For object com.refinitiv.ema.access.Msg how do I make a deep copy of it?

Patrick Sweeney

I want to efficiently take a message from the inbound queue manged by the SDK and add it to a local queue - making this the only function of that thread. A simple assignment is only copying a pointer, not the data itself. Using this pointer later leads to all kinds of data corruption issues as it has been deallocated in the SDK.

Jirapongse

@Patrick Sweeney

The message object passed as a parameter to the callback is owned by SDK. The object and all objects inside that message object must not be used outside the callback.

You can extract the required data, such BID and ASK values from the message and then add it to a local queue, as mentioned by my colleague.

Otherwise, since EMA 3.3.1 (RTSDK C++/C Release 1.3.1.L1), EMA is able to clone and copy messages in order to decode payload outside of message callbacks.

EMA C++ uses a copy constructor.

void AppClient::onRefreshMsg( const RefreshMsg& refreshMsg, const OmmConsumerEvent& ) 
{
    RefreshMsg* msgPtr = new RefreshMsg(refreshMsg);
...
}

EMA Java uses the EMAFactory.

    public void onRefreshMsg(RefreshMsg refreshMsg, OmmConsumerEvent event)
    {        
        RefreshMsg msg = EmaFactory.createRefreshMsg(refreshMsg);
        ...
    }