Java - Write code to Place a post fix on a filename just before the extension dot.

Requirements

Write code to Place a post fix on a filename just before the extension dot.

Demo

//package com.book2s;

public class Main {
    public static void main(String[] argv) {
        String filename = "book2s.com";
        String postfix = "book2s.com";
        System.out.println(postfixFilename(filename, postfix));
    }/*from   w ww . j  a  v  a  2 s.co  m*/

    /**
     * Places a post fix on a filename just before the extension dot.
     */
    public static String postfixFilename(String filename, String postfix) {
        int index = filename.lastIndexOf(".");
        return (filename.substring(0, index) + postfix + filename
                .substring(index));
    }
}

Related Exercise