code: public static JsonNode from(Controller controller, Router router, Json json) {
          ObjectNode node = json.newObject();
          node.put("classname", controller.getClass().getName())
                  .put("invalid", false)
                  .put("routes", getRoutes(controller, router, json));
          return node;
      }
docs: Creates the Json representation for a valid (exposed) controller.
  
  @param controller the controller
  @param router     the router
  @param json       the json service
  @return the json representation