private void doSplitTicket() {
    try {
      Ticket selectedTicket = getFirstSelectedTicket();

      if (selectedTicket == null) {
        return;
      }

      if (!selectedTicket.getTotalAmount().equals(selectedTicket.getDueAmount())) {
        POSMessageDialog.showMessage(POSConstants.PARTIAL_PAID_VOID_ERROR);
        return;
      }

      // initialize the ticket.
      Ticket ticket = TicketDAO.getInstance().loadFullTicket(selectedTicket.getId());

      SplitTicketDialog dialog = new SplitTicketDialog();
      dialog.setTicket(ticket);
      dialog.open();

      updateView();
    } catch (Exception e) {
      POSMessageDialog.showError(POSConstants.ERROR_MESSAGE, e);
    }
  }
  private void doVoidTicket() {
    try {
      Ticket selectedTicket = getFirstSelectedTicket();

      if (selectedTicket == null) {
        return;
      }

      if (!selectedTicket.getTotalAmount().equals(selectedTicket.getDueAmount())) {
        POSMessageDialog.showMessage(POSConstants.PARTIAL_PAID_VOID_ERROR);
        return;
      }

      Ticket ticketToVoid = TicketDAO.getInstance().loadFullTicket(selectedTicket.getId());

      VoidTicketDialog voidTicketDialog = new VoidTicketDialog(Application.getPosWindow(), true);
      voidTicketDialog.setTicket(ticketToVoid);
      voidTicketDialog.open();

      if (!voidTicketDialog.isCanceled()) {
        updateView();
      }
    } catch (Exception e) {
      POSMessageDialog.showError(POSConstants.ERROR_MESSAGE, e);
    }
  }