public static void main(String[] args) throws UnknownHostException { MongoClient client = new MongoClient(new ServerAddress("localhost", 27017)); final DB db = client.getDB("course"); Spark.get( new Route("/") { @Override public Object handle(Request request, Response response) { DBCollection users = db.getCollection("user"); DBObject user = users.findOne(); StringWriter writer = new StringWriter(); Configuration configuration = new Configuration(); configuration.setClassForTemplateLoading( HelloWorldMongoDBSparkFreemarkerStyle.class, "/"); try { Template template = configuration.getTemplate("hello.ftl"); template.process(user, writer); } catch (Exception e) { halt(100); e.printStackTrace(); } return writer; } }); }