Passing TransferFile into custom ServiceHandler

While working with WebContent server 12.2.1.2, on the client side we are creating DataBinder from namespace 

oracle.stellent.ridc.model.DataBinder with help of method

idcClient.createBinder();

This binder has a method addFile with parameter TransferFile. We are using this in following way.

binder.addFile("convertedFile", transferFile);

So far, so good. But how can we obtain this parameter in custom ServiceHandler?

There we are using DataBinder from namespace intradoc.data.DataBinder which 

does not have this method.

Can you please explain us how to proceed here?

Thank you