/*******************
     ** DELETE USER **
     ******************/
    /* TA WERSJA MIAŁA DZIAŁAĆ MODYFIKUJAC ID PÓL AUTOINKREMENTOWALNYCH
     * NIESTETY NIE DZIALA PRZEZ TO ZE TE POLA SA UNIKALNE
     * WIEC ZEBY TA WERSJA MIALA SENS, TRZEBA BY WPROWADZIC
     * RECZNE PRZYPISYWANIE ID
    */
    public List<User> deletetUser(String l){

        List<User> users = new LinkedList<User>();

        users = selectUsers();
        boolean isUserFound = false;
        ///getting ID deleted users is required to decrease
        ///id next users, becouse query DELETE
        ///doesnt do that automatically
        int idDeletedUser = 0; //it should be safety becouse
                               // in db fields are incrementing
                               // from 1

        for(User u:users){
            System.out.println(u);
            if ( l.equals(u.getLogin()) ){
                idDeletedUser = u.getId();
                System.out.println("id kasowanego usera: " + idDeletedUser);
                isUserFound = true;
            }
        }

        if(isUserFound){
            ///user will be deleted from db
            try{

                String deleteUser = "DELETE FROM users_table WHERE login='"+l+"'";
                stat.execute(deleteUser);
                System.out.println("DELETE USER command executed!");
            }catch(SQLException e){
                e.printStackTrace();
                return null;
            }
            ///but it still exist at list
            users = selectUsers();

            ///so now users contains list without deleted user
            ///but id variables need to be decreased

            ///when user was last on the list its over..
            System.out.println("users.size()==" + users.size());
            if(idDeletedUser == users.size()){
                 System.out.println("idDeletedUser == users.size()");
                return users;
            }
            //else its time to decrease ids next users
            else{
                System.out.println("! its time to decrease ids next users");
                int i=1; //List is indexed from 1
                for(User u:users){
                    if( (idDeletedUser+1) == u.getId() ){
                        System.out.println("WCHODZE DO IF");
                        //users.get(i).setId(666); //nie mam ustawiac w liscie userowi tylko w bazie
                        try{
                            String updateTable = "UPDATE users_table SET id ="+i;
                            stat.execute(updateTable);
                            System.out.println("updateTable command executed!");
                        }catch(SQLException e){
                            System.out.println("updateTable trhow exception!");
                            e.printStackTrace();
                            return null;
                        }
                        idDeletedUser++;
                    }
                    i++;
                }
            }
            return users;
        }
        else{
            System.out.println("Nie znaleziono takiego usera");
            return users;
        }
    }