如何在猫头鹰API中获得个人类别

Question

如何与推理者一起让猫头鹰的个人班级

        OWLOntologyManager manager = OWLManager.createOWLOntologyManager();
        OWLOntology ontology = manager.loadOntologyFromOntologyDocument(new StringDocumentSource(KOALA));

        IRI ontologyIRI = IRI.create("http://www.semanticweb.org/xxxxx/ontologies/2017/10/ontology");
        OWLDataFactory factory = manager.getOWLDataFactory();
        OWLIndividual john = factory.getOWLNamedIndividual(IRI.create(ontologyIRI + "#John"));
        OWLDataPropertyExpression hasConnexion= factory.getOWLDataProperty(IRI.create(ontologyIRI + "#hasConnexion"));
        OWLDataPropertyAssertionAxiom axiom = factory.getOWLDataPropertyAssertionAxiom(hasConnexion, john, 3);
        AddAxiom addAxiom = new AddAxiom(ontology, axiom);
        manager.applyChange(addAxiom);
        manager.saveOntology(ontology, new StreamDocumentTarget(System.out));

        //reasoner
        OWLReasonerFactory reasonerFactory = new StructuralReasonerFactory();
        OWLReasoner reasoner = reasonerFactory.createReasoner(ontology);

        OWLClass myClass= fac.getOWLClass(IRI.create("http://www.semanticweb.org/xxxxx/ontologies/2017/10/ontology#hasConnexion"));

        NodeSet<OWLNamedIndividual> individuals = reasoner.getInstances(myClass,
                false);
         for (Node<OWLNamedIndividual> i : individuals)
         {
             System.out.println(i.getClass());
         }

我希望结果是每个人的班级但是推理者没有结果。在Protege中，它的工作效果很好，但是当我使用本体学并尝试与OWL API合作时，我没有任何结果

Answer 1

是的，这是行不通的。i.getClass()将为您提供Java类，而不是个人的主张类型。要获得所需的主张类型，您需要调用ontology.axioms(i).collect(Collectors.toSet())。这只会返回已添加到本体的断言。

要获得推断的类型，您需要致电reasoner.types(i).collect(Collectors.toSet())。

让我感到困扰的是，您说您有 no 结果。我希望您应该得到很多错误的结果（即Java课程，而不是OWL课程）。好的，因此您正在代码段中创建一个本体。您没有得到任何结果的原因是您尚未为john添加类主张公理。您需要添加一个factory.getOWLClassAssertionAxiom(owlClassExpression, john)，其中owlClassExpression代表您本体中的类，例如Person。

Answer 2

基于猫头鹰API示例，这是两个示例：

获得猫头鹰风格的子类：

OWLOntologyManager owlManager OWLManager.createOWLOntologyManager();
IRI iri = IRI.create("http://www.semanticweb.org/music-ontology#Style");
OWLClass style = owlManager.getOWLDataFactory().getOWLClass(iri);
OWLReasonerFactory reasonerFactory = new StructuralReasonerFactory();
OWLReasoner reasoner = reasonerFactory.createReasoner(ontologia);
NodeSet<OWLClass> subClasses = reasoner.getSubClasses(style, true);
Set<OWLClass> clses = subClasses.getFlattened();
Log.d(TAG, "Subclasses of Style: ");
for (OWLClass cls : clses) {
    String s = cls.toString();
    Log.d(TAG, s.substring(s.indexOf("#") + 1, s.length() -1));
}

获得猫头鹰岩石的个人：

OWLOntologyManager owlManager OWLManager.createOWLOntologyManager();
IRI iri = IRI.create("http://www.semanticweb.org/music-ontology#Rock");
OWLClass rock = owlManager.getOWLDataFactory().getOWLClass(iri);
OWLReasonerFactory reasonerFactory = new StructuralReasonerFactory();
OWLReasoner reasoner = reasonerFactory.createReasoner(ontologia);
NodeSet<OWLNamedIndividual> individualsNodeSet = reasoner.getInstances(rock, true);
Set<OWLNamedIndividual> individuals = individualsNodeSet.getFlattened();
Log.d(TAG, "Instances of Rock: ");
for (OWLNamedIndividual ind : individuals) {
    String s = ind.toString();
    Log.d(TAG, s.substring(s.indexOf("#") + 1, s.length() -1));
}