Java owlapi 提取物

Question

I have an ontology

<owl:ObjectProperty rdf:about="http://purl.obolibrary.org/obo/BFO_0000050">
    <owl:inverseOf rdf:resource="http://purl.obolibrary.org/obo/BFO_0000051"/>
    <rdf:type rdf:resource="http://www.w3.org/2002/07/owl#TransitiveProperty"/>
    <oboInOwl:hasDbXref rdf:datatype="http://www.w3.org/2001/XMLSchema#string">BFO:0000050</oboInOwl:hasDbXref>
    <oboInOwl:hasOBONamespace rdf:datatype="http://www.w3.org/2001/XMLSchema#string">external</oboInOwl:hasOBONamespace>
    <oboInOwl:id rdf:datatype="http://www.w3.org/2001/XMLSchema#string">part_of</oboInOwl:id>
    <oboInOwl:shorthand rdf:datatype="http://www.w3.org/2001/XMLSchema#string">part_of</oboInOwl:shorthand>
    <rdfs:label rdf:datatype="http://www.w3.org/2001/XMLSchema#string">part of</rdfs:label>
</owl:ObjectProperty>

I'm trying to extract all the ObjectProperties,

for (OWLObjectProperty obp : ont.getObjectPropertiesInSignature()){
    System.out.println(obp.toString());
}

this will print the name of ObjectProperty, eg http://purl.obolibrary.org/obo/BFO_0000050 .

I wonder how to get the rdfs:label, eg part of

Answer 1

The rdfs:label in OWL is an annotation . To get the label you must query for the annotation of the objectProperty you want.

To display all annotations of an ontology you can do something like that :

final OWLOntology ontology = manager.loadOntologyFromOntologyDocument(new File(my_file));

final List<OWLAnnotation> annotations = ontology.objectPropertiesInSignature()//
    .filter(objectProperty -> objectProperty.equals(the_object_property_I_want))//
    .flatMap(objectProperty -> ontology.annotationAssertionAxioms(objectProperty.getIRI()))//
    .map(OWLAnnotationAssertionAxiom::getAnnotation)//
    .collect(Collectors.toList());

for (final OWLAnnotation annotation : annotations)
    System.out.println(annotation.getProperty() + "\t" + annotation.getValue());

getObjectPropertiesInSignature() is deprecated in the modern (more than one year) version of owlapi (5). So please considere using the stream version objectPropertiesInSignature of java-8 . java-9 have been release few days ago, so it is a good time to learn the stream functionnality.

NB: the annotations are almost free, but OWL2 have put some more standardisation on it, so there is annotations with 'predefined semantics'.