code: public Observable<ConfigurationInner> beginCreateOrUpdateAsync(String resourceGroupName, String serverName, String configurationName, ConfigurationInner parameters) {
          return beginCreateOrUpdateWithServiceResponseAsync(resourceGroupName, serverName, configurationName, parameters).map(new Func1<ServiceResponse<ConfigurationInner>, ConfigurationInner>() {
              @Override
              public ConfigurationInner call(ServiceResponse<ConfigurationInner> response) {
                  return response.body();
              }
          });
      }
docs: Updates a configuration of a server.
  
  @param resourceGroupName The name of the resource group that contains the resource. You can obtain this value from the Azure Resource Manager API or the portal.
  @param serverName The name of the server.
  @param configurationName The name of the server configuration.
  @param parameters The required parameters for updating a server configuration.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the ConfigurationInner object