code: @Override
      public void throwParseError(String format, Object arg, Object arg2)
          throws XMLStreamException
      {
          String msg = (arg != null || arg2 != null) ?
              MessageFormat.format(format, new Object[] { arg, arg2 }) : format;
          throw constructWfcException(msg);
      }
docs: Throws generic parse error with specified message and current parsing
  location.
  <p>
  Note: public access only because core code in other packages needs
  to access it.