Inserting Zeros at Starting Left of the Number and String using Java

import java.io.BufferedReader;
import java.io.InputStreamReader;
class DemoLeft
{
    public static void main(String[] arg) throws Exception
    {
        BufferedReader in = new BufferedReader(new InputStreamReader(System. in ));
        System.out.println("1-Left insertion with zeros at the start of ''Number''");
        System.out.println("2-Left insertion with zeros at the start of ''String''");
        System.out.println();
        System.out.print("Select any option: ");
        int select = Integer.parseInt( in .readLine());
        switch (select)
        {
            case 1:
                System.out.println("After insertion: " + ">" + padLeft(143, 14) + "<");
                break;
            case 2:
                String s = padLeft("Excellent", 14);
                System.out.println("After insertion: " + ">" + s.replace(" ", "0") + "<");
                break;
            default:
                System.out.println("Wrong choice");
        }
    }
    public static String padLeft(int s, int n)
    {
        return String.format("%0" + n + "d", s);
    }
    public static String padLeft(String s, int n)
    {
        return String.format("%0$" + n + "s", s);
    }
}