Question

Write a Java class which accepts an input argument when the application is executed from the command-line. Add the method reverse(s) which accepts a string as a parameter and returns the string reversed by using the standard charAt() String method.

Answer 1

public class ReverseString {

    public static String reverse(String str) {
        String reverseString = "";
        for(int i = str.length()-1; i >= 0; --i) {
            reverseString += str.charAt(i);
        }
        return reverseString;
    }

    public static void main(String[] args) {
        if (args.length == 0) {
            System.out.println("Please provide a string as command line argument");
        } else {
            System.out.println(args[0] + " in reverse is " + reverse(args[0]));
        }
    }

}