RFR: 7903596: JMH: Explicitly enable annotation processors [v2]

[Aleksey Shipilev]

On Tue, 8 Oct 2024 07:29:31 GMT, Jaikiran Pai <jpai at openjdk.org> wrote:

>> Can I please get a review of this change which proposes to address the issue noted in https://bugs.openjdk.org/browse/CODETOOLS-7903596?
>> 
>> As noted in that issue, when a benchmark generated using Java 22 is run, at runtime it fails with:
>> 
>> 
>> java -jar target/benchmarks.jar
>> Exception in thread "main" java.lang.RuntimeException: ERROR: Unable to find the resource: /META-INF/BenchmarkList
>> 	at org.openjdk.jmh.runner.AbstractResourceReader.getReaders(AbstractResourceReader.java:98)
>> 	at org.openjdk.jmh.runner.BenchmarkList.find(BenchmarkList.java:124)
>> 	at org.openjdk.jmh.runner.Runner.internalRun(Runner.java:252)
>> 	at org.openjdk.jmh.runner.Runner.run(Runner.java:208)
>> 	at org.openjdk.jmh.Main.main(Main.java:71)
>> 
>> 
>> This is due to annotation processors being disabled by default during compilation starting Java 22. The commit in this PR, explicitly enables the `org.openjdk.jmh.generators.BenchmarkProcessor` annotation processor to allow for it to generate the necessary benchmark resources.
>> 
>> I've tested this change locally, with Java 8, Java 21 as well as Java 22 and the newly generated benchmark is now functional on all these versions.
>
> Jaikiran Pai has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:
> 
>  - merge latest from master branch
>  - 7903596: jmh-java-benchmark-archetype generated benchmark fails at runtime - ERROR: Unable to find the resource: /META-INF/BenchmarkList

All right, I think this is what we minimally need to be able to build and test on JDK 23: [jmh-jdk23-1.patch](https://github.com/user-attachments/files/18028639/jmh-jdk23-1.patch).

@sigpwned -- `jmh-ct-tests` are weird in the sense they use their own in-memory compiler, so adding things to POM would not work :) It is also why they are compiled with `-proc:none`. See the patch above where the in-memory compiler options are added. Good call on using `<annotationProcessors>` in POMs, though, it is a bit cleaner.

@jaikiran, please mix it in this PR, or shout if you don't have time to complete this PR, and I'll take over.

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PR Comment: https://git.openjdk.org/jmh/pull/125#issuecomment-2521231778