/**
   * Sends a signal to the specified resource with a success or failure status. You can use the
   * SignalResource API in conjunction with a creation policy or update policy. AWS CloudFormation
   * doesn't proceed with a stack creation or update until resources receive the required number of
   * signals or the timeout period is exceeded. The SignalResource API is useful in cases where you
   * want to send signals from anywhere other than an Amazon EC2 instance.
   *
   * @param signalResourceRequest The input for the <a>SignalResource</a> action.
   * @sample AmazonCloudFormation.SignalResource
   */
  @Override
  public void signalResource(SignalResourceRequest signalResourceRequest) {
    ExecutionContext executionContext = createExecutionContext(signalResourceRequest);
    AWSRequestMetrics awsRequestMetrics = executionContext.getAwsRequestMetrics();
    awsRequestMetrics.startEvent(Field.ClientExecuteTime);
    Request<SignalResourceRequest> request = null;
    Response<Void> response = null;

    try {
      awsRequestMetrics.startEvent(Field.RequestMarshallTime);
      try {
        request =
            new SignalResourceRequestMarshaller()
                .marshall(super.beforeMarshalling(signalResourceRequest));
        // Binds the request metrics to the current request.
        request.setAWSRequestMetrics(awsRequestMetrics);
      } finally {
        awsRequestMetrics.endEvent(Field.RequestMarshallTime);
      }

      StaxResponseHandler<Void> responseHandler = new StaxResponseHandler<Void>(null);
      invoke(request, responseHandler, executionContext);

    } finally {

      endClientExecution(awsRequestMetrics, request, response);
    }
  }
  /**
   * Validates a specified template.
   *
   * @param validateTemplateRequest The input for <a>ValidateTemplate</a> action.
   * @return Result of the ValidateTemplate operation returned by the service.
   * @sample AmazonCloudFormation.ValidateTemplate
   */
  @Override
  public ValidateTemplateResult validateTemplate(ValidateTemplateRequest validateTemplateRequest) {
    ExecutionContext executionContext = createExecutionContext(validateTemplateRequest);
    AWSRequestMetrics awsRequestMetrics = executionContext.getAwsRequestMetrics();
    awsRequestMetrics.startEvent(Field.ClientExecuteTime);
    Request<ValidateTemplateRequest> request = null;
    Response<ValidateTemplateResult> response = null;

    try {
      awsRequestMetrics.startEvent(Field.RequestMarshallTime);
      try {
        request =
            new ValidateTemplateRequestMarshaller()
                .marshall(super.beforeMarshalling(validateTemplateRequest));
        // Binds the request metrics to the current request.
        request.setAWSRequestMetrics(awsRequestMetrics);
      } finally {
        awsRequestMetrics.endEvent(Field.RequestMarshallTime);
      }

      StaxResponseHandler<ValidateTemplateResult> responseHandler =
          new StaxResponseHandler<ValidateTemplateResult>(
              new ValidateTemplateResultStaxUnmarshaller());
      response = invoke(request, responseHandler, executionContext);

      return response.getAwsResponse();

    } finally {

      endClientExecution(awsRequestMetrics, request, response);
    }
  }
  private <X, Y extends AmazonWebServiceRequest> Response<X> invoke(
      Request<Y> request,
      HttpResponseHandler<AmazonWebServiceResponse<X>> responseHandler,
      ExecutionContext executionContext) {
    request.setEndpoint(endpoint);
    request.setTimeOffset(timeOffset);

    AWSRequestMetrics awsRequestMetrics = executionContext.getAwsRequestMetrics();
    AWSCredentials credentials;
    awsRequestMetrics.startEvent(Field.CredentialsRequestTime);
    try {
      credentials = awsCredentialsProvider.getCredentials();
    } finally {
      awsRequestMetrics.endEvent(Field.CredentialsRequestTime);
    }

    AmazonWebServiceRequest originalRequest = request.getOriginalRequest();
    if (originalRequest != null && originalRequest.getRequestCredentials() != null) {
      credentials = originalRequest.getRequestCredentials();
    }

    executionContext.setCredentials(credentials);

    DefaultErrorResponseHandler errorResponseHandler =
        new DefaultErrorResponseHandler(exceptionUnmarshallers);

    return client.execute(request, responseHandler, errorResponseHandler, executionContext);
  }