I am reviving an old thread here. The link for the example code for the java enum based solution is now dead: would someone please post an updated link showing the proper interop?
Specifically: it is my understanding that java enum's may not be created within Scala. So is the proposed solution requiring dropping out into Java to create the enum's? 2015-04-09 17:16 GMT-07:00 Xiangrui Meng <men...@gmail.com>: > Using Java enums sound good. We can list the values in the JavaDoc and > hope Scala will be able to correctly generate docs for Java enums in > the future. -Xiangrui > > On Thu, Apr 9, 2015 at 10:59 AM, Imran Rashid <iras...@cloudera.com> > wrote: > > any update here? This is relevant for a currently open PR of mine -- > I've > > got a bunch of new public constants defined w/ format #4, but I'd gladly > > switch to java enums. (Even if we are just going to postpone this > decision, > > I'm still inclined to switch to java enums ...) > > > > just to be clear about the existing problem with enums & scaladoc: right > > now, the scaladoc knows about the enum class, and generates a page for > it, > > but it does not display the enum constants. It is at least labeled as a > > java enum, though, so a savvy user could switch to the javadocs to see > the > > constants. > > > > > > > > On Mon, Mar 23, 2015 at 4:50 PM, Imran Rashid <iras...@cloudera.com> > wrote: > >> > >> well, perhaps I overstated things a little, I wouldn't call it the > >> "official" solution, just a recommendation in the never-ending debate > (and > >> the recommendation from folks with their hands on scala itself). > >> > >> Even if we do get this fixed in scaladoc eventually -- as its not in the > >> current versions, where does that leave this proposal? personally I'd > >> *still* prefer java enums, even if it doesn't get into scaladoc. btw, > even > >> with sealed traits, the scaladoc still isn't great -- you don't see the > >> values from the class, you only see them listed from the companion > object. > >> (though, that is somewhat standard for scaladoc, so maybe I'm reaching a > >> little) > >> > >> > >> > >> On Mon, Mar 23, 2015 at 4:11 PM, Patrick Wendell <pwend...@gmail.com> > >> wrote: > >>> > >>> If the official solution from the Scala community is to use Java > >>> enums, then it seems strange they aren't generated in scaldoc? Maybe > >>> we can just fix that w/ Typesafe's help and then we can use them. > >>> > >>> On Mon, Mar 23, 2015 at 1:46 PM, Sean Owen <so...@cloudera.com> wrote: > >>> > Yeah the fully realized #4, which gets back the ability to use it in > >>> > switch statements (? in Scala but not Java?) does end up being kind > of > >>> > huge. > >>> > > >>> > I confess I'm swayed a bit back to Java enums, seeing what it > >>> > involves. The hashCode() issue can be 'solved' with the hash of the > >>> > String representation. > >>> > > >>> > On Mon, Mar 23, 2015 at 8:33 PM, Imran Rashid <iras...@cloudera.com> > >>> > wrote: > >>> >> I've just switched some of my code over to the new format, and I > just > >>> >> want > >>> >> to make sure everyone realizes what we are getting into. I went > from > >>> >> 10 > >>> >> lines as java enums > >>> >> > >>> >> > >>> >> > https://github.com/squito/spark/blob/fef66058612ebf225e58dd5f5fea6bae1afd5b31/core/src/main/java/org/apache/spark/status/api/StageStatus.java#L20 > >>> >> > >>> >> to 30 lines with the new format: > >>> >> > >>> >> > >>> >> > https://github.com/squito/spark/blob/SPARK-3454_w_jersey/core/src/main/scala/org/apache/spark/status/api/v1/api.scala#L250 > >>> >> > >>> >> its not just that its verbose. each name has to be repeated 4 > times, > >>> >> with > >>> >> potential typos in some locations that won't be caught by the > >>> >> compiler. > >>> >> Also, you have to manually maintain the "values" as you update the > set > >>> >> of > >>> >> enums, the compiler won't do it for you. > >>> >> > >>> >> The only downside I've heard for java enums is enum.hashcode(). > OTOH, > >>> >> the > >>> >> downsides for this version are: maintainability / verbosity, no > >>> >> values(), > >>> >> more cumbersome to use from java, no enum map / enumset. > >>> >> > >>> >> I did put together a little util to at least get back the equivalent > >>> >> of > >>> >> enum.valueOf() with this format > >>> >> > >>> >> > >>> >> > https://github.com/squito/spark/blob/SPARK-3454_w_jersey/core/src/main/scala/org/apache/spark/util/SparkEnum.scala > >>> >> > >>> >> I'm not trying to prevent us from moving forward on this, its fine > if > >>> >> this > >>> >> is still what everyone wants, but I feel pretty strongly java enums > >>> >> make > >>> >> more sense. > >>> >> > >>> >> thanks, > >>> >> Imran > >>> > > >>> > --------------------------------------------------------------------- > >>> > To unsubscribe, e-mail: dev-unsubscr...@spark.apache.org > >>> > For additional commands, e-mail: dev-h...@spark.apache.org > >>> > > >> > >> > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@spark.apache.org > For additional commands, e-mail: dev-h...@spark.apache.org > >
