You can use Views feature to limit incoming payload of Refresh and Update messages containing only your preference fids. Using a view, a consumer requests a subset of fields. Then, only the requested fields are sent to EMA application as the diagram shown below:
For more details, please refer to Section 3.2.3 Views in API Concept Guide
Note: ADS supports only field numbers(field names are not supported) and Level 1 data(Market Price) domain for Views feature.
You can find the example of using Views feature in consumer.series300.example360__MarketPrice__View application shipped with Elektron SDK Java package. The example output running the application to request fid no.22(BID) and no.25(ASK):
Hope this help.
One aspect of using views that sometimes surprises: you may see update messages but the fields have not changed value.
This can happen when an update message contains a change to a field value that is not in your view but the message also includes a field that is in your view (but its value has not changed): e.g.:
View : FID 22(BID), FID 25(ASK)
A full update might include: BID= 236.95, BIDSIZE= 11396
Application receives update : BID=236.95
because BID is in the view specification:
Subsequent update includes: BID=236.95, BIDSIZE=9696
Application receives another update : BID=236.95
because BID is in the view specification but the value is the same.