Parsing Strings into Fixed Length Tokens

import java.util.Scanner;

public class Delim {
    static int i = 0;

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String str = sc.next();
        String token;
        while(true) {
            token = splitter(str, 3);
            if (token == null) {
                return;
            }
            System.out.println(token);
        }
    }
 
    public static String splitter(String str, int numChars) {
        int j = numChars + i;
        if (j > str.length()) {
            i = 0;
            return null;
        }
        String token = str.substring(i, j);
        i += numChars;
        return token;
    }
}