How to Make Java MD5 Match PHP and MySQL MD5

Here is Java implementation of MD5 hashing that will produce exactly the same result as
md5()
function in PHP and MySQL:

public static String md5(String input) throws NoSuchAlgorithmException {
    String result = input;
    if(input != null) {
        MessageDigest md = MessageDigest.getInstance("MD5"); //or "SHA-1"
        md.update(input.getBytes());
        BigInteger hash = new BigInteger(1, md.digest());
        result = hash.toString(16);
        if ((result.length() % 2) != 0) {
            result = "0" + result;
        }
    }
    return result;
}