code: @EventListener
      public void logServiceTicketValidatedEvent(final CasServiceTicketValidatedEvent e) {
          val principal = e.getServiceTicket().getTicketGrantingTicket().getAuthentication().getPrincipal();
          LOGGER.debug(VALIDATED_ST_MSG,
                  e.getServiceTicket().getCreationTime(),
                  e.getServiceTicket().getId(),
                  e.getServiceTicket().getService().getId(),
                  principal.getId(),
                  principal.getAttributes());
      }
docs: Log {@link CasServiceTicketValidatedEvent} at debug level.
  
  @param e the event