code: public ServiceFuture<ApplicationGatewayInner> createOrUpdateAsync(String resourceGroupName, String applicationGatewayName, ApplicationGatewayInner parameters, final ServiceCallback<ApplicationGatewayInner> serviceCallback) {
          return ServiceFuture.fromResponse(createOrUpdateWithServiceResponseAsync(resourceGroupName, applicationGatewayName, parameters), serviceCallback);
      }
docs: Creates or updates the specified application gateway.
  
  @param resourceGroupName The name of the resource group.
  @param applicationGatewayName The name of the application gateway.
  @param parameters Parameters supplied to the create or update application gateway operation.
  @param serviceCallback the async ServiceCallback to handle successful and failed responses.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceFuture} object