Converting a file from a directory into an MD5 hash

[tomb1992]

hi, i have some coding that converts a string to an MD5 hash:

import java.math.*;
import java.security.*;

public class MD5 {
public static void main(String args[]) throws Exception{
String s="md5 work";
MessageDigest m=MessageDigest.getInstance("MD5");
m.update(s.getBytes(),0,s.length());
System.out.println("MD5: "+new BigInteger(1,m.digest()).toString(16));
}
}

What i need is for this coding to be able to convert a file from my directory into an MD5 hash, is this possible/easy to do?