RFR: 8306647: Implementation of Structured Concurrency (Preview) [v4]

[Daniel Fuchs]

On Thu, 1 Jun 2023 13:43:33 GMT, Alan Bateman <alanb at openjdk.org> wrote:

>> This is the implementation of:
>> 
>> - JEP 453: Structured Concurrency (Preview)
>> - JEP 446: Scoped Values (Preview)
>> 
>> For the most part, this is just moving code and tests.  StructuredTaskScope moves to j.u.concurrent as a preview API, ScopedValue moves to j.lang as a preview API, and module jdk.incubator.concurrent has been removed. The significant API changes since incubator are:
>> 
>> - StructuredTaskScope.fork returns Subtask instead of Future (JEP 453 has a section on this)
>> - ScopedValue.where methods are replaced with runWhere, callWhere and getWhere
>
> Alan Bateman has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 15 commits:
> 
>  - Sync up from loom repo
>  - Merge
>  - Sync with loom repo, re-work ScopedValue class description
>  - Sync up from loom repo
>  - Remove csm.Threads
>  - Merge
>  - Test should not be in update for main line
>  - Sync with loom repo
>  - Sync up tests frmo loom repo
>  - Sync up with loom repo
>  - ... and 5 more: https://git.openjdk.org/jdk/compare/a46b5acc...cc902ce6

I reviewed the API documentation of `ScopedValue` (mostly the class level API documentation, but I had a look at the methods API too) and it looks good. It reads well, and when I had question they were usually answered in the next paragraph that followed what I was reading.

I didn't look at Structured Concurrency.

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Marked as reviewed by dfuchs (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/13932#pullrequestreview-1459172232