@Override
    public Object getValueAt(int rowIndex, int columnIndex) {
        Room room = rooms.get(rowIndex);

        switch (columnIndex) {
            case -1:
                return room;
            case 0:
                return room.getNumber();
            case 1:
                return room.getCapacity();
            case 2:
                return room.getPricePerDay();
            case 3:
                return checked[rowIndex];
            default:
                throw new IndexOutOfBoundsException("No data for column index " + columnIndex);
        }
    }