public Element toElement(Seance seance) {
    Element seanceElement = new Element("seance");
    try {
      seanceElement.setAttribute("startDateTime", new SimpleDateFormat(XML_DATE_FORMAT).format(seance.getStartDateTime().getTime()));
      seanceElement.addContent(new MovieTranslator().toElement(seance.getMovie()));
      seanceElement.addContent(new RoomTranslator().toElement(seance.getRoom()));
    } catch (Exception e) {
      throw new SeanceNotFullException("no room or movie or date", e);
    }
    return seanceElement;
  }