spark-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Aaron Davidson <ilike...@gmail.com>
Subject Re: enum-like types in Spark
Date Mon, 23 Mar 2015 21:09:31 GMT
The only issue I knew of with Java enums was that it does not appear in the
Scala documentation.

On Mon, Mar 23, 2015 at 1:46 PM, Sean Owen <sowen@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 <irashid@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
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message