@Override
    public Object getValueAt(int rowIndex, int columnIndex) {
        Artist artist = artists.get(rowIndex);
        switch(columnIndex){
            case -1 : return artist.getId();     // imam id iz baze, ali ga ne prikazujem
            case 0 : return artist.getFirstName();
            case 1 : return artist.getLastName();
            case 2 : return artist.getBody();
            case 3 : return artist.getKind();
            case 4 : return "izmeni";
            case 5 : return "obrisi";
            default : return "GRESKA!";
        }
    }