> It doesn't seem like the members of an EnumSet would be iterated frequently...
We use EnumSet and EnumMap extensively, frequently iterating over them (the enum's natural order being critical). > ...usually treated as a bag of named booleans used as a set of boolean options. So for us it's... "ordered bag of named booleans with cheap lookup". But I agree our usage probably wouldn't benefit from sequenced/navigable functionality much (if at all). -- Aaron Scott-Boddendijk On Wed, May 24, 2023 at 5:51 AM Stuart Marks <stuart.ma...@oracle.com> wrote: > The idea of EnumSet implementing SortedSet or NavigableSet has been around > for a long time; see > > https://bugs.openjdk.org/browse/JDK-6278287 > > But yes, EnumSet could also implement SequencedSet. Similarly, EnumMap > could implement SequencedMap, SortedMap, or NavigableMap. > > Implementing NavigableSet/Map is somewhat onerous, given that there's no > AbstractNavigableSet/Map, and there are a lot of methods and variations of > views to be implemented. > > I'm a bit skeptical about the usefulness of retrofitting EnumSet/Map this > way, though. My hunch is that EnumSet is usually treated as a bag of named > booleans used as a set of boolean options. The EnumSet is passed around as > an aggregate, with individual enum instances tested at specific points in > the code to adjust the logic. It doesn't seem like the members of an > EnumSet would be iterated frequently, or that it would be useful to have > specific subsets of an EnumSet (which is what NavigableSet would provide). > Maybe similar analysis applies to EnumMap. > > I could be convinced otherwise with use cases, though. > > s'marks > > > On 5/23/23 2:57 AM, Tagir Valeev wrote: > > Hello! > > Looks like this was overlooked. On the other hand, it could even implement > SortedSet or Navigable set, as it's essentially not just ordered but > sorted, according to the enum natural order. Same for EnumMap. > > With best regards, > Tagir Valeev > > On Tue, May 23, 2023, 11:46 Andrey Turbanov <turban...@gmail.com> wrote: > >> Hello. >> I've noticed that EnumSet unfortunately doesn't implement the newly >> introduced interface SequencedSet. >> From the first look it fits into it. >> Is there a reason for that? Sorry if it was already discussed. >> >> Andrey Turbanov >> >
