RFR: 8366178: Implement JEP 526: Lazy Constants (Second Preview) [v28]

[Jorn Vernee]

On Mon, 17 Nov 2025 11:38:03 GMT, Per Minborg <pminborg at openjdk.org> wrote:

>> Implement JEP 526: Lazy Constants (Second Preview)
>> 
>> The lazy list/map implementations are broken out from `ImmutableCollections` to a separate class.
>> 
>> The old benchmarks are not moved/renamed to allow comparison with previous releases.
>> 
>> `java.util.Optional` is updated so that its field is annotated with `@Stable`.  This is to allow `Optional` instances to be held in lazy constants and still provide constant folding.
>
> Per Minborg has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fix typo

Marked as reviewed by jvernee (Reviewer).

test/jdk/java/lang/LazyConstant/LazyListTest.java line 27:

> 25:  * @summary Basic tests for lazy list methods
> 26:  * @enablePreview
> 27:  * @run junit/othervm --add-opens java.base/java.util=ALL-UNNAMED LazyListTest

I think you can do this with

Suggestion:

 * @modules java.base/java.util:+open
 * @run junit LazyListTest

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PR Review: https://git.openjdk.org/jdk/pull/27605#pullrequestreview-3473667773
PR Review Comment: https://git.openjdk.org/jdk/pull/27605#discussion_r2534826477