On Tue, 21 Feb 2023 18:24:05 GMT, Alan Bateman <al...@openjdk.org> wrote:
>> Executors.newSingleThreadExecutor returns a delegating ExecutorService that
>> has finalizer to shutdown the underlying TPE when the wrapper is
>> finalizable. It goes back to JDK 6 and JDK-6399443. This is the last
>> non-empty finalizer in java.base. Removing it will likely lead to bug
>> reports/complaints as the current behavior goes back to 2006. So the
>> proposal is to just replace it with a Cleaner, trivially done in this case.
>> As part of the changes, I've replaced the existing test with a more modern
>> test that exercises more scenarios.
>
> Alan Bateman has updated the pull request incrementally with one additional
> commit since the last revision:
>
> Fix typo in comment, remove blank line
src/java.base/share/classes/java/util/concurrent/Executors.java line 837:
> 835: }
> 836: }
> 837:
You might consider keeping a dedicated subclass
("CleanableDelegatedExecutorService"?). Such a class could save the Cleanable
from Cleaner.register(), and override the shutdown() method to call
Cleanable.clean(). This would reduce GC reference tracking, for instance in
places where newSingleThreadExecutor() is used in a try-with-resources.
-------------
PR: https://git.openjdk.org/jdk/pull/12675
