code: public Observable<ServiceResponse<RouteInner>> createOrUpdateWithServiceResponseAsync(String resourceGroupName, String routeTableName, String routeName, RouteInner routeParameters) {
          if (resourceGroupName == null) {
              throw new IllegalArgumentException("Parameter resourceGroupName is required and cannot be null.");
          }
          if (routeTableName == null) {
              throw new IllegalArgumentException("Parameter routeTableName is required and cannot be null.");
          }
          if (routeName == null) {
              throw new IllegalArgumentException("Parameter routeName is required and cannot be null.");
          }
          if (this.client.subscriptionId() == null) {
              throw new IllegalArgumentException("Parameter this.client.subscriptionId() is required and cannot be null.");
          }
          if (routeParameters == null) {
              throw new IllegalArgumentException("Parameter routeParameters is required and cannot be null.");
          }
          Validator.validate(routeParameters);
          final String apiVersion = "2018-08-01";
          Observable<Response<ResponseBody>> observable = service.createOrUpdate(resourceGroupName, routeTableName, routeName, this.client.subscriptionId(), routeParameters, apiVersion, this.client.acceptLanguage(), this.client.userAgent());
          return client.getAzureClient().getPutOrPatchResultAsync(observable, new TypeToken<RouteInner>() { }.getType());
      }
docs: Creates or updates a route in the specified route table.
  
  @param resourceGroupName The name of the resource group.
  @param routeTableName The name of the route table.
  @param routeName The name of the route.
  @param routeParameters Parameters supplied to the create or update route operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable for the request