<i18n dev> RFR: 8347955: TimeZone methods to stream the available timezone IDs [v2]

[Justin Lu]

On Thu, 23 Jan 2025 17:41:35 GMT, Naoto Sato <naoto at openjdk.org> wrote:

>> Justin Lu has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   reflect Naoto's review
>
> src/java.base/share/classes/java/util/TimeZone.java line 652:
> 
>> 650:      *
>> 651:      * @param rawOffset the given time zone GMT offset in milliseconds.
>> 652:      * @return an array of IDs, where the time zone for that ID has
> 
> array -> stream

Thanks for the catch. Fixed this and bumped those Zone* file copyright years in https://github.com/openjdk/jdk/pull/23251/commits/48956fdd92aba3a3802e81cfbc8468296dbab777. I double checked that all the test files have 2025 copyright years.

> src/java.base/share/classes/sun/util/calendar/ZoneInfoFile.java line 96:
> 
>> 94:         // specify it. Keep the same behavior for better
>> 95:         // compatibility.
>> 96:         String[] list = ids.toArray(new String[0]);
> 
> Why is this change? Since the array has correct size, no extra array allocation is needed?

Regarding the switch from `toArray(new T[size])` to `toArray(new T[0])`, based off https://shipilev.net/blog/2016/arrays-wisdom-ancients/#_conclusion, the JVM performs the latter faster. I believe the article data/results still hold true now.

> src/java.base/share/classes/sun/util/calendar/ZoneInfoFile.java line 122:
> 
>> 120:         return zoneIds()
>> 121:                 .filter(id -> getZoneInfo(id).getRawOffset() == rawOffset)
>> 122:                 .sorted(); // Sort the IDs, see getZoneIds(int)
> 
> This is interesting. one with `rawOffset` is soreted, but the other is not. It is inconsistent but probably we should align as you did here.

Noticed that too. There is also the argument that since these stream methods are new, we can leave it un-sorted but we would have to specify the deviation. Although I agree it is best to align for consistency.

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PR Review Comment: https://git.openjdk.org/jdk/pull/23251#discussion_r1927539888
PR Review Comment: https://git.openjdk.org/jdk/pull/23251#discussion_r1927539958
PR Review Comment: https://git.openjdk.org/jdk/pull/23251#discussion_r1927540008