code: @Override
      public GetServiceGraphResult getServiceGraph(GetServiceGraphRequest request) {
          request = beforeClientExecution(request);
          return executeGetServiceGraph(request);
      }
docs: <p>
  Retrieves a document that describes services that process incoming requests, and downstream services that they
  call as a result. Root services process incoming requests and make calls to downstream services. Root services
  are applications that use the AWS X-Ray SDK. Downstream services can be other applications, AWS resources, HTTP
  web APIs, or SQL databases.
  </p>
  
  @param getServiceGraphRequest
  @return Result of the GetServiceGraph operation returned by the service.
  @throws InvalidRequestException
  The request is missing required parameters or has invalid parameters.
  @throws ThrottledException
  The request exceeds the maximum number of requests per second.
  @sample AWSXRay.GetServiceGraph
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/xray-2016-04-12/GetServiceGraph" target="_top">AWS API
  Documentation</a>