code: private void validateMessageForNull(Message msg) throws MessageFormatException {
  
          // if the supplied message is null, throw a jms MessageFormatException.
          if (msg == null) {
              throw (MessageFormatException) JmsErrorUtils.newThrowable(
                                                                        MessageFormatException.class,
                                                                        "INVALID_VALUE_CWSIA0068",
                                                                        new Object[] { "message", null },
                                                                        tc);
          }
      }
docs: Validates if Message is NULL. If it is null throws MessageFormatException
  
  @param cListener
  
  @throws IllegalArgumentException