code: public void serializeDOM3(Node node) throws IOException {
          try {
              DOM3TreeWalker walker = new DOM3TreeWalker(fSerializationHandler,
                      fErrorHandler, fSerializerFilter, fNewLine);
  
              walker.traverse(node);
          } catch (org.xml.sax.SAXException se) {
              throw new WrappedRuntimeException(se);
          }
      }
docs: Serializes the Level 3 DOM node by creating an instance of DOM3TreeWalker
  which traverses the DOM tree and invokes handler events to serialize
  the DOM NOde. Throws an exception only if an I/O exception occured
  while serializing.
  This interface is a public API.
  
  @param node the Level 3 DOM node to serialize
  @throws IOException if an I/O exception occured while serializing