如何创建OWL文档

Question

我已经从网上下载了一个OWL文件，我需要知道它是如何使用Jena编写的。我可以写简单的RDF文档，但我不明白要编写OWL文档。 OWL文件内容如下。

<rdf:RDF 
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
    xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#" 
    xmlns:owl="http://www.w3.org/2002/07/owl#" 
    xmlns:dc="http://purl.org/dc/elements/1.1/"> 

    <!-- OWL Header Example --> 
    <owl:Ontology rdf:about="http://www.linkeddatatools.com/plants"> 
     <dc:title>The LinkedDataTools.com Example Plant Ontology</dc:title> 
     <dc:description>An example ontology written for the LinkedDataTools.com RDFS & OWL introduction tutorial</dc:description> 
    </owl:Ontology> 

    <!-- OWL Class Definition Example --> 
    <owl:Class rdf:about="http://www.linkeddatatools.com/plants#planttype"> 
     <rdfs:label>The plant type</rdfs:label> 
     <rdfs:comment>The class of plant types.</rdfs:comment> 
     <rdfs:description> Plant type description </rdfs:description> 
    </owl:Class> 
</rdf:RDF> 

Answer 1

没有区别。以RDF编码的OWL本体只是另一个RDF文档 - 就Jena而言，OWL语法没有特别之处。 RDF文档中的重要性在于其包含的三元组：这就是为什么您可以使用XML，海龟或N三元组编码RDF，并且它们都是等价的 - 只是写下相同三元组的不同方式。

一旦RDF工具将三元组加载到图形中（即Jena中的Model），则它可以对来自owl:名称空间的术语给出不同的解释。

更新

OK，在这里评论以下请求的代码生成的输出样本：

package example; 

import com.hp.hpl.jena.ontology.*; 
import com.hp.hpl.jena.rdf.model.ModelFactory; 
import com.hp.hpl.jena.vocabulary.*; 

public class OWLOutputExample 
{ 
    public static final String PLANTS = "http://www.linkeddatatools.com/plants"; 

    public static void main(String[] args) { 
     new OWLOutputExample().run(); 
    } 

    public void run() { 
     OntModel m = ModelFactory.createOntologyModel(OntModelSpec.OWL_MEM); 

     setNamespaces(m); 
     populateOntology(m); 
     writeOntology(m); 
    } 

    private void setNamespaces(OntModel m) { 
     m.setNsPrefix("owl", OWL.getURI()); 
     m.setNsPrefix("rdf", RDF.getURI()); 
     m.setNsPrefix("rdfs", RDFS.getURI()); 
     m.setNsPrefix("dc", DC_11.getURI()); 
     m.setNsPrefix("plants", PLANTS); 
    } 

    private void populateOntology(OntModel m) { 
     Ontology ont = m.createOntology(PLANTS); 
     ont.addProperty(DC_11.title, "The LinkedDataTools.com Example Plant Ontology") 
      .addProperty(DC_11.description, "An example ontology written for the " + 
               "LinkedDataTools.com RDFS & OWL introduction tutorial"); 

     OntClass plantType = m.createClass(PLANTS + "#planttype"); 
     plantType.addProperty(RDFS.label, "The plant type") 
       .addProperty(RDFS.comment, "The class of plant types."); 
    } 

    private void writeOntology(OntModel m) { 
     m.write(System.out, "RDF/XML-ABBREV"); 
    } 
} 

输出：

<rdf:RDF 
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
    xmlns:plants="http://www.linkeddatatools.com/plants" 
    xmlns:owl="http://www.w3.org/2002/07/owl#" 
    xmlns:dc="http://purl.org/dc/elements/1.1/" 
    xmlns:xsd="http://www.w3.org/2001/XMLSchema#" 
    xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"> 
    <owl:Ontology rdf:about="http://www.linkeddatatools.com/plants"> 
    <dc:description>An example ontology written for the LinkedDataTools.com RDFS &amp; OWL introduction tutorial</dc:description> 
    <dc:title>The LinkedDataTools.com Example Plant Ontology</dc:title> 
    </owl:Ontology> 
    <owl:Class rdf:about="http://www.linkeddatatools.com/plants#planttype"> 
    <rdfs:comment>The class of plant types.</rdfs:comment> 
    <rdfs:label>The plant type</rdfs:label> 
    </owl:Class> 
</rdf:RDF> 

注意rdfs:description不是已知RDFS属性，所以我把它排除了。