revision           $Revision: 1.53 $
 * Release status     $State: Exp $
 *
 * Last modified on   $Date: 2007/01/02 11:49:47 $
 *               by   $Author: andy_seaborne $
 *
 * (c) Copyright 2002, 2003, 2004, 2005, 2006, 2007 Hewlett-Packard Development Company, LP
 * (see footer for full conditions)
 *****************************************************************************/

// Package
///////////////
package com.hp.hpl.jena.ontology.impl;



// Imports
///////////////
import com.hp.hpl.jena.ontology.*;
import com.hp.hpl.jena.enhanced.*;
import com.hp.hpl.jena.graph.*;
import com.hp.hpl.jena.graph.query.*;
import com.hp.hpl.jena.rdf.model.*;
import com.hp.hpl.jena.reasoner.*;
import com.hp.hpl.jena.util.iterator.*;
import com.hp.hpl.jena.vocabulary.*;

import java.util.*;


/**
 * <p>
 * Implementation of the ontology abstraction representing ontology classes.
 * </p>
 *
 * @author Ian Dickinson, HP Labs
 *         (<a  href="mailto:[e-mail]" >email</a>)
 * @version CVS $Id: OntClassImpl.java,v 1.53 2007/01/02 11:49:47 andy_seaborne Exp $
 */
public class OntClassImpl
    extends OntResourceImpl
    implements OntClass
{
    // Constants
    //////////////////////////////////

    /* LDP never returns properties in these namespaces */
    private static final String[] IGNORE_NAMESPACES = new String[] {
            OWL.NS,
            DAMLVocabulary.NAMESPACE_DAML_2001_03_URI,
            RDF.getURI(),
            RDFS.getURI(),
            ReasonerVocabulary.RBNamespace
    };


    // Static variables
    //////////////////////////////////

    /**
     * A factory for generating OntClass facets from nodes in enhanced graphs.
     * Note: should not be invoked directly by user code: use
     * {@link com.hp.hpl.jena.rdf.model.RDFNode#as as()} instead.
     */
    public static Implementation factory = new Implementation() {
        public EnhNode wrap( Node n, EnhGraph eg ) {
            if (canWrap( n, eg )) {
                return new OntClassImpl( n, eg );
            }
            else {
                throw new ConversionException( "Cannot convert node " + n.toString() + " to OntClass: it does not have rdf:type owl:Class or equivalent");
            }
        }

        public boolean canWrap( Node node, EnhGraph eg ) {
            // node will support being an OntClass facet if it has rdf:type owl:Class or equivalent
            Profile profile = (eg instanceof OntModel) ? ((OntModel) eg).getProfile() : null;
            return (profile != null)  &&  profile.isSupported( node, eg, OntClass.class );
        }
    };


    // Instance variables
    //////////////////////////////////

    /** Query for properties with this class as domain */
    protected BindingQueryPlan m_domainQuery;

    /** Query for properties restricted by this class */
    protected BindingQueryPlan m_restrictionPropQuery = null;


    // Constructors
    //////////////////////////////////

    /**
     * <p>
     * Construct an ontology class node represented by the given node in the given graph.
     * </p>
     *
     * @param n The node that represents the resource
     * @param g The enh graph that contains n
     */
    public OntClassImpl( Node n, EnhGraph g ) {
        super( n, g );

        // pre-built queries
        // ?x a rdf:Property ; rdfs:domain this.
        Query q = new Query();
        q.addMatch( Query.X, getProfile().DOMAIN().asNode(), asNode() );

        m_domainQuery = getModel().queryHandler().prepareBindings( q, new Node[] {Query.X} );

        // this rdfs:subClassOf ?x. ?x owl:onProperty ?y.
        if (getProfile().ON_PROPERTY() != null) {
            q = new Query();
            q.addMatch( asNode(), getProfile().SUB_CLASS_OF().asNode(), Query.X );
            q.addMatch( Query.X, getProfile().ON_PROPERTY().asNode(), Query.Y );

            m_restrictionPropQuery = getModel().queryHandler().prepareBindings( q, new Node[] {Query.Y} );
        }
    }


    // External signature methods
    //////////////////////////////////

    // subClassOf

    /**
     * <p>Assert that this class is sub-class of the given class. Any existing
     * statements for <code>subClassOf</code> will be removed.</p>
     * @param cls The class that this class is a sub-class of
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public void setSuperClass( Resource cls ) {
        setPropertyValue( getProfile().SUB_CLASS_OF(), "SUB_CLASS_OF", cls );
    }

    /**
     * <p>Add a super-class of this class.</p>
     * @param cls A class that is a super-class of this class.
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public void addSuperClass( Resource cls ) {
        addPropertyValue( getProfile().SUB_CLASS_OF(), "SUB_CLASS_OF", cls );
    }

    /**
     * <p>Answer a class that is the super-class of this class. If there is
     * more than one such class, an arbitrary selection is made.</p>
     * @return A super-class of this class
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public OntClass getSuperClass() {
        return (OntClass) objectAs( getProfile().SUB_CLASS_OF(), "SUB_CLASS_OF", OntClass.class );
    }

    /**
     * <p>Answer an iterator over all of the classes that are declared to be super-classes of
     * this class. Each element of the iterator will be an {@link OntClass}.</p>
     * @return An iterator over the super-classes of this class.
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public ExtendedIterator listSuperClasses() {
        return listSuperClasses( false );
    }

    /**
     * <p>Answer an iterator over all of the classes that are declared to be super-classes of
     * this class. Each element of the iterator will be an {@link OntClass}.
     * See {@link #listSubClasses( boolean )} for a full explanation of the <em>direct</em>
     * parameter.
     * </p>
     *
     * @param direct If true, only answer the direcly adjacent classes in the
     * super-class relation: i&#046;e&#046; eliminate any class for which there is a longer route
     * to reach that child under the super-class relation.
     * @return an iterator over the resources representing this class's sub-classes.
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public ExtendedIterator listSuperClasses( boolean direct ) {
        return UniqueExtendedIterator.create(
                listDirectPropertyValues( getProfile().SUB_CLASS_OF(), "SUB_CLASS_OF", OntClass.class, getProfile().SUB_CLASS_OF(), direct, false )
                .filterDrop( new SingleEqualityFilter( this ) ) );
    }

    /**
     * <p>Answer true if the given class is a super-class of this class.</p>
     * @param cls A class to test.
     * @return True if the given class is a super-class of this class.
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public boolean hasSuperClass( Resource cls ) {
        return hasSuperClass( cls, false );
    }

    /**
     * <p>Answer true if this class has any super-class in the model. Note that
     * when using a reasoner, all OWL classes have owl:Thing as a super-class.</p>
     * @return True if this class has any known super-class.
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public boolean hasSuperClass() {
        return getSuperClass() != null;
    }

    /**
     * <p>Answer true if the given class is a super-class of this class.
     * See {@link #listSubClasses( boolean )} for a full explanation of the <em>direct</em>
     * parameter.
     * </p>
     * @param cls A class to test.
     * @param direct If true, only search the classes that are directly adjacent to this
     * class in the class hierarchy.
     * @return True if the given class is a super-class of this class.
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public boolean hasSuperClass( Resource cls, boolean direct ) {
        if (!direct) {
            // don't need any special case, we just get the property
            return hasPropertyValue( getProfile().SUB_CLASS_OF(), "SUB_CLASS_OF", cls );
        }
        else {
            // we want the direct, not general relationship
            // first try to find an inf graph that can do the work for us
            InfGraph ig = null;
            if (getGraph() instanceof InfGraph) {
                ig = (InfGraph) getGraph();
            }
            else if (getGraph() instanceof OntModel) {
                OntModel m = (OntModel) getGraph();
                if (m.getGraph() instanceof InfGraph) {
                    ig = (InfGraph) m.getGraph();
                }
            }

            if (ig != null && ig.getReasoner().supportsProperty( ReasonerVocabulary.directSubClassOf )) {
                // we can look this up directly
                return hasPropertyValue( ReasonerVocabulary.directSubClassOf, "direct sub-class", cls );
            }
            else {
                // otherwise, not an inf-graph or the given inf-graph does not support direct directly (:-)
                return hasSuperClassDirect(cls);
            }
        }
    }

    /**
     * <p>Remove the given class from the super-classes of this class.  If this statement
     * is not true of the current model, nothing happens.</p>
     * @param cls A class to be removed from the super-classes of this class
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} class is not supported in the current language profile.
     */
    public void removeSuperClass( Resource cls ) {
        removePropertyValue( getProfile().SUB_CLASS_OF(), "SUB_CLASS_OF", cls );
    }

    /**
     * <p>Assert that this class is super-class of the given class. Any existing
     * statements for <code>subClassOf</code> on <code>prop</code> will be removed.</p>
     * @param cls The class that is a sub-class of this class
     * @exception OntProfileException If the {@link Profile#SUB_CLASS_OF()} property is not supported in the current language profile.
     */
    public void setSubClass( Resource cls ) {
        // first we have to remove all of the inverse sub-class links
        checkProfile( getProfile().SUB_CLASS_OF(), "SUB_CLASS_OF" );