<i18n dev> RFR: 8366178: Implement JEP 526: Lazy Constants (Second Preview) [v12]

[Maurizio Cimadamore]

On Fri, 17 Oct 2025 09:25:01 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:
> 
>   Update javadocs

src/java.base/share/classes/java/lang/LazyConstant.java line 54:

> 52:  * again upon subsequent {@linkplain #get() get} invocations.
> 53:  * <p>
> 54:  * A lazy constant is <em>shallowly immutable</em>, meaning the reference to the contents

This para here seems a bit redundant. In part it repeats something already said (when initialized, contents will never change). I'd drop this from here, and maybe push it down to an API note (e.g. note: the contents of a lazy constant can be mutable -- e.g. an ArrayList).

src/java.base/share/classes/java/lang/LazyConstant.java line 60:

> 58:  * <p>
> 59:  * Consider the following example where a lazy constant field "{@code logger}" is a
> 60:  * shallowly immutable holder of an object of type {@code Logger}:

"where the lazy constant field "logger" holds an object of type Logger"

src/java.base/share/classes/java/lang/LazyConstant.java line 77:

> 75:  *}
> 76:  * <p>
> 77:  * Initially, the lazy constant (and its contents) is <em>not initialized</em>.

Suggestion:

 * Initially, the lazy constant is <em>not initialized</em>.

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PR Review Comment: https://git.openjdk.org/jdk/pull/27605#discussion_r2439072055
PR Review Comment: https://git.openjdk.org/jdk/pull/27605#discussion_r2439073774
PR Review Comment: https://git.openjdk.org/jdk/pull/27605#discussion_r2439075865