실행 클래스

import java.util.Scanner;
import java.util.EnumSet;
public class ITAssetManagementSystem {          //main class to execute
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);
        int N = 0;          //The number to control main menu
        while(N != 9){
            System.out.println("IT Asset Management System");                       // Displaying the main menu
            for(MainMenuEnum menu:MainMenuEnum.values()) {                          // and asking the number
                System.out.printf("%d. %s%n", menu.getNum(), menu.getOption());     //
            }                                                                       //
            System.out.print("Enter choice: ");                                     //
            N = sc.nextInt();                      //input the number where user want to go
            System.out.println();
            MainMenuEnum mm;                      // bring the enum of main menu
            if(N==1){                            //the case of "Register Asset"
                mm = MainMenuEnum.RA;        //enter the "Register Asset" menu, so assign the value of Register Asset
                int M = 0;                 //the number to control register menu
                while(M !=3 ) {           //repeat until user choose "Back to main menu"
                    System.out.printf("%s%n",mm.getOption());
                    for (RegisterAssetMenuEnum menu : RegisterAssetMenuEnum.values()) {     //Displaying Register menu
                        System.out.printf("%d. %s%n", menu.getNum(), menu.getOption());     //
                    }
                    System.out.print("Enter choice: ");                                     //and asking the number
                    M = sc.nextInt();                             //input the number where user want to go
                    RegisterAssetMenuEnum RA;                       //bring the enum of register menu
                    if (M == 1) {                          //the case of "Hardware"
                        RA = RegisterAssetMenuEnum.HW;     //enter the "Hardware" menu, so assign the value of Hardware
                        System.out.println("Hardware registration is under development.");
                        System.out.println();
                    } else if (M == 2) {
                        RA = RegisterAssetMenuEnum.SW;
                        System.out.println("Software registration is under development.");
                        System.out.println();
                    } else if (M == 3) {
                        RA = RegisterAssetMenuEnum.BMM;
                        System.out.println();
                    }else{                                      // the case of mistake that user enter other numbers
                        System.out.println("Invalid choice. Please try again.");
                        System.out.println();
                    }                                  //The rest is a repetition of the methods up to this point.
                }
            } else if(N==2){                     //the case of "Search Assets"
                mm = MainMenuEnum.SA;
                int L =0;
                while(L !=4 ) {
                    System.out.printf("%s%n",mm.getOption());
                    for (SearchAssetMenuEnum menu : SearchAssetMenuEnum.values()) {
                        System.out.printf("%d. %s%n", menu.getNum(), menu.getOption());
                    }
                    System.out.print("Enter choice: ");
                    L = sc.nextInt();
                    SearchAssetMenuEnum SA;
                    if (L == 1) {
                        SA = SearchAssetMenuEnum.FS;
                        System.out.println("Full asset search is under development.");
                        System.out.println();
                    } else if (L == 2) {
                        SA = SearchAssetMenuEnum.BH;
                        System.out.println("Hardware asset search is under development.");
                        System.out.println();
                    } else if (L == 3) {
                        SA = SearchAssetMenuEnum.BS;
                        System.out.println("Software asset search is under development.");
                        System.out.println();
                    } else if (L == 4) {
                        SA = SearchAssetMenuEnum.BMM;
                        System.out.println();
                    }else{                                       // the case of mistake that user enter other numbers
                        System.out.println("Invalid choice. Please try again.");
                        System.out.println();
                    }
                }
            } else if(N==9){                      //the case of "Exit"
                mm = MainMenuEnum.ET;
                System.out.println("Exiting...");
            }else{                                         // the case of mistake that user enter other numbers
                System.out.println("Invalid choice. Please try again.");
                System.out.println();
            }
        }

    }
}

메인메뉴 Enum

public enum MainMenuEnum {
    RA(1, "Register Asset"),
    SA(2, "Search Assets"),
    ET(9, "Exit");

    private final int num;
    private final String option;
    MainMenuEnum(int num, String option){
        this.num = num;
        this.option = option;
    }


    public int getNum(){
        return num;
    }

    public String getOption(){
        return option;
    }
}

register asset 메뉴 Enum

public enum RegisterAssetMenuEnum {
    HW(1, "Hardware"),
    SW(2, "Software"),
    BMM(3, "Back to Main Menu");

    private final int num;
    private final String option;
    RegisterAssetMenuEnum(int num, String option){
        this.num = num;
        this.option = option;
    }


    public int getNum(){
        return num;
    }

    public String getOption(){
        return option;
    }
}

search asset 메뉴 Enum

public enum SearchAssetMenuEnum {
    FS(1, "Full Search"),
    BH(2, "By Hardware"),
    BS(3, "By Software"),
    BMM(4,"Back to Main Menu");

    private final int num;
    private final String option;
    SearchAssetMenuEnum(int num, String option){
        this.num = num;
        this.option = option;
    }


    public int getNum(){
        return num;
    }

    public String getOption(){
        return option;
    }
}