code: public String getMessage ()
      {
      String message = super.getMessage();
  
      if (message == null && exception != null) {
          return exception.getMessage();
      } else {
          return message;
      }
      }
docs: Return a detail message for this exception.
  
  <p>If there is an embedded exception, and if the SAXException
  has no detail message of its own, this method will return
  the detail message from the embedded exception.</p>
  
  @return The error or warning message.