相关疑难解决方法(0)

我有一个XML文件形式的OWL文档.我想从这个文档中提取元素.我的代码适用于简单的XML文档,但它不适用于OWL XML文档.

我实际上是想获得这个元素:/rdf:RDF/owl:Ontology/rdfs:label为此我做了这个:

 DocumentBuilder builder = builderfactory.newDocumentBuilder();
    Document xmlDocument = builder.parse(
            new File(XpathMain.class.getResource("person.xml").getFile()));

    XPathFactory factory = javax.xml.xpath.XPathFactory.newInstance();
    XPath xPath = factory.newXPath();
    XPathExpression xPathExpression = xPath.compile("/rdf:RDF/owl:Ontology/rdfs:label/text()");
    String nameOfTheBook = xPathExpression.evaluate(xmlDocument,XPathConstants.STRING).toString();

我也试过这样只提取rdfs:label元素:

 XPathExpression xPathExpression = xPath.compile("//rdfs:label");        
 NodeList nodes = (NodeList) xPathExpression.evaluate(xmlDocument, XPathConstants.NODESET);

但是这个节点列表是空的.

请让我知道我哪里出错了.我正在使用Java XPath API.