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我正在尝试使用 Jena API 创建一个本体，输出将在 OWL 中粘贴下来。

import com.hp.hpl.jena.ontology.Individual;
import com.hp.hpl.jena.ontology.ObjectProperty;
import com.hp.hpl.jena.ontology.OntClass;
import com.hp.hpl.jena.ontology.OntModel;
import com.hp.hpl.jena.rdf.model.ModelFactory;

public class BandsOntology {

    public static void main(String[] args) 
    {
        // Create an empty ontology model
        OntModel m = ModelFactory.createOntologyModel();
        String baseURI = "http://www.bands.fr";
        String NSBand = baseURI + "#";

        m.setNsPrefix("Band", NSBand);

        OntClass Band = m.createClass(NSBand + "Band");
        OntClass Guitarist = m.createClass(NSBand + "Guitarist");
        OntClass Bassist = m.createClass(NSBand + "Bassist");
        OntClass Keyboardist = m.createClass(NSBand + "Keyboardist");
        OntClass Vocalist  = m.createClass(NSBand + "Vocalist ");

        ObjectProperty bandComposedBy = m.createObjectProperty(NSBand +"composedBy");
        bandComposedBy.hasDomain(Band);
        bandComposedBy.hasRange(Guitarist);
        bandComposedBy.hasRange(Bassist);
        bandComposedBy.hasRange(Keyboardist);       
        bandComposedBy.hasRange(Vocalist);      

        Individual queen = Band.createIndividual(NSBand + "Queen");
        Individual guitarist01 = Guitarist.createIndividual(NSBand + "guita01");        

        m.add(queen, bandComposedBy, guitarist01);

        m.write(System.out, Constants.TYPE_RDF_XML_ABBREV);

    }

}

控制台上的输出：

<rdf:RDF
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:Band="http://www.bands.fr#"
    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="http://www.bands.fr#Bassist"/>
  <owl:Class rdf:about="http://www.bands.fr#Band"/>
  <owl:Class rdf:about="http://www.bands.fr#Vocalist "/>
  <owl:Class rdf:about="http://www.bands.fr#Keyboardist"/>
  <owl:Class rdf:about="http://www.bands.fr#Guitarist"/>
  <owl:ObjectProperty rdf:about="http://www.bands.fr#composedBy"/>
  <Band:Band rdf:about="http://www.bands.fr#Queen">
    <Band:composedBy>
      <Band:Guitarist rdf:about="http://www.bands.fr#guita01"/>
    </Band:composedBy>
  </Band:Band>
</rdf:RDF>

我在问为什么在声明该属性后，我没有在我编码时声明“composedBy”属性。

<owl:ObjectProperty rdf:about="http://www.bands.fr#composedBy">
    <rdfs:domain rdf:resource="http://www.bands.fr#Band"/>
    <rdfs:range rdf:resource="http://www.bands.fr#Bassist"/>
    <rdfs:range rdf:resource="http://www.bands.fr#Guitarist"/>
    ...
</owl:ObjectProperty>
4

1 回答 1

1

hasDomain和hasRange不添加域和范围，如果属性具有指定的域和范围，它们只会返回 true。这些方法的 Javadoc 对此进行了解释，并遵循 Java 中的典型命名约定，即如果对象满足某些条件，则以 has- 或 is- 开头的方法返回 true。

您应该改用addDomain和addRange。也就是说，而不是

bandComposedBy.hasDomain(Band);
bandComposedBy.hasRange(Guitarist);
bandComposedBy.hasRange(Bassist);
bandComposedBy.hasRange(Keyboardist);       
bandComposedBy.hasRange(Vocalist);

你应该使用：

bandComposedBy.addDomain(Band);
bandComposedBy.addRange(Guitarist);
bandComposedBy.addRange(Bassist);
bandComposedBy.addRange(Keyboardist);       
bandComposedBy.addRange(Vocalist);
于 2014-03-14T15:57:26.637 回答