Ignoring DTD in XMLUnit

@BeforeClass
public static void onlyOnce() {

 XMLUnit.setIgnoreWhitespace(true);
 XMLUnit.setIgnoreComments(true);
 XMLUnit.setIgnoreAttributeOrder(true);

 // don't validate dtd
 DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
 dbf.setValidating(false);
 try {
   dbf.setFeature("http://xml.org/sax/features/namespaces", false);
   dbf.setFeature("http://xml.org/sax/features/validation", false);
   dbf.setFeature(
       "http://apache.org/xml/features/nonvalidating/load-dtd-grammar",
       false);
   dbf.setFeature(
       "http://apache.org/xml/features/nonvalidating/load-external-dtd",
       false);
 } catch (ParserConfigurationException e) {
   e.printStackTrace();
 }

 XMLUnit.setTestDocumentBuilderFactory(dbf);
 XMLUnit.setControlDocumentBuilderFactory(dbf);
}