Changing my program to use ArrayList

Question

So I have been given a project in where I must validate ISBN-10 and ISBN-13 numbers. My issue is that I want to use an ArrayList based on what the user inputs(the user adds as many numbers as they want to the ArrayList). Here is my code (without an ArrayList). How can I modify this so that the user can put as many ISBN number as they want?

 public static void main(String args[]) {
        Scanner input = new Scanner(System.in);
        String isbn;
        //Get the ISBN
        System.out.print("Enter an ISBN number ");
        isbn = input.nextLine();
        input.close();

        //Strip out the spaces/System.out.println("Press 1 to enter a list of ISBN numbers to verify. ");System.out.println("Press 1 to enter a list of ISBN numbers to verify. ");dashes by replacing with empty character.
        isbn = isbn.replaceAll("( |-)", "");

        //Check depending on length. 
        boolean isValid = false;
        if(isbn.length()== 10){
            isValid = CheckISBN10(isbn);
        }else if (isbn.length()== 13){
            isValid = CheckISBN13(isbn);

        }else{
            isValid = false;

        }

        //Print check Status
        if(isValid){
            System.out.println(isbn + " IS a valid ISBN");
        }else{
            System.out.println(isbn + " IS NOT a valid ISBN");
        }
    }

    //Checking ISBN-10 numbers are valid
    //
    private static boolean CheckISBN10(String isbn){
        int sum = 0; 
        String dStr;
        for (int d = 0; d < 10; d++){
            dStr = isbn.substring(d, d + 1);
            if (d < 9 || dStr != "X"){
                sum += Integer.parseInt(dStr) * (10-d);
            }else {
                sum += 10;
            }
        }
        return (sum %11 == 10);
    }

    private static boolean CheckISBN13(String isbn){
        int sum = 0; 
        int dVal;
        for (int d = 0; d < 13; d++){
            dVal = Integer.parseInt(isbn.substring(d, d + 1));
            if (d % 2 == 0){
                sum += dVal * 1;
            }else {
                sum += dVal * 3;
            }
        }
        return (sum % 10 == 0);

    }
}

Answer 1

public static List<String> scanNumberToListUntilAppears(String end) {

    if(end == null || end.isEmpty())
        end = "end";

    List<String> numbers = new ArrayList<>();
    String message = "Enter an ISBN number: ";

    try (Scanner input = new Scanner(System.in)) {

        System.out.print(message);
        while(input.hasNext()) {

            String isbn = input.nextLine();
            if(isbn.equalsIgnoreCase(end)) {

                if(!numbers.isEmpty())
                    break;

            } else {

                numbers.add(isbn);
                if(numbers.size() == 1)
                    message = "Enter the next ISBN number or '" + end + "': ";
            } 

            System.out.print(message);
        }
    }

    return numbers;
}

Answer 2

public static void main(String args[]) {
    Scanner input = new Scanner(System.in);
    String isbn;
    String ans;
    ArrayList<String> isbns = new ArrayList<String>();

   // user will enter at least 1 ISBN
    do{
    //Get the ISBN
    System.out.println("Enter an ISBN number ");
    isbns.add(input.nextLine());
    //loops till answer is yes or no
    while(true){
    System.out.println("Would you like to add another ISBN?");
    ans = input.nextLine();
    if(ans.equalsIgnoreCase("no"))
      break;
    else if (!(ans.equalsIgnoreCase("yes"))
      System.out.println("Please say Yes or No");
    }
    }while(!(ans.equalsIgnoreCase("yes"));
    input.close();

    //Strip out the spaces/System.out.println("Press 1 to enter a list of ISBN numbers to verify. ");System.out.println("Press 1 to enter a list of ISBN numbers to verify. ");dashes by replacing with empty character.
    for(int i = 0; i<isbns.size(); i++)
       isbns.set(i, isbns.get(i).replaceAll("( |-)", ""));
    isbn = isbn.replaceAll("( |-)", "");

    //Check depending on length. 
    boolean isValid = false;
   for(String isbn : isbns){
    if(isbn.length()== 10){
        isValid = CheckISBN10(isbn);
        print(isbn, isValid);
    }else if (isbn.length()== 13){
        isValid = CheckISBN13(isbn);
        print(isbn, isValid);
    }else{
        isValid = false;
        print(isbn, isValid);
    }
    }

public static void print(String isbn, boolean isValid){ 
    if(isValid){ 
        System.out.println(isbn + " IS a valid ISBN"); 
    }else{ System.out.println(isbn + " IS NOT a valid ISBN"); 
    }
}

//Checking ISBN-10 numbers are valid
private static boolean CheckISBN10(String isbn){
    int sum = 0; 
    String dStr;
    for (int d = 0; d < 10; d++){
        dStr = isbn.substring(d, d + 1);
        if (d < 9 || dStr != "X"){
            sum += Integer.parseInt(dStr) * (10-d);
        }else {
            sum += 10;
        }
    }
    return (sum %11 == 10);
}

private static boolean CheckISBN13(String isbn){
    int sum = 0; 
    int dVal;
    for (int d = 0; d < 13; d++){
        dVal = Integer.parseInt(isbn.substring(d, d + 1));
        if (d % 2 == 0){
            sum += dVal * 1;
        }else {
            sum += dVal * 3;
        }
    }
    return (sum % 10 == 0);

}