public static void login() {

        String user, passwd = "";
        boolean correcto = false;

        System.out.println("Introduce el correo:");
        while (!correcto) {
            user = read.next();
            if (!user.contains("@") || !user.contains(".")) {
                System.err.println("Introduce un formato de email correcto");
            } else {
                correcto = true;
                if (userExists(user)) {
                    //Login
                    System.out.println("Introduce la contraseña:");
                    passwd = read.next();
                    if (checkUserPasswd(user,passwd) != null) {
                        Cliente c = checkUserPasswd(user,passwd);
                        System.out.println("has entrao atontao");
                    }else{
                        System.err.println("Password incorrecta, volviendo al menu...");
                    }

                } else {
                    System.err.println("Este usuario no se encuentra registrado");
                }

            }
        }

    }

    public static boolean userExists(String username) {
        String mailQuery = "SELECT id FROM Cliente WHERE correo = ?";
        ResultSet rs = null;
        Cliente c = null;
        try (
            Connection con = ConnectDB.getInstance();
            PreparedStatement preparedStatement = con.prepareStatement(mailQuery);) {
            preparedStatement.setString(1, username);
            rs = preparedStatement.executeQuery();
            if (rs.next()) {
                return true;
            }
        } catch (SQLException e) {
            System.out.println(e.getErrorCode());
        }finally{
            try {
                ConnectDB.closeConnection();
                rs.close();
            } catch (SQLException ex) {
                Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        return false;
    }

    public static Cliente checkUserPasswd(String username, String passwd){
        String mailQuery = "SELECT * FROM Cliente WHERE correo = ? AND password = ?";
        ResultSet rs = null;
        Cliente c = null;
        try (
            Connection con = ConnectDB.getInstance();
            PreparedStatement preparedStatement = con.prepareStatement(mailQuery);) {
            preparedStatement.setString(1, username);
            preparedStatement.setString(2, passwd);
            rs = preparedStatement.executeQuery();
            if (rs.next()) {
                c = new Cliente();
                c.setId(rs.getInt("id"));
                c.setNombre(rs.getString("nombre"));
                c.setApellido(rs.getString("apellido"));
                c.setDireccion(rs.getString("direccion"));
                c.setCorreo(rs.getString("correo"));
            }
        } catch (SQLException e) {
            System.out.println(e.getErrorCode());
        }finally{
            try {
                ConnectDB.closeConnection();
                rs.close();
            } catch (SQLException ex) {
                Logger.getLogger(Test.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        return c;
    }