RFR: CODETOOLS-7903008: JMH: Support incremental annotation processing for Gradle Java plugin

[Aleksey Shipilev]

On Fri, 6 Aug 2021 07:23:22 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> Please hold off on merging. After running through some more complex benchmark examples, I've found a place where we are not using Filer to write classes. `StateObjectHandler.writeStateOverrides` seems problematic. Looking to see if I can fix that.
>
>> Please hold off on merging. After running through some more complex benchmark examples, I've found a place where we are not using Filer to write classes. `StateObjectHandler.writeStateOverrides` seems problematic. Looking to see if I can fix that.
> 
> I don't see a problem there? `StateObjectHandler.writeStateOverrides` delegates to `GeneratorDestination.newClass`, which in calls `APGeneratorDestination.newClass` in annotation processing mode, which uses `Filer`.

> Sorry to be a bother, but would you mind having another look at this one @shipilev?

Hi! Sorry for delay. This looks marginally okay, although I was getting a bit nervous about implementing new stuff to support (unsupported) Gradle builds. But I think this is okay. 

Now that it affects core code, we have to figure out a bit of testing. Please merge from the `master`, and see if https://github.com/twicksell/jmh/actions have workflows enabled for this PR. Those should be green.

-------------

PR: https://git.openjdk.java.net/jmh/pull/43