Namespace lost when transforming using Xalan

Question

Hi Java experts,
I'm trying to output a DOM object to a file. I used Xerces to create the DOM object:
     DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
     factory.setNamespaceAware(true);
     DocumentBuilder docBuilder = factory.newDocumentBuilder();
     docBuilder.setErrorHandler(new MyErrorHandler());
     this.userPrefsDocument = docBuilder.newDocument();
     this.userPrefsRootNode = this.userPrefsDocument.getDocumentElement();
     if (this.userPrefsRootNode == null) {
          this.userPrefsRootNode = this.userPrefsDocument.createElementNS(
               ROOTNAMESPACE, "ROOT");
          this.userPrefsDocument.appendChild(this.userPrefsRootNode);
     System.out.println(this.userPrefsRootNode.getNamespaceURI());
When I do this, the namespace is printed out (the same as ROOTNAMESPACE). Now, when I transform this using the following, the namespace is all lost in the output XML file:
     TransformerFactory factory = TransformerFactory.newInstance();
     Transformer transformer = factory.newTransformer();
     DOMSource source = new DOMSource(this.userPrefsDocument);
     StreamResult result = new StreamResult(SETTINGSLOCATION);
     transformer.transform(source, result);
What I get is the following:
<?xml version="1.0" encoding="UTF-8"?>
<ROOT/>
What I want to get is the following:
<?xml version="1.0" encoding="UTF-8"?>
<ROOT xmlns="http://www.blahblah.com/"/>
I know I could easily resolve this with a:
     this.userPrefsRootNode.setAttribute("xmlns", ROOTNAMESPACE);
but, since I'm setting the namespace on the root element, and enabling namespace for the parser, I thought this would kind of "automagically" get included when performing a transform(). Or, is this what everyone does to enable namespacing in XML? Thanks in advance!

Answer 1

OK, this is what I tried:
          try {
               DocumentBuilderFactory factory = DocumentBuilderFactory
                         .newInstance();
               factory.setNamespaceAware(true);
               DocumentBuilder docBuilder = factory.newDocumentBuilder();
               Document doc = docBuilder.newDocument();
               Element root = doc.getDocumentElement();
               root = doc.createElementNS("http://www.abcdefg.com",
                         "myapp:ROOT");
               doc.appendChild(root);
               System.out.println(root.getNamespaceURI());
               TransformerFactory tFactory = TransformerFactory.newInstance();
               Transformer transformer = tFactory.newTransformer();
               DOMSource source = new DOMSource(doc);
               StreamResult result = new StreamResult(new File(System
                         .getProperty("user.home")
                         + "/.myapp.xml"));
               transformer.transform(source, result);
          } catch (Exception e) {
               e.printStackTrace();
The result I get is:
<?xml version="1.0" encoding="UTF-8"?>
<myapp:ROOT/>
Which is still not what I'm really looking for... I guess it's just easier to move to dom4j rather than wrestling around with DOM :P