StringCounter

public class StringCounter {

    public static void main(String[] args) {
        String input = args[0];
        String target = args[1];

        System.out.println("Count: " + StringCount(input, target));
    }

    public static int StringCount(String input, String target) {

        if (input == null || input.isEmpty()) // Null/Empty check prevents infinite loop.
            return 0;
        else if (input.length() == 1) { // Last character in the input string
            if (input.equals(target))
                return 1;
            else
                return 0;
        } else { // Recursive calls checking the first character of the intput string
            if (input.substring(0, 1).equals(target))
                return 1 + StringCount(input.substring(1), target);
            else
                return StringCount(input.substring(1), target);
        }
    }
}