Question

我打算使用Jena API为类添加对象属性。

我找不到如何做到这一点的正确方法。我想实现类似于Protege中可以做的事情： ObjectProperty in Protege

ExampleObjectProperty是我自己的ObjectProperty。

我尝试使用ontClass.addProperty添加此属性，同时向ontModel添加新语句，但结果不一样。

据我所知，在Protege中，生成了空白节点（说明：blank_node有一些onProperty ExampleObjectProperty，而ExampleClass有someValuesOf：blank_node ......虽然我不确定）。

Answer 1

loopasam's comment是正确的;你不是想“为一个类添加一个属性”或类似的东西。你要做的是添加一个子类公理。在曼彻斯特OWL语法中，它看起来或多或少像：

ExampleResource subClassOf （ExampleObjectProperty some ExampleClass）

Jena的OntModel API使得创建这种公理变得非常容易。这是你如何做到的：

import com.hp.hpl.jena.ontology.OntClass;
import com.hp.hpl.jena.ontology.OntModel;
import com.hp.hpl.jena.ontology.OntModelSpec;
import com.hp.hpl.jena.ontology.OntProperty;
import com.hp.hpl.jena.rdf.model.ModelFactory;

public class SubclassOfRestriction {
    public static void main(String[] args) {
        final String NS = "https://stackoverflow.com/q/20476826/";
        final OntModel model = ModelFactory.createOntologyModel( OntModelSpec.OWL_DL_MEM );

        // Create the two classes and the property that we'll use.
        final OntClass ec = model.createClass( NS+"ExampleClass" );
        final OntClass er = model.createClass( NS+"ExampleResource" );
        final OntProperty eop = model.createOntProperty( NS+"ExampleObjectProperty" );

        // addSuperClass and createSomeValuesFromRestriction should be pretty straight-
        // forward, especially if you look at the argument names in the Javadoc.  The 
        // null just indicates that the restriction class will be anonymous;  it doesn't
        // have an URI of its own.  
        er.addSuperClass( model.createSomeValuesFromRestriction( null, eop, ec ));

        // Write the model. 
        model.write( System.out, "RDF/XML-ABBREV" );
        model.write( System.out, "TTL" );
    }
}

输出结果为：

<rdf:RDF
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:owl="http://www.w3.org/2002/07/owl#"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
    xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#">
  <owl:Class rdf:about="https://stackoverflow.com/q/20476826/ExampleResource">
    <rdfs:subClassOf>
      <owl:Restriction>
        <owl:someValuesFrom>
          <owl:Class rdf:about="https://stackoverflow.com/q/20476826/ExampleClass"/>
        </owl:someValuesFrom>
        <owl:onProperty>
          <rdf:Property rdf:about="https://stackoverflow.com/q/20476826/ExampleObjectProperty"/>
        </owl:onProperty>
      </owl:Restriction>
    </rdfs:subClassOf>
  </owl:Class>
</rdf:RDF>

@prefix rdfs:  <http://www.w3.org/2000/01/rdf-schema#> .
@prefix owl:   <http://www.w3.org/2002/07/owl#> .
@prefix xsd:   <http://www.w3.org/2001/XMLSchema#> .
@prefix rdf:   <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

<https://stackoverflow.com/q/20476826/ExampleObjectProperty>
        a       rdf:Property .

<https://stackoverflow.com/q/20476826/ExampleClass>
        a       owl:Class .

<https://stackoverflow.com/q/20476826/ExampleResource>
        a                owl:Class ;
        rdfs:subClassOf  [ a                   owl:Restriction ;
                           owl:onProperty      <https://stackoverflow.com/q/20476826/ExampleObjectProperty> ;
                           owl:someValuesFrom  <https://stackoverflow.com/q/20476826/ExampleClass>
                         ] .

在Protégé中，如下所示：

Protégé screenshot similar to OP's ]。

使用Jena API为Ontclass添加ObjectPropety

1 个答案: