I can't find anything in the JCo documentation that deals with this. Does this mean that you have to use BAPIs with JCo? Is that bad? How do you map the ifr.sap.com names to BAPI names?
I consider it extremely unlikely that SAP would ever change the name of the function module (RFM) implementing a BAPI. The only case where the argument against hard-coded RFM names would make sense would be that a customer is using the delegation feature of the SAP Business Object Repository (BOR) and has actually overridden a BAPI with his own implementation. I have yet to see a customer who has done that. To be totally on the safe side, you could look up the name of the RFM implementing the BAPI dynamically at runtime. (We sell a metadata server that could be used to do the look-up for you.) In order to use an object-oriented programming approach for the BAPIs in JCo, you could use a proxy generator capable of generating OO proxies (send me an email to get a trial version of our generator).