public class UserDao {
    public int save(User user, ServletContext servletContext) {
        int status = 0;
        try{
            Connection con = (Connection) servletContext.getAttribute("databaseCon");
            PreparedStatement ps=con.prepareStatement(
                    "insert into user(name,surname,username,password) values (?,?,?,?)");
            ps.setString(1, user.getName());
            ps.setString(2, user.getSurname());
            ps.setString(3, user.getUsername());
            ps.setString(4, user.getPassword());

            status=ps.executeUpdate();
        }catch(Exception ex){ex.printStackTrace();}

        return status;
    }

    public User validateLogin(String username, String password, Connection connection) {
        User user = new User();

        try {
            PreparedStatement ps = connection.prepareStatement(
                    "select * from user where username = ? and password = ?");
            ps.setString(1, username);
            ps.setString(2, password);

            ResultSet rs = ps.executeQuery();

            if (rs.next()) {
                user.setId(rs.getInt(1));
                user.setName(rs.getString(2));
                user.setSurname(rs.getString(3));
                user.setUsername(rs.getString(4));
                user.setPassword(rs.getString(5));
            }

        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        }

        return user;
    }