RFR(m): updated: JEP 269 initial API and skeleton implementation (JDK-8139232)

[Michael Hixson]

On Mon, Dec 7, 2015 at 4:19 PM, Stuart Marks <stuart.marks at oracle.com> wrote:
> Hi Maurizio,
>
> Well, maybe we should add five more overloads to EnumSet.of()? (Only
> slightly joking here.)
>
> Setting aside the number of overloads, it would add N more overloads to
> Set.of(). I guess the erasure of <Z extends Enum<Z>> would be Enum, so there
> wouldn't be any overload ambiguity....
>
> To me the question here is whether this adds sufficient value. The advantage
> is that one could write
>
>     Set.of(MyEnum.ONE, MyEnum.TWO, MyEnum.THREE)
>
> instead of
>
>     EnumSet.of(MyEnum.ONE, MyEnum.TWO, MyEnum.THREE)
>
> and get an optimized EnumSet instead of a Set that contains object
> references. Is it worth it?
>
> Presumably this would result in an instance of an immutable EnumSet. Does
> this case come up that often?

Maybe the Guava devs would be willing/able to provide usage stats for
their Sets.immutableEnumSet(...) compared to ImmutableSet.of(...).

-Michael

>
> s'marks
>
>
>
> On 12/4/15 2:22 PM, Maurizio Cimadamore wrote:
>>
>> Hi Stuart
>> small question: I find it a bit odd that EnumSet has max 5 parameters,
>> while Set
>> has more than that.
>>
>> Also, would it be possible, maybe to add overloads to Set that
>> specifically
>> works on Enum constants?
>>
>> <Z extends Enum<Z>> of(Z z1, Z z2) { ... }
>>
>> This would give you a way to call Set.of and get different answers based
>> on the
>> static type of the arguments passed in - and we could deprecate the of
>> method in
>> EnumSet?
>>
>> Too subtle/magic?
>>
>> Maurizio
>>
>> On 02/12/15 02:35, Stuart Marks wrote:
>>>
>>> Hi all,
>>>
>>> Thanks for the previous round of review comments. Here's an updated API
>>> and
>>> implementation for review.
>>>
>>> I've run specdiff with the --hu ("hide unchanged") option, so only the
>>> bits of
>>> the specification that have changed are shown. As before, though, please
>>> ignore the spurious change to EnumSet caused by a javadoc bug.
>>>
>>> API changes:
>>>  - add clarifying notes on immutability
>>>  - remove wording that implied creation of new objects
>>>  - add "value-based" disclaimers
>>>  - add ordering specification for List and non-ordering disclaimers
>>>    for Set and Map
>>>  - clarify that Map.ofEntries() doesn't store the Map.Entry objects,
>>> instead
>>>    it extracts keys and values
>>>  - Map.Entry instances returned from Map.entry() are *not* serializable
>>>
>>> Other:
>>>  - markup cleanups
>>>  - small implementation cleanups
>>>
>>> JEP:
>>>
>>>     http://openjdk.java.net/jeps/269
>>>
>>> API spec (basically List, Map, and Set):
>>>
>>> http://cr.openjdk.java.net/~smarks/reviews/jep269/api.20151201/
>>>
>>> Specdiff:
>>>
>>>
>>>
>>> http://cr.openjdk.java.net/~smarks/reviews/jep269/specdiff.20151201/overview-summary.html
>>>
>>>
>>> Webrev:
>>>
>>> http://cr.openjdk.java.net/~smarks/reviews/jep269/webrev.20151201/
>>>
>>> Thanks,
>>>
>>> s'marks
>>
>>
>