@SdkInternalApi
    final SendMessageResult executeSendMessage(SendMessageRequest sendMessageRequest) {

        ExecutionContext executionContext = createExecutionContext(sendMessageRequest);
        AWSRequestMetrics awsRequestMetrics = executionContext.getAwsRequestMetrics();
        awsRequestMetrics.startEvent(Field.ClientExecuteTime);
        Request<SendMessageRequest> request = null;
        Response<SendMessageResult> response = null;

        try {
            awsRequestMetrics.startEvent(Field.RequestMarshallTime);
            try {
                request = new SendMessageRequestProtocolMarshaller(protocolFactory).marshall(super.beforeMarshalling(sendMessageRequest));
                // 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, "ConnectParticipant");
                request.addHandlerContext(HandlerContextKey.OPERATION_NAME, "SendMessage");
                request.addHandlerContext(HandlerContextKey.ADVANCED_CONFIG, advancedConfig);

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

            HttpResponseHandler<AmazonWebServiceResponse<SendMessageResult>> responseHandler = protocolFactory.createResponseHandler(
                    new JsonOperationMetadata().withPayloadJson(true).withHasStreamingSuccessResponse(false), new SendMessageResultJsonUnmarshaller());
            response = invoke(request, responseHandler, executionContext);

            return response.getAwsResponse();

        } finally {

            endClientExecution(awsRequestMetrics, request, response);
        }
    }
<p>
Sends a message.
</p>
<note>
<p>
<code>ConnectionToken</code> is used for invoking this API instead of <code>ParticipantToken</code>.
</p>
</note>
<p>
The Amazon Connect Participant Service APIs do not use <a
href="https://docs.aws.amazon.com/general/latest/gr/signature-version-4.html">Signature Version 4
authentication</a>.
</p>

@param sendMessageRequest
@return Result of the SendMessage operation returned by the service.
@throws AccessDeniedException
        You do not have sufficient access to perform this action.
@throws InternalServerException
        This exception occurs when there is an internal failure in the Amazon Connect service.
@throws ThrottlingException
        The request was denied due to request throttling.
@throws ValidationException
        The input fails to satisfy the constraints specified by Amazon Connect.
@sample AmazonConnectParticipant.SendMessage
@see <a href="http://docs.aws.amazon.com/goto/WebAPI/connectparticipant-2018-09-07/SendMessage" target="_top">AWS
     API Documentation</a>
aws-java-sdk-connectparticipant/src/main/java/com/amazonaws/services/connectparticipant/AmazonConnectParticipantClient.java