Hello @bhavya.dudhia

If you are migrating from the legacy RFA version 5, I strongly suggest you migrate to the strategic Enterprise Message API (EMA API) of the Real-Time SDK Java edition. The EMA is the open-source Message level API that can connect and consume data from the LSEG Real-Time Platform via the RSSL connection (the same as RFA 8). The EMA API let you interact with the connection and OMM data via easier to use API interfaces than the RFA API.

• Choosing a Real-time Streaming API
• Migrating from the Legacy Robust Foundation API (RFA) to the Enterprise Message API (EMA)<-- Recommend reading.
• RTSDK Java - GitHub
• EMA Consumer Tutorials
• Developer Webinar: Introduction to Enterprise App Creation With Open-Source Enterprise Message API<-- Recommend checking

The example code of the EMA Consumer API is as follows:

// Process Incoming Data
class AppClient implements OmmConsumerClient{
    public void onRefreshMsg(RefreshMsg refreshMsg, OmmConsumerEvent event){
        //Process Refresh Msg
    }
    
    public void onUpdateMsg(UpdateMsg updateMsg, OmmConsumerEvent event) {
        //Process Update Msg
    }


    public void onStatusMsg(StatusMsg statusMsg, OmmConsumerEvent event) {
        //Process Status Msg
    }
    
    public void onGenericMsg(GenericMsg genericMsg, OmmConsumerEvent consumerEvent){}
    public void onAckMsg(AckMsg ackMsg, OmmConsumerEvent consumerEvent){}
    public void onAllMsg(Msg msg, OmmConsumerEvent consumerEvent){}
    
}


public class Consumer {
    public static void main(String[] args){
        OmmConsumer consumer = null;
        try
        {
            AppClient appClient = new AppClient();
            
            //Establish a connection and send OMM Login Request to the Real-Time Platform
            consumer  = EmaFactory.createOmmConsumer(EmaFactory.createOmmConsumerConfig().host("localhost:14002").username("user"));
            
            //Send Item Request to to the Real-Time Platform
            consumer.registerClient(EmaFactory.createReqMsg().serviceName("IDN_RDF").name("IBM.N"), appClient);
            
            Thread.sleep(60000);            // API calls onRefreshMsg(), onUpdateMsg() and onStatusMsg()
        }
        catch (InterruptedException | OmmException excp)
        {
            System.out.println(excp.getMessage());
        }
        finally 
        {
            if (consumer != null) consumer.uninitialize();
        }
    }
}

You may notice that the EMA API uses the callback methods to process each message type as follows:

• Refresh/Image message: onRefreshMsg()
• Update messages: onUpdateMsg()
• Status messages: onStatusMsg()

An application can choose to let the API automatic dispatches incoming messages to those callback methods, or an application can dispatch them manually. The suggested examples to check ares:

• Cons100 example, the easiest one
• Cons200 example

Hello @bhavya.dudhia

Please note that the RFA MarketFeed class cannot be compared to the EMA (and RFA) OMM class one-by-one. However, some comparisons are as follows:

### Event.MARKET_DATA_SVC_EVENT ###

Like I said above, the EMA API automatic dispatches messages to a valid callback methods.

• Refresh/Image message: onRefreshMsg()
• Update messages: onUpdateMsg()
• Status messages: onStatusMsg()
• Ack messages: onAckMsg()
• Generic Messages: onGenericMsg

However, there is the com.refinitiv.ema.access.Msg class that represents all message types. It has the domainType() method that returns the message's domain type information.

### MarketDataItemEvent.IMAGE ###

In the EMA, the Refresh message class is com.refinitiv.ema.access.RefreshMsg.

### Market DataItemEvent.UPDATE ###

In the EMA, the Refresh message class is com.refinitiv.ema.access.UpdateMsg.

### MarketDataItemEvent.UNSOLICITED_IMAGE ###

The Unsolicited or Solicited information is now part of the Refresh Message attributes:

Please see EMA J RDM Usage Guide for more detail

### CORRECTION, CLOSING_RUN, etc. ###

This information as now part of the Update Message UpdateTypeNum component. Please see my colleague answer on this How to detect closing run events? old post for more detail.