如何获得具有相同对象属性断言的OWLIndividual集？

Question

我有一个本体，使用Protegé4.3.0创建，我将使用推理器来检索具有相同对象属性断言的OWLIndividual个体。

我读过this Q&A，但我想我应该修改建议的解决方案，因为我的问题略有不同，如下所述。

• 本体论包含一组个体(老鼠、猫、狗)，它们代表着某种动物。
• 本体包含一组个体(mouseEyes、mouseEars、mouseLegs、catEyes、catEars、catLegs、dogEyes、dogEars、dogLegs)，它们与不同的类(眼睛、耳朵、腿)相关联。

- The individuals _mouseEyes_, _catEyes_ and _dogEyes_ are associated to the class _Eyes_.
- The individuals _mouseEars_, _catEars_ and _dogEars_ are associated to the class _Ears_.
- The individuals _mouseLegs_, _catLegs_ and _dogLegs_ are associated to the class _Legs_.

​

• 例如，单个catEyes具有object属性断言arePartOf，该断言与catEyes和Cat关联。其他个体之间的关系与此类似。

给定mouseEyes、mouseEars、mouseLegs、catEyes、catEars、catLegs、dogEyes、dogEars、dogLegs中的指定个体，我将检索具有相同对象属性断言的个体集。例如，如果指定的个体是catEyes，那么推理者应该检索catEyes、catEars、catLegs。

我怎么能用推理者来完成这件事？

Answer 1

我发现getObjectPropertyValues中的OWLReasoner方法对于使用推理器解决问题中暴露的问题很有用。正如this comment中所指出的，SPARQL确实是查询模型的更好方法。

下面是我使用reasoner实现的解决方案。

import java.io.File;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import java.util.TreeSet;

import org.semanticweb.owlapi.apibinding.OWLManager;
import org.semanticweb.owlapi.model.IRI;
import org.semanticweb.owlapi.model.OWLClass;
import org.semanticweb.owlapi.model.OWLDataFactory;
import org.semanticweb.owlapi.model.OWLIndividual;
import org.semanticweb.owlapi.model.OWLNamedIndividual;
import org.semanticweb.owlapi.model.OWLObjectPropertyExpression;
import org.semanticweb.owlapi.model.OWLOntology;
import org.semanticweb.owlapi.model.OWLOntologyCreationException;
import org.semanticweb.owlapi.model.OWLOntologyID;
import org.semanticweb.owlapi.model.OWLOntologyManager;
import org.semanticweb.owlapi.model.PrefixManager;
import org.semanticweb.owlapi.reasoner.InferenceType;
import org.semanticweb.owlapi.reasoner.OWLReasoner;
import org.semanticweb.owlapi.reasoner.OWLReasonerFactory;
import org.semanticweb.owlapi.reasoner.structural.StructuralReasonerFactory;
import org.semanticweb.owlapi.util.DefaultPrefixManager;


public class Fauna {
    private final static OWLOntologyManager manager = OWLManager.createOWLOntologyManager();
    private final static OWLDataFactory df = manager.getOWLDataFactory();
    private final static OWLReasonerFactory rf = new StructuralReasonerFactory();

    private final OWLOntology ontology;
    private final OWLOntologyID id;
    private final IRI iri;
    private final PrefixManager pm;

    private final OWLReasoner reasoner;

    private final OWLObjectPropertyExpression arePartsOf;
    private final TreeSet<OWLClass> clsParts = new TreeSet<>();

    /**
     * 
     * @param file
     * @throws OWLOntologyCreationException
     */
    public Fauna(File file) throws OWLOntologyCreationException {
        ontology = manager.loadOntologyFromOntologyDocument(file);
        id = ontology.getOntologyID();
        iri = id.getOntologyIRI();
        pm = new DefaultPrefixManager(iri.toString().concat("#"));

        reasoner = rf.createReasoner(ontology);
        reasoner.precomputeInferences(InferenceType.OBJECT_PROPERTY_ASSERTIONS);

        arePartsOf = df.getOWLObjectProperty(IRI.create(iri + "#arePartsOf"));

        for (String s : new String[] { "Eyes", "Ears", "Legs" }) {
            OWLClass cls = df.getOWLClass(":" + s, pm);
            clsParts.add(cls);
        }
    }

    /**
     * 
     * @param individual
     * @return
     */
    private Set<OWLNamedIndividual> getPartsOfSameSpecies(OWLNamedIndividual individual) {
        if (!ontology.containsIndividualInSignature(individual.getIRI())) {
            return null;
        }

        Set<OWLClass> types = reasoner.getTypes(individual, true).getFlattened();
        if (Collections.disjoint(clsParts, types)) {
            return null;
        }

        Set<OWLNamedIndividual> values = reasoner.getObjectPropertyValues(individual, arePartsOf).getFlattened();
        if (values == null || values.size() != 1) {
            return null;
        }

        OWLNamedIndividual species = values.iterator().next();
        return this.getParts(species);
    }

    /**
     * 
     * @param species
     * @return
     */
    public Set<OWLNamedIndividual> getParts(OWLNamedIndividual species) {
        HashSet<OWLNamedIndividual> individuals = new HashSet<>();

        for (OWLClass cls : clsParts) {
            for (OWLIndividual i : cls.getIndividuals(ontology)) {
                OWLNamedIndividual part = i.asOWLNamedIndividual();

                if (!reasoner.getObjectPropertyValues(part, arePartsOf).containsEntity(species)) {
                    continue;
                }

                individuals.add(part);
            }
        }

        return individuals;
    }
}