Через интерфейс(JAVA) добавлять информацию В БД

[fallen0002]

У меня есть программа на JAVA школьный журнал. Там есть студенты, их классы, оценки и тд взятые из БД SQL. Теперь же надо через INSERT добавить через интерфейс новый класс (допустим "2Б").
Вот мой интерфейс через него нужно добавить новый класс в БД
Вот интерфейс мое проги
Безымянный.png

Вот классы в моем БД
class.png

а вот код связаны с БД

/*
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package school.database;

import school.database.Grade;
import school.database.SchoolClass;
import school.database.Student;

import java.sql.*;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;


public class DatabaseDAO {

    private static final String URL = "jdbc:mysql://localhost:3306/school_db?useTimezone=true&serverTimezone=GMT";
    private static final String USER = "root";
    private static final String PASSWORD = "123456";

    private static final String GET_ALL_CLASSES_QUERY =
            "SELECT id, name FROM class ORDER BY name";

    private static final String GET_STUDENTS_IN_CLASS_QUERY =
            "SELECT * FROM student WHERE class_id = ?";

    private static final String GET_STUDENT_GRADES_QUERY =
            "SELECT s.name, gv.values, g.grade_date, t.fullname\n" +
                    "FROM grade g JOIN subject s\n" +
                    "ON g.subject_id = s.id\n" +
                    "JOIN student st\n" +
                    "ON g.student_id = st.id\n" +
                    "JOIN grade_value gv\n" +
                    "ON g.grade_id = gv.id\n" +
                    "JOIN teacher t\n" +
                    "ON g.teacher_id = t.id\n" +
                    "WHERE st.id = ?";
    
    private static final String PUT_CLASS_IN_QUERY = "INSERT INTO class (name) VALUES (?)";

    private Connection conn;

    public DatabaseDAO() {
        try {
            conn = DriverManager.getConnection(URL, USER, PASSWORD);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }

    public ArrayList<SchoolClass> readAllClassesFromDB() {
        ArrayList<SchoolClass> result = new ArrayList<>();

        try (PreparedStatement stmt = conn.prepareStatement(GET_ALL_CLASSES_QUERY)) {
            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                int id = rs.getInt("id");
                String name = rs.getString("name");
                SchoolClass schoolClass = new SchoolClass(id, name);
                result.add(schoolClass);
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

        return result;
    }

    public ArrayList<Student> readStudentsInClassFromDB(int classID) {
        ArrayList<Student> result = new ArrayList<>();

        try (PreparedStatement stmt = conn.prepareStatement(GET_STUDENTS_IN_CLASS_QUERY)) {
            stmt.setInt(1, classID);
            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                int studentID = rs.getInt("id");
                String firstName = rs.getString("name");
                String lastName = rs.getString("surname");
                Date birthday = rs.getDate("birthday");
                Student student = new Student(studentID, firstName, lastName, "PATRON", birthday);
                result.add(student);
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

        return result;
    }

    public ArrayList<Grade> readGradesFromDB(int studentID) {
        ArrayList<Grade> result = new ArrayList<>();

        try (PreparedStatement stmt = conn.prepareStatement(GET_STUDENT_GRADES_QUERY)) {
            stmt.setInt(1, studentID);
            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                String subject = rs.getString("name");
                int value = rs.getInt("values");
                java.util.Date date = rs.getDate("grade_date");
                String teacher = rs.getString("fullname");
                Grade grade = new Grade(subject, value, date);
                grade.setTeacher(teacher);
                result.add(grade);
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

        return result;
    }
    
    

    public boolean writeClassinDB(Class class) {
	boolean result = false;
	PreparedStatement stmt;
        try {
            stmt = conn.prepareStatement(PUT_CLASS_IN_QUERY);
        } catch (SQLException ex) {
            Logger.getLogger(DatabaseDAO.class.getName()).log(Level.SEVERE, null, ex);
        }
        try {
            stmt.setString(1, class.getName());
            
            if(stmt.executeUpdate() == 1){
		
		result = true;
            } 

        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

        return result;
    }
}

Код интерфейса можете помочь написать чтобы через него добавлялась информация в бд

package school.frames;

import school.Main;
import school.database.SchoolClass;

import javax.management.openmbean.KeyAlreadyExistsException;
import javax.swing.*;

public class CreateClassFrame extends MyFrame {

    private static Integer[] nums = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};
    private static Character[] letters = {'А', 'Б', 'В', 'Г'};

    public CreateClassFrame(JFrame parent) {
        super("Создать класс", parent, 250, 150);
    }

    public void showFrame() {
        JLabel numLabel = new JLabel("Номер класса: ");
        numLabel.setBounds(10, 10, 150, 25);
        JComboBox<Integer> numsBox = new JComboBox<>(nums);
        numsBox.setBounds(150, 10, 90, 25);

        JLabel letterLabel = new JLabel("Буква класса: ");
        letterLabel.setBounds(10, 45, 150, 25);
        JComboBox<Character> lettersBox = new JComboBox<>(letters);
        lettersBox.setBounds(150, 45, 90, 25);

        JButton cancel = new JButton("Отмена");
        cancel.setBounds(10, 90, 110, 25);
        cancel.addActionListener(actionEvent -> dispose());

        JButton done = new JButton("Готово");
        done.setBounds(130, 90, 110, 25);
        done.addActionListener(actionEvent -> {
            try {
                if (numsBox.getSelectedItem() != null && lettersBox.getSelectedItem() != null) {
                    Main.addClass(new SchoolClass(0, "" + (Integer) numsBox.getSelectedItem() + (Character) lettersBox.getSelectedItem()));
                    dispose();
                }
            } catch (KeyAlreadyExistsException e) {
                JOptionPane.showMessageDialog(this, "Класс " + e.getMessage() + " уже существует");
            }
        });

        add(numLabel);
        add(numsBox);
        add(letterLabel);
        add(lettersBox);
        add(cancel);
        add(done);

        setVisible(true);
    }

}