8358588: ThreadSnapshot.ThreadLock should be static nested class

[shipilev]

SonarCloud points out that ThreadLock class introduced by JDK-8357650 can be turned into static nested class. I don't think this shows any real bug yet, as unreferenced enclosing class reference gets nowhere. But it would be nice to be extra crisp here.

Additional testing:

• Linux x86_64 server fastdebug, serviceability/
• Linux x86_64 server fastdebug, jdk_management

---

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Issue

• JDK-8358588: ThreadSnapshot.ThreadLock should be static nested class (Enhancement - P4)

Reviewers

• Alan Bateman (@AlanBateman - Reviewer)
• Serguei Spitsyn (@sspitsyn - Reviewer)
• Alex Menkov (@alexmenkov - Reviewer)

Reviewing

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[openjdk]

@shipilev This change now passes all automated pre-integration checks.

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After integration, the commit message for the final commit will be:

8358588: ThreadSnapshot.ThreadLock should be static nested class

Reviewed-by: alanb, sspitsyn, amenkov

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At the time when this comment was updated there had been 25 new commits pushed to the master branch:

• 0802348: 8358558: (zipfs) Reorder the listing of "accessMode" property in the ZIP file system's documentation
• 849655a: 8358632: [asan] reports heap-buffer-overflow in AOTCodeCache::copy_bytes
• 575806c: 8358078: javap crashes with NPE on preview class file
• ... and 22 more: https://git.openjdk.org/jdk/compare/7838321b74276e45b92c54904ea31ef70ed9e33f...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

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@shipilev The following label will be automatically applied to this pull request:

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[mlbridge]

Webrevs

• 00: Full (da9a4034)

[AlanBateman]

/label remove core-libs
/label add serviceability

[AlanBateman]

Not an issue but clearer to define it as a static class.

(I've fixed the labels on this PR as this is serviceability code).

[openjdk]

@AlanBateman
The core-libs label was successfully removed.

[openjdk]

@AlanBateman
The serviceability label was successfully added.

[AlanBateman]

The tests in test/jdk/com/sun/management/HotSpotDiagnosticMBean is the quickest way to exercise this code.

[shipilev]

The tests in test/jdk/com/sun/management/HotSpotDiagnosticMBean is the quickest way to exercise this code.

Thanks! I just ran the entire jdk_management test group without any problems.

[shipilev]

Thank you! Here goes.

/integrate

[openjdk]

Going to push as commit dc94900.
Since your change was applied there have been 27 commits pushed to the master branch:

• ace70a6: 8358666: [REDO] Implement JEP 509: JFR CPU-Time Profiling
• 48b97ac: 8358634: RISC-V: Fix several broken documentation web-links
• 0802348: 8358558: (zipfs) Reorder the listing of "accessMode" property in the ZIP file system's documentation
• ... and 24 more: https://git.openjdk.org/jdk/compare/7838321b74276e45b92c54904ea31ef70ed9e33f...master

Your commit was automatically rebased without conflicts.

[openjdk]

@shipilev Pushed as commit dc94900.

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