code: public Node replaceChild(Node newChild, Node oldChild) throws DOMException
    {
  
      error(XMLErrorResources.ER_FUNCTION_NOT_SUPPORTED);  //"replaceChild not supported!");
  
      return null;
    }
docs: Unimplemented. See org.w3c.dom.Node
  
  @param newChild Replace existing child with this one
  @param oldChild Existing child to be replaced
  
  @return null
  
  @throws DOMException