After making the change suggested above by Martin, I was still getting the same error. I had to make an additional change to my parsing code. I was parsing the XML file via a DocumentBuilder as shown in the oracle docs: https://docs.oracle.com/javase/7/docs/api/javax/xml/validation/package-summary.html
// parse an XML document into a DOM tree
DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document document = parser.parse(new File("example.xml"));
The problem was that DocumentBuilder is not namespace aware by default. The following additional change resolved the issue:
// parse an XML document into a DOM tree
DocumentBuilderFactory dmfactory = DocumentBuilderFactory.newInstance();
dmfactory.setNamespaceAware(true);
DocumentBuilder parser = dmfactory.newDocumentBuilder();
Document document = parser.parse(new File("example.xml"));