与ArrayList一起循环(Looping with ArrayList)

 我有这个代码，涉及到ArrayList names任务，包括添加ArrayList的元素，显示ArrayList的元素，删除ArrayList的元素，编辑ArrayList的元素等功能。 
 
 我的问题是当我在ArrayList添加一个新名称时，当代码循环回来并且我想查看ArrayList的元素时，结果是空的。 
 
import java.util.ArrayList;
import java.util.Scanner;

public class mainRunner {
    public static void main(String[] args) {
        String con;
        do {
            menuCaller();
            System.out.println("Do you want to continue[Y/N]"); 
            Scanner confirm = new Scanner(System.in);
            con = confirm.nextLine();
        } while (con.equalsIgnoreCase("y"));
    }

    public static void menuCaller() {
        int choice;
        ArrayList names = new ArrayList();
        int firstIndex =0;
        Scanner scan = new Scanner(System.in);
        Scanner scan2 = new Scanner(System.in);
        Scanner scaned = new Scanner(System.in);
        System.out.println("Menu"
                        +"\n[1] Add Name"
                        + "\n[2] Display All Record"
                        + "\n[3] Delete a Record"
                        + "\n[4] Edit a R1ecord "
                        + "\n[5] Exit");

        choice = scaned.nextInt();
        if (choice == 1) {
            System.out.println("***ADDING NAMES***");
            System.out.println("Enter the name of the Student");
            String addName = scan.next();
            names.add(addName);
            System.out.println("Record Added !!!");    
        }
        else if (choice == 2) {
            System.out.println("***Database Content**");
            System.out.println("------------------------");
            System.out.println("Record #   |  Name ");

            for (int index = firstIndex; index < names.size(); ++index) {
                System.out.println("--------------------");
                System.out.println("  " + index + "  |  " +names.get(index));
            }
        }
        else if (choice == 3) {
            System.out.println("***Delete A Record***");
            System.out.print("Enter a number to be deleted: ");
            int numDelete = scan.nextInt();
            names.remove(numDelete);
            System.out.println("Record Deleted");
        }
        else if (choice == 4) {
            System.out.println("***Edit Record***");
            System.out.println("***Database Content**");
            System.out.println("------------------------");
            System.out.println("Record #   |  Name ");

            for (int index = firstIndex; index < names.size(); ++index) {
                System.out.println("--------------------");
                System.out.println("  " + index + "  |  " +names.get(index));
            }

            System.out.println("Enter the Name to be Edited");
            String nameEdited = scan.next();
            if (names.indexOf(nameEdited) >= 0) {
                System.out.print("Change to: ");
                String nameChange = scan2.next();
                names.set(names.indexOf(nameEdited), nameChange);
            }
            else {
                System.out.println("Record Not Existing");
            }
        }
        else if (choice == 5) {
            System.out.println("Thank you for using the Program");
            System.exit(choice);
        }
        else {
            System.out.println("Wrong Choice");
        }
    }
}

I have this code that involves task to do with the ArrayList names that includes functions like adding elements in the ArrayList, displaying the elements of the ArrayList, deleting an element in an ArrayList, editing an element in an ArrayList.
 
My question is when I add a new name in the ArrayList, when the code loops back and I want to view the elements in the ArrayList, it turns out empty.
 
import java.util.ArrayList;
import java.util.Scanner;

public class mainRunner {
    public static void main(String[] args) {
        String con;
        do {
            menuCaller();
            System.out.println("Do you want to continue[Y/N]"); 
            Scanner confirm = new Scanner(System.in);
            con = confirm.nextLine();
        } while (con.equalsIgnoreCase("y"));
    }

    public static void menuCaller() {
        int choice;
        ArrayList names = new ArrayList();
        int firstIndex =0;
        Scanner scan = new Scanner(System.in);
        Scanner scan2 = new Scanner(System.in);
        Scanner scaned = new Scanner(System.in);
        System.out.println("Menu"
                        +"\n[1] Add Name"
                        + "\n[2] Display All Record"
                        + "\n[3] Delete a Record"
                        + "\n[4] Edit a R1ecord "
                        + "\n[5] Exit");

        choice = scaned.nextInt();
        if (choice == 1) {
            System.out.println("***ADDING NAMES***");
            System.out.println("Enter the name of the Student");
            String addName = scan.next();
            names.add(addName);
            System.out.println("Record Added !!!");    
        }
        else if (choice == 2) {
            System.out.println("***Database Content**");
            System.out.println("------------------------");
            System.out.println("Record #   |  Name ");

            for (int index = firstIndex; index < names.size(); ++index) {
                System.out.println("--------------------");
                System.out.println("  " + index + "  |  " +names.get(index));
            }
        }
        else if (choice == 3) {
            System.out.println("***Delete A Record***");
            System.out.print("Enter a number to be deleted: ");
            int numDelete = scan.nextInt();
            names.remove(numDelete);
            System.out.println("Record Deleted");
        }
        else if (choice == 4) {
            System.out.println("***Edit Record***");
            System.out.println("***Database Content**");
            System.out.println("------------------------");
            System.out.println("Record #   |  Name ");

            for (int index = firstIndex; index < names.size(); ++index) {
                System.out.println("--------------------");
                System.out.println("  " + index + "  |  " +names.get(index));
            }

            System.out.println("Enter the Name to be Edited");
            String nameEdited = scan.next();
            if (names.indexOf(nameEdited) >= 0) {
                System.out.print("Change to: ");
                String nameChange = scan2.next();
                names.set(names.indexOf(nameEdited), nameChange);
            }
            else {
                System.out.println("Record Not Existing");
            }
        }
        else if (choice == 5) {
            System.out.println("Thank you for using the Program");
            System.exit(choice);
        }
        else {
            System.out.println("Wrong Choice");
        }
    }
}

原文：