private String buildTopic()

in iothub/device/iot-device-client/src/main/java/com/microsoft/azure/sdk/iot/device/transport/mqtt/MqttTwin.java [81:140]
54 lines of code
8 McCabe index (conditional complexity)

    private String buildTopic(final IotHubTransportMessage message)
    {
        StringBuilder topic = new StringBuilder();
        switch (message.getDeviceOperationType())
        {
            case DEVICE_OPERATION_TWIN_GET_REQUEST:
            {
                //Building $iothub/twin/GET/?$rid={request id}
                topic.append(GET);

                String reqid = message.getRequestId();
                if (reqid != null && reqid.length() > 0)
                {
                    topic.append(BACKSLASH);
                    topic.append(REQ_ID);
                    topic.append(reqid);
                }
                else
                {
                    throw new IllegalArgumentException("Request Id is Mandatory");
                }
                break;
            }
            case DEVICE_OPERATION_TWIN_UPDATE_REPORTED_PROPERTIES_REQUEST:
            {
                // Building $iothub/twin/PATCH/properties/reported/?$rid={request id}&$version={base version}
                topic.append(PATCH);
                topic.append(BACKSLASH);
                topic.append(PROPERTIES);
                topic.append(BACKSLASH);
                topic.append(REPORTED);

                String reqid = message.getRequestId();
                if (reqid != null && reqid.length() > 0)
                {
                    topic.append(BACKSLASH);
                    topic.append(REQ_ID);
                    topic.append(message.getRequestId());
                }
                else
                {
                    throw new IllegalArgumentException("Request Id is Mandatory");
                }

                Integer version = message.getVersion();
                if (version != null) {
                    topic.append(AND);
                    topic.append(VERSION);
                    topic.append(version);
                }
                break;
            }
            default:
            {
                throw new UnsupportedOperationException("Device Twin Operation is not supported - " + message.getDeviceOperationType());
            }
        }

        return topic.toString();
    }