Knuth moris pratt in java

package kws.algo.string;

import java.util.Arrays;

/**
 * Created by IntelliJ IDEA.
 * User: uchan
 * Date: 3/27/12
 * Time: 9:10 AM
 * To change this template use File | Settings | File Templates.
 */
public class KnuthMorrisPratt {

    public void match(char[] t, char[] p) {
        short [] pi = calculatePi(p);
        int q = 0; //number of character matched
        for(int i = 0; i < t.length; i++) {
            while(q > 0 && p[q] != t[i]){
               q = pi[q-1];
            }
            if(p[q] == t[i]) {
                q = q + 1;
            }
            if(q == p.length) {
                System.out.println("Pattern found ");
                q = pi[q-1];
            }
        }
    }

    private short[] calculatePi(char[] p) {
        short [] pi = new short[p.length];
        pi[0] = 0;
        int k = 0;
        for (int i = 1; i < p.length; i++) {
            while(k > 0 && p[k] != p[i]) {
               k = pi[k-1];
           }
           if(p[k] == p[i]) {
                k = k + 1;
           }
            pi[i] = (short) k;
        }
        return pi;
    }
    
    public static void main(String ... arg) {
        KnuthMorrisPratt knuthMorrisPratt = new KnuthMorrisPratt();
        knuthMorrisPratt.match("xaababacahsababacagadfasd".toCharArray(), "ababaca".toCharArray());
    }
}