code: @Override
      public StartGatewayResult startGateway(StartGatewayRequest request) {
          request = beforeClientExecution(request);
          return executeStartGateway(request);
      }
docs: <p>
  Starts a gateway that you previously shut down (see <a>ShutdownGateway</a>). After the gateway starts, you can
  then make other API calls, your applications can read from or write to the gateway's storage volumes and you will
  be able to take snapshot backups.
  </p>
  <note>
  <p>
  When you make a request, you will get a 200 OK success response immediately. However, it might take some time for
  the gateway to be ready. You should call <a>DescribeGatewayInformation</a> and check the status before making any
  additional API calls. For more information, see <a>ActivateGateway</a>.
  </p>
  </note>
  <p>
  To specify which gateway to start, use the Amazon Resource Name (ARN) of the gateway in your request.
  </p>
  
  @param startGatewayRequest
  A JSON object containing the of the gateway to start.
  @return Result of the StartGateway operation returned by the service.
  @throws InvalidGatewayRequestException
  An exception occurred because an invalid gateway request was issued to the service. For more information,
  see the error and message fields.
  @throws InternalServerErrorException
  An internal server error has occurred during the request. For more information, see the error and message
  fields.
  @sample AWSStorageGateway.StartGateway
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/storagegateway-2013-06-30/StartGateway" target="_top">AWS
  API Documentation</a>