使用OWL API，给定一个OWLClass，我如何获得它的<rdfs：label>？</rdfs：label>

Question

使用OWL API 3.4.9。

鉴于OWLClass和本体，如何在该本体中获得<rdfs:label>的{​​{1}}？

我希望获得OWLClass类型的标签。

Answer 1

受guide to the OWL-API的启发，以下代码应该有效（未经过测试）：

//Initialise
OWLOntologyManager m = create();
OWLOntology o = m.loadOntologyFromOntologyDocument(pizza_iri);
OWLDataFactory df = OWLManager.getOWLDataFactory();

//Get your class of interest
OWLClass cls = df.getOWLClass(IRI.create(pizza_iri + "#foo"));

// Get the annotations on the class that use the label property (rdfs:label)
for (OWLAnnotation annotation : cls.getAnnotations(o, df.getRDFSLabel())) {
  if (annotation.getValue() instanceof OWLLiteral) {
    OWLLiteral val = (OWLLiteral) annotation.getValue();
    // look for portuguese labels - can be skipped
      if (val.hasLang("pt")) {
        //Get your String here
        System.out.println(cls + " labelled " + val.getLiteral());
      }
   }
}

Answer 2

accepted answer对OWLAPI版本3.x（3.4和3.5版本）有效，但对OWL-API 4.x及更新版本无效。

要检索针对OWL类声明的rdfs:label值，请尝试以下方法：

OWLClass c = ...; 
OWLOntology o = ...;
IRI cIRI = c.getIRI();
for(OWLAnnotationAssertionAxiom a : ont.getAnnotationAssertionAxioms(cIRI)) {
    if(a.getProperty().isLabel()) {
        if(a.getValue() instanceof OWLLiteral) {
            OWLLiteral val = (OWLLiteral) a.getValue();
            System.out.println(c + " labelled " + val.getLiteral());
        }
    }
}

修改

正如Ignazio指出的那样，EntitySearcher也可以使用，例如：

OWLClass c = ...; 
OWLOntology o = ...;
for(OWLAnnotation a : EntitySearcher.getAnnotations(c, o, factory.getRDFSLabel())) {
    OWLAnnotationValue val = a.getValue();
    if(value instanceof OWLLiteral) {
        System.out.println(c + " labelled " + ((OWLLiteral) value).getLiteral());   
    }
}

Answer 3

这是我用来从类中提取标签的方法。

private List<String> classLabels(OWLClass class){
    List<String> labels;
    labels = ontologiaOWL.annotationAssertionAxioms(class.getIRI())
            //get only the annotations with rdf Label property
            .filter(axiom -> axiom.getProperty().getIRI().getIRIString().equals(OWLRDFVocabulary.RDFS_LABEL.getIRI().getIRIString()))
            .map(axiom -> axiom.getAnnotation())
            .filter(annotation-> annotation.getValue() instanceof OWLLiteral)
            .map(annotation -> (OWLLiteral) annotation.getValue())
            .map(literal -> literal.getLiteral())
            .collect(Collectors.toList());

     return labels;
}