code: public void warning(SAXParseException exception) throws SAXException
    {
      PrintWriter pw = getErrorWriter();
  
      printLocation(pw, exception);
      pw.println("Parser warning: " + exception.getMessage());
    }
docs: Receive notification of a warning.
  
  <p>SAX parsers will use this method to report conditions that
  are not errors or fatal errors as defined by the XML 1.0
  recommendation.  The default behaviour is to take no action.</p>
  
  <p>The SAX parser must continue to provide normal parsing events
  after invoking this method: it should still be possible for the
  application to process the document through to the end.</p>
  
  @param exception The warning information encapsulated in a
  SAX parse exception.
  @throws SAXException Any SAX exception, possibly
  wrapping another exception.