NSDocument has a whole huge hierarchy of methods involved in reading and writing data. Which one you should override depends a lot on the specifics of your particular situation and how they relate to the default read/write machinery. My gut reaction when I saw this question was that you don't want to be overriding the -save*
methods, you want to be overriding a -write*
method (probably -writeToURL:ofType:forSaveOperation:originalContentsURL:error:
), but it's really hard to say without knowing more about the specifics of your app (and this third party library you're using.)
The definitive discussion of the various override points and situations where they're suitable is here.