8309196: Remove Thread.countStackFrames

[AlanBateman]

Thread.countStackFrames is/was an ill-defined method that dates from JDK 1.0 for counting the stack frames of a suspended Thread. The method was deprecated in JDK 1.2 (1998), deprecated for removal in Java 9, and re-specified/degraded to throw UOE unconditionally in Java 14. Java 22 would be a fine time to finally remove this method.

Code that wants to count stack frames should be directed to use j.l.StackWalker, or if a tool, then it can use JVM TI and other tool APIs.

A corpus analysis of 30M classes in 131k artifacts from Maven Central found only 1 usages to this method. The 1 usage appears to be a class that just wraps all methods, it doesn't actually make use of it.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change requires CSR request JDK-8309201 to be approved

Issues

• JDK-8309196: Remove Thread.countStackFrames (Enhancement - P4)
• JDK-8309201: Remove Thread.countStackFrames (CSR)

Reviewers

• Roger Riggs (@RogerRiggs - Reviewer)
• Mandy Chung (@mlchung - Reviewer)
• David Holmes (@dholmes-ora - Reviewer)
• Jaikiran Pai (@jaikiran - Reviewer)
• Iris Clark (@irisclark - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/14257/head:pull/14257
$ git checkout pull/14257

Update a local copy of the PR:
$ git checkout pull/14257
$ git pull https://git.openjdk.org/jdk.git pull/14257/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 14257

View PR using the GUI difftool:
$ git pr show -t 14257

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/14257.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back alanb! 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]

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

• core-libs

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[AlanBateman]

/csr

[openjdk]

@AlanBateman has indicated that a compatibility and specification (CSR) request is needed for this pull request.

@AlanBateman please create a CSR request for issue JDK-8309196 with the correct fix version. This pull request cannot be integrated until the CSR request is approved.

[mlbridge]

Webrevs

• 02: Full - Incremental (b784ff83)
• 01: Full - Incremental (e44c3c49)
• 00: Full (36138f34)

[RogerRiggs]

Looks good.

[dholmes-ora]

Yes :)

[irisclark]

Happy to see this being removed early in JDK 22!

[openjdk]

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

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

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

8309196: Remove Thread.countStackFrames

Reviewed-by: rriggs, mchung, dholmes, jpai, iris

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been no new commits pushed to the master branch. If another commit should be pushed before you perform the /integrate command, your PR will be automatically rebased. If you prefer to avoid any potential automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[AlanBateman]

/integrate

[openjdk]

Going to push as commit b2a5271.

[openjdk]

@AlanBateman Pushed as commit b2a5271.

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