code: protected void isElementWellFormed(Node node) {
          boolean isNameWF = false;
          if ((fFeatures & NAMESPACES) != 0) {
              isNameWF =
                  isValidQName(
                      node.getPrefix(),
                      node.getLocalName(),
                      fIsXMLVersion11);
          } else {
              isNameWF = isXMLName(node.getNodeName(), fIsXMLVersion11);
          }
  
          if (!isNameWF) {
              String msg =
                  Utils.messages.createMessage(
                      MsgKey.ER_WF_INVALID_CHARACTER_IN_NODE_NAME,
                      new Object[] { "Element", node.getNodeName()});
  
              if (fErrorHandler != null) {
                  fErrorHandler.handleError(
                      new DOMErrorImpl(
                          DOMError.SEVERITY_FATAL_ERROR,
                          msg,
                          MsgKey.ER_WF_INVALID_CHARACTER_IN_NODE_NAME,
                          null,
                          null,
                          null));
              }
          }
      }
docs: Checks if an element node is well-formed, by checking its Name for well-formedness.
  
  @param data The contents of the comment node
  @return a boolean indiacating if the comment is well-formed or not.