User.java

import java.util.*;

public class User {
    private int userId;
    private String username;
    private String password;
    private String email;
    private List<Notebook> notebooks;

    public User(int userId, String username, String password, String email) {
        this.userId = userId;
        this.username = username;
        this.password = password;
        this.email = email;
        this.notebooks = new ArrayList<>();
    }

    public void createNotebook(String name) {
        notebooks.add(new Notebook(name));
    }

    public void deleteNotebook(String name) {
        notebooks.removeIf(nb -> nb.getName().equalsIgnoreCase(name));
    }

    public List<Notebook> getNotebooks() {
        return notebooks;
    }

    public String getUsername() { return username; }
    public int getUserId() {
    return userId;
}
    public String getPassword() { return password; }
    public String getEmail() {
    return email;
}
}