Greatest product of five consecutive digits in a 1000-digit number

Question

I am working through the problems on project Euler and am not too certain if my understanding of the question is correct.

Problem 8 is as follows:

Answer 1

Only improvisation in my solution is, avoiding unnecessary computations by looking ahead.

package com.euler;

public class Euler8 {
    public static void main(String[] ar) throws Exception {
        String s = 
                "73167176531330624919225119674426574742355349194934" + 
                "96983520312774506326239578318016984801869478851843" + 
                "85861560789112949495459501737958331952853208805511" + 
                "12540698747158523863050715693290963295227443043557" + 
                "66896648950445244523161731856403098711121722383113" + 
                "62229893423380308135336276614282806444486645238749" + 
                "30358907296290491560440772390713810515859307960866" + 
                "70172427121883998797908792274921901699720888093776" + 
                "65727333001053367881220235421809751254540594752243" + 
                "52584907711670556013604839586446706324415722155397" + 
                "53697817977846174064955149290862569321978468622482" + 
                "83972241375657056057490261407972968652414535100474" + 
                "82166370484403199890008895243450658541227588666881" + 
                "16427171479924442928230863465674813919123162824586" + 
                "17866458359124566529476545682848912883142607690042" + 
                "24219022671055626321111109370544217506941658960408" + 
                "07198403850962455444362981230987879927244284909188" + 
                "84580156166097919133875499200524063689912560717606" + 
                "05886116467109405077541002256983155200055935729725" + 
                "71636269561882670428252483600823257530420752963450" ;
        Integer[] tokens = new Integer[s.length()];
        for (int i = 0; i < s.length(); i++) {
            tokens[i] = (int) s.charAt(i)-48;
        }

        int prod = 1;
        int[] numberSet = new int[5];
        int prodCounter = 1;
        for (int i=0; i