java and reading from .txt files

Question

public class CreditCardHolder
{
/**
 * This method is used to hold credit card numbers
 */
    public static void main(String[] args) throws Exception
    {
        File cardNumbers = new File("creditcardnumbers.txt");
        Scanner cardNumbersInput = new Scanner(cardNumbers);

        cardNumbersInput.useDelimiter("|" + System.getProperty("line.separator"));

        while(cardNumbersInput.hasNextInt())
        {
            int cardNumber = Integer.parseInt(cardNumbersInput.next());
            System.out.printf("%d", cardNumber);
        }

        cardNumbersInput.close();
    }

WHy is this only printing the first line in my .txt file i need it to print whatever is in the file i currently have four numbers like so
4929253776358751
4716026803447186
4539032933695186
5473350227612088

Answer 1

Change to:

public static void main(String[] args) throws FileNotFoundException{
    File cardNumbers = new File("creditcardnumbers.txt");
    Scanner cardNumbersInput = new Scanner(cardNumbers);

    while(cardNumbersInput.hasNextLine()) {
        String cardNumber = cardNumbersInput.nextLine();
        System.out.println(cardNumber);
    }

    cardNumbersInput.close();
}

test hasNextLine() instead hasNextInt() and use nextLine() instead nextInt() as well since you needn't to parse/format anything. For simplicity you should use println instead printf since you have no formatting or so one. And of course avoid use custom delimitter assuming the default one.