@Override
    public Class<?> getColumnClass(int columnIndex) {
	switch (COLUMNS.values()[columnIndex]) {
	    case ID:
		return Integer.class;
	    case FIRSTNAME:
	    case LASTNAME:
	    case EMAIL:
		return String.class;
	    case BIRTH:
		return Date.class;
	    default:
		throw new IllegalArgumentException("columnIndex");
	}
    }