code: @Override
      public UpdateNumberOfDomainControllersResult updateNumberOfDomainControllers(UpdateNumberOfDomainControllersRequest request) {
          request = beforeClientExecution(request);
          return executeUpdateNumberOfDomainControllers(request);
      }
docs: <p>
  Adds or removes domain controllers to or from the directory. Based on the difference between current value and
  new value (provided through this API call), domain controllers will be added or removed. It may take up to 45
  minutes for any new domain controllers to become fully active once the requested number of domain controllers is
  updated. During this time, you cannot make another update request.
  </p>
  
  @param updateNumberOfDomainControllersRequest
  @return Result of the UpdateNumberOfDomainControllers operation returned by the service.
  @throws EntityDoesNotExistException
  The specified entity could not be found.
  @throws DirectoryUnavailableException
  The specified directory is unavailable or could not be found.
  @throws DomainControllerLimitExceededException
  The maximum allowed number of domain controllers per directory was exceeded. The default limit per
  directory is 20 domain controllers.
  @throws InvalidParameterException
  One or more parameters are not valid.
  @throws UnsupportedOperationException
  The operation is not supported.
  @throws ClientException
  A client exception has occurred.
  @throws ServiceException
  An exception has occurred in AWS Directory Service.
  @sample AWSDirectoryService.UpdateNumberOfDomainControllers
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/ds-2015-04-16/UpdateNumberOfDomainControllers"
  target="_top">AWS API Documentation</a>