@Override
    public boolean isCellEditable(int rowIndex, int columnIndex) {
	switch (COLUMNS.values()[columnIndex]) {
	    case ID:
	    case CUSTOMER:
	    case CAR:
		return false;
	    case FROM:
	    case TO:
	    case COST:
		return true;
	    default:
		throw new IllegalArgumentException("columnIndex");
	}
    }