public static String hashToString(byte[] hash) {
        StringBuffer hexString = new StringBuffer();
        for (int i = 0; i < hash.length; i++)
        {
            String hex = Integer.toHexString(0xFF & hash[i]);
            if (hex.length() == 1)
            {
                hexString.append('0');
            }
            hexString.append(hex);
        }
        return hexString.toString();
    }