8362123: ClassLoader Leak via Executors.newSingleThreadExecutor(...)

[chrisdennis]

This is a backport of d5a207994b9c374e6638e57826326f8f4593b96b from openjdk/jdk which is a bug-fix of JDK-8362123.

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8362123 needs maintainer approval

Issue

• JDK-8362123: ClassLoader Leak via Executors.newSingleThreadExecutor(...) (Bug - P4 - Requested)

Reviewing

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$ git checkout pull/2346

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$ git pull https://git.openjdk.org/jdk21u-dev.git pull/2346/head

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[bridgekeeper]

👋 Welcome back chrisdennis! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

⚠️ @chrisdennis This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (e09d980b)

[chrisdennis]

/approval request This fixes a memory leak and/or prompt garbage collection issue introduced in Java 21

[openjdk]

@chrisdennis
8362123: The approval request has been created successfully.

[GoeLin]

Hi @chrisdennis
I am not sure this is a good backport as it adds a public method. Do we need a CSR?
Also, if this was introduced in 21, can you please point out the change that did this and link it as "caused by"?
Thanks.

[chrisdennis]

This isn't adding a new public (API) method it's just adding a missing override of an existing public method in a private static inner class of Executors.

The bug was introduced when the Executors.newSingleThreadExecutor(...) moved from a finalize() based approach for last chance cleanup to a Cleaner based one. The commit that introduced it was therefore 2e78d83 (JDK-8302899). Unfortunately, I don't think I can create a link reflecting this as I lack direct JBS access due to being only a Contributor.