private static final Logger L = LoggerFactory.getLogger(SampleCall.class);

    public static void main(String... args) {

        String key = "API-KEY";
        String secret = "SECRET";
        String hostName = "XXXXXXXX.duosecurity.com";

        DuoGateway gateway = new DuoGateway(newClient(), hostName, key, secret);

        AuthResponse response = gateway.authenticatePasscode("jeff", "647660");
        L.info("Successful?: {}", !response.isError());
        L.info("Allowed?:    {}", response.isAllowed());
        L.info("Message:     {}", response.getMessage().orElse(""));

    }