Parse XML contains incrementing namespace numbers and multiple namespaces - xpath

Question

Parse XML contains incrementing namespace numbers and multiple namespaces, this xml is a service which can't be updated. The original approach was to simply ummarshal it to the java objects and be on our way. The provider uses older tools Castor to create the message, which we have no access to. The plan is to parse it then marshal/unmarshal it.
<TESTXmlResponse xmlns="TEST/TESTXmlResponse">
<firstRequest>
<ns1:xmlRquest xmls:ns1="TEST/XMLRequest">
<ns2:username xmls:ns2="TEST/XMLUserNameRequest">
<ns3:value xmls:ns3=TEST/XMLValueRequest">test</ns3:value>
</ns2:username>
</ns1:xmlRquest>
</firstRequest>
<data>
<ns4:name xmls:ns4="TEST/XMLConstants">name1</ns4:name>
<ns5:value xmls:ns5=TEST/XMLConstants">data1</ns5:value>
</data>
<data>
<ns6:name xmls:ns6="TEST/XMLConstants">name2</ns6:name>
<ns7:value xmls:ns7=TEST/XMLConstants">data2</ns7:value>
</data>
<data>
<ns8:name xmls:ns8="TEST/XMLConstants">name3</ns8:name>
<ns9:value xmls:ns9=TEST/XMLConstants">data3/ns9:value>
</data>
</TESTXmlResponse>
import java.io.File;
import java.io.FileInputStream;
import java.util.ArrayList;
import java.util.Iterator;
import javax.xml.XMLConstants;
import javax.xml.namespace.NamespaceContext;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
public class Main
{
public static void main(String[] args) throws Exception
{
ArrayList<String> constants = new ArrayList<String>();
DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(new
FileInputStream(newfile("constants.xml")));
Get XPath expression
XPathFactory xpathfactory = XPathFactory.newInstance();
XPath xpath = xpathfactory.newXPath();
xpath.setNamespaceContext(new NamespaceResolver(doc));
XPathExpression expr =
xpath.compile("//firstRequest/ns1:xmlRequest/ns2:username/ns3:value/text()");
Object result = expr.evaluate(doc, XPathConstants.NODESET);
NodeList nodes = (NodeList) result;
for (int i = 0; i < nodes.getLength(); i++) {
constants.add(nodes.item(i).getNodeValue());
}
if (constants.size() > 0){
System.out.println(constants);
}
}
class NamespaceResolver implements NamespaceContext
{
private Document sourceDocument;
public NamespaceResolver(Document document) {
sourceDocument = document;
}
public String getNamespaceURI(String prefix) {
if (prefix.equals(XMLConstants.DEFAULT_NS_PREFIX)) {
return sourceDocument.lookupNamespaceURI(null);
} else {
return sourceDocument.lookupNamespaceURI(prefix);
}
}
public String getPrefix(String namespaceURI) {
return sourceDocument.lookupPrefix(namespaceURI);
}
#SuppressWarnings("rawtypes")
public Iterator getPrefixes(String namespaceURI) {
return null;
}
}
nodelist returned from the expr is where the issue lies, isn't null, but the length is zero 0.
I've looked at several examples, this one seems to be the closet to a solution. The XPathExpression expr appears to be the issue. Refining it for each case would seem to be a reasonable approach.