I found the problem: PlusAnon.... always includes the anonymous user
when you ask it for the User iterator: getUserIDs();
However, if you don't have your pref array poked into it,
getPreferencesFromUser() for the anonymous user returns null instead of
an empty preference list.
MemoryDiffStorage walks the preferences at startup. This includes the
anonymous user, it gets a null, and throws a NullPointerException. If
PlusAnon... must always include the anonymous user (and I think it
should), it should return a zero-length PreferenceArray rather than a
null pointer. That is, the anonymous user has no opinions.
Would this screw up various recommender algorithms?
Lance Norskog wrote:
Does anyone have an example of successfully using
PlusAnonymousUserDataModel? There are no unit tests for it. I'm
playing around and finding one problem after another in various
classes; they do things that don't fit with how PAUDM works.
Lance
