Node searching with Xerces

[Shashank Agarwal]

I'm trying to find a node in my XML document, but it should be within a specific parent. Here's what the XML looks like -

<article>
  <sec>
    <title>Methods</title>
    <sec>
      <title>Western blotting</title>
    </sec>
  </sec>
</article>

Here, "Methods" is the main title, but "Western Blotting" is the subtitle. If I just want to capture the titles, then I'd want to look for "article/sec/title", but if I want only subtitles, I'd look for "articles/sec/sec/title". I'm using xerces. Here's what I've got -

DOMParser parser = new DOMParser();
 
parser.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);
 
parser.parse(article);
            
Document doc = parser.getDocument();
Element root = doc.getDocumentElement();
NodeList nl = doc.getElementsByTagName("title");
 

But this gets all the titles (including sub-titles). I tried replacing "title" with "article/sec/title" and "article::sec::title", but that just returns no nodes. Searched online, but didn't find anything.

[Yves Zoundi]

Have a look at the package javax.xml.xpath

[Shashank Agarwal]

Thanks Yves!!! It worked.

Just for anyone who has the same problem in future, here's the code that I used -

XPathFactory xPathFactory = XPathFactory.newInstance();
XPath xPath = xPathFactory.newXPath();
XPathExpression titles = xPath.compile("//article/sec/title");
            
DOMParser parser = new DOMParser();
 
parser.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);
 
parser.parse(article);
            
Document doc = parser.getDocument();
NodeList nodes = (NodeList) titles.evaluate(doc, XPathConstants.NODESET);
            
for (int i = 0; i < nodes.getLength(); ++i) {
  System.out.println(nodes.item(i).getTextContent());
}
 

Found the code off http://www.ibm.com/developerworks/library/x-javaxpathapi.html