Java XML Parse / Query

Question

I have such XML structure, when I use NodeList nList = doc.getElementsByTagName("stock"); it return me 3 stocks, 2 main stock tags and one which is under substocks. I want to get only two stock which is on upper level and ignore all which is under substock tags.

Is it possible in Java to make something like LINQ query in C#, say return me elements only where name is equals to "Sony".

Thanks!

<city>
   <stock>
     <name>Sony</name>
   </stock>
   <stock>
     <name>Panasonic</name>
     <substocks>
          <stock>
             <name>Panasonic Shop 2</name>
          </stock>
     </substocks>
   </stock>
</city>

Answer 1

I recommend you to use XPath with javax.xml.xpath package:

final InputStream is = new FileInputStream('your.xml');

final DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
final DocumentBuilder builder = factory.newDocumentBuilder();
final Document doc = builder.parse(is);
final XPathFactory xPathfactory = XPathFactory.newInstance();
final XPath xpath = xPathfactory.newXPath();
final XPathExpression expr = xpath.compile("/city/stock/name[text()='Sony']");

and then:

final NodeList nl = (NodeList) expr.evaluate(doc, XPathConstants.NODESET);

Answer 2

Take a look on XPath and its java implementation JXPath . Other possible approach is parsing XML using JAXB and operating objects list using LambdaJ.

Answer 3

There is also dom4j library which has powerful navigation with XPath:

import org.dom4j.Document;
import org.dom4j.io.SAXReader;

SAXReader reader = new SAXReader();
Document document = reader.read("test.xml");
List list = document.selectNodes("/city/stock/name[text()='Sony']");
for (Iterator iter = list.iterator(); iter.hasNext(); ) {
    // TODO: place you logic here
}

More examples are here

Answer 4

Try jcabi-xml (see this blog post ) with a one-liner:

Collection<XML> found = new XMLDocument("your document here").nodes(
  "/city/stock/name[text()='Sony']"
);