java 改善案求む。 読みやすいコードについて

Question

テーマ、知りたいこと

java初心者です。
Mapを練習する過程で作ったコードが以下になります。
本職の方から見れば冗長だったり可読性が低いと思うので、改善案があれば教えて下さい。

背景、状況

chatGPTに出された問題の回答として作りました。以下問題文。

問題 4: 学生の年齢と成績を管理
問題: 学生IDをキーとして、名前と複数の成績を管理するプログラムを作成しなさい。

1. 学生IDをキーとし、名前と複数の成績を持つクラス（オブジェクト）を値とする構造にする。
2. 学生情報を追加する。
3. 学生IDを指定してその名前と成績を表示する。
4. すべての学生の情報を表示する。

コード

import java.util.*; 

class Front{
    private StudentsScore studentsScore;
    private Scanner sc;   

    Front(){
        studentsScore = new StudentsScore();
        sc = new Scanner(System.in);
    }

       public void add(){
        System.out.println("Put name : ");
        String name = sc.nextLine();
        int id = makeID();

        while(studentsScore.getStudentsScore().containsKey(id)){
            id = makeID();
        }

        System.out.println("The name is " + name + ". \nYour ID is " + id +". \nHow many subject do you add? ");

        int numOfScore = 0;
        try{
            numOfScore = sc.nextInt();
            String blank = sc.nextLine();
        }catch(Exception e){
            System.out.println("Invalid number");
        }      

        StudentScore studentScore = new StudentScore(name);
        for(int i = 0; i < numOfScore; i++){
            System.out.println("what's subject?");
            String sub = sc.nextLine();
            System.out.println("what's score ?");
            int score = -1;
            try{
               score = sc.nextInt();
            }catch(Exception e){
                System.out.println("Invalid number");
            }

            if(score >= 0) {
                studentScore.setScore(sub,score);
                System.out.println(studentScore.getScore());
                String blank = sc.nextLine();
            }

            else{
                System.out.println("try again? y/n");
                String ans = sc.next();
                String blank = sc.nextLine();

                if(ans.equals("y")) numOfScore++;
                else numOfScore = 0;
            }
        }
        if(!studentScore.getScore().isEmpty()) studentsScore.makeStudent(id,studentScore);
    }

    public void delete(){
        System.out.println("type id: ");
        int id = -1;
        try{
            id = sc.nextInt();
            String blank = sc.nextLine();
        }catch(Exception e){
            System.out.println("Invalid num");
        }
        
        if(id >= 0){
            StudentScore studentScore = studentsScore.getStudentsScore().get(id);
            System.out.println( "id is " + id + ",\nthis student is " + studentScore.getName() + ". \ndo you delete this info? y/n");
            String ans = sc.next();
            if(ans.equals("y")){
                studentsScore.deleteStudent(id);
                System.out.println("Successfully deleted.");
            }else{
                System.out.println("you said no -> back to menu.");
            }
        }
       

    }

    public void find(){
        System.out.println("type id: ");
        int id = -1;
        try{
            id = sc.nextInt();
            String blank = sc.nextLine();
        }catch(Exception e){
            System.out.println("Invalid num");
        }

        if(studentsScore.getStudentsScore().containsKey(id)) {
            StudentScore studentScore = studentsScore.getStudentsScore().get(id);
            System.out.println("you are " + studentScore.getName() + ". \nand your id is " + id + ".\nand your score :");
            for(Map.Entry<String,Integer> score : studentScore.getScore().entrySet()){
                System.out.println("  -" + score.getKey() + " : " + score.getValue());
            }
        }
    }

    public void list(){
        System.out.println("this is the list : ");
        for(Map.Entry<Integer,StudentScore> score : studentsScore.getStudentsScore().entrySet()){
            System.out.println("  - " + score.getValue().getName() + " : " + score.getKey());
        }
    }

    private int makeID(){
        double random = Math.random() * 10000;
        return (int) random;       
    }
}

 
class StudentsScore{
    private Map<Integer,StudentScore> studentsScore;
    StudentsScore(){
        // instance StudentScore?
        studentsScore = new HashMap<>();
    }

    public void makeStudent(Integer iD,StudentScore score){
        studentsScore.put(iD,score);
    }

    public Map<Integer,StudentScore> getStudentsScore(){
        return studentsScore;
    }
    
    public void deleteStudent(int id){
        if(studentsScore.containsKey(id)) studentsScore.remove(id);
    }
}

 class StudentScore{
    private final String name;
    private final Map<String,Integer> score;
    
    StudentScore(String name){
        this.name = name;
        score = new HashMap<>();
    }
    
    public String getName(){
        return this.name;
    }

 public void setScore(String subject,Integer score){
        this.score.put(subject,score);

    }

    public Map<String,Integer> getScore(){
        return score;
    }

}

public class Main{
    public static void main(String[] args) {
        Front front = new Front();
        Scanner sc = new Scanner(System.in);
        boolean notLeave = true;

        while (notLeave){
            System.out.println("---------------------------------\n-MENU \n  -1: add student and their score \n  -2: delete student info \n  -3: find student based on id \n  -4: list all student \n  -any: end");
            String ans = sc.next();

            switch(ans){
                case "1": front.add();break;
                case "2": front.delete();break;
                case "3": front.find();break;
                case "4": front.list();break;
                default: notLeave = false;
            }
        }
    }
}