@SdkInternalApi
    final EventSubscription executeModifyEventSubscription(ModifyEventSubscriptionRequest modifyEventSubscriptionRequest) {

        ExecutionContext executionContext = createExecutionContext(modifyEventSubscriptionRequest);
        AWSRequestMetrics awsRequestMetrics = executionContext.getAwsRequestMetrics();
        awsRequestMetrics.startEvent(Field.ClientExecuteTime);
        Request<ModifyEventSubscriptionRequest> request = null;
        Response<EventSubscription> response = null;

        try {
            awsRequestMetrics.startEvent(Field.RequestMarshallTime);
            try {
                request = new ModifyEventSubscriptionRequestMarshaller().marshall(super.beforeMarshalling(modifyEventSubscriptionRequest));
                // Binds the request metrics to the current request.
                request.setAWSRequestMetrics(awsRequestMetrics);
                request.addHandlerContext(HandlerContextKey.CLIENT_ENDPOINT, endpoint);
                request.addHandlerContext(HandlerContextKey.ENDPOINT_OVERRIDDEN, isEndpointOverridden());
                request.addHandlerContext(HandlerContextKey.SIGNING_REGION, getSigningRegion());
                request.addHandlerContext(HandlerContextKey.SERVICE_ID, "RDS");
                request.addHandlerContext(HandlerContextKey.OPERATION_NAME, "ModifyEventSubscription");
                request.addHandlerContext(HandlerContextKey.ADVANCED_CONFIG, advancedConfig);

            } finally {
                awsRequestMetrics.endEvent(Field.RequestMarshallTime);
            }

            StaxResponseHandler<EventSubscription> responseHandler = new StaxResponseHandler<EventSubscription>(new EventSubscriptionStaxUnmarshaller());

            response = invoke(request, responseHandler, executionContext);

            return response.getAwsResponse();

        } finally {

            endClientExecution(awsRequestMetrics, request, response);
        }
    }
<p>
Modifies an existing RDS event notification subscription. You can't modify the source identifiers using this
call. To change source identifiers for a subscription, use the <code>AddSourceIdentifierToSubscription</code> and
<code>RemoveSourceIdentifierFromSubscription</code> calls.
</p>
<p>
You can see a list of the event categories for a given source type (<code>SourceType</code>) in <a
href="https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_Events.html">Events</a> in the <i>Amazon RDS
User Guide</i> or by using the <code>DescribeEventCategories</code> operation.
</p>

@param modifyEventSubscriptionRequest
@return Result of the ModifyEventSubscription operation returned by the service.
@throws EventSubscriptionQuotaExceededException
        You have reached the maximum number of event subscriptions.
@throws SubscriptionNotFoundException
        The subscription name does not exist.
@throws SNSInvalidTopicException
        SNS has responded that there is a problem with the SNS topic specified.
@throws SNSNoAuthorizationException
        You do not have permission to publish to the SNS topic ARN.
@throws SNSTopicArnNotFoundException
        The SNS topic ARN does not exist.
@throws SubscriptionCategoryNotFoundException
        The supplied category does not exist.
@sample AmazonRDS.ModifyEventSubscription
@see <a href="http://docs.aws.amazon.com/goto/WebAPI/rds-2014-10-31/ModifyEventSubscription" target="_top">AWS
     API Documentation</a>
aws-java-sdk-rds/src/main/java/com/amazonaws/services/rds/AmazonRDSClient.java