public List<Seance> getSeances() {
    List<Seance> seances = new ArrayList<Seance>();
    Seance tempSeance;
    int tempIndex;
    for (Ticket ticket : tickets) {
      tempSeance = ticket.getSeance();
      tempIndex = seances.indexOf(tempSeance);
      if (tempIndex == -1) {
        seances.add(tempSeance);
      } else {
        //        if ( !seances.get(tempIndex).existsTicket(ticket)) {
        //          seances.get(tempIndex).addTicket(ticket);
        //        }
      }
    }
    return seances;
  }