8214248: (fs) Files:mismatch spec clarifications

[bplb]

Clarify that Files::mismatch does not access the file system if both paths locate the same file. Add package documentation about file operations on directories being implementation specific.

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• Change requires CSR request JDK-8314682 to be approved

Issues

• JDK-8214248: (fs) Files:mismatch spec clarifications (Enhancement - P3)
• JDK-8314682: (fs) Files:mismatch spec clarifications (CSR)

Reviewers

• Alan Bateman (@AlanBateman - Reviewer)

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[AlanBateman]

I'm not sure about this wording or section title. I think the point is that a file path can locate any time of file, be it a regular file, directory, sym link, or something else. There is nothing to prevent attempting a file operation on any file but it may be that some operations aren't applicable or supported on some file types. It may be that this part should be a separate issue/PR as it's nothing to do with Files.mismatch.

[openjdk]

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

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

8214248: (fs) Files:mismatch spec clarifications

Reviewed-by: alanb

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 45 new commits pushed to the master branch:

• ce1ded1: 8314749: Remove unimplemented _Copy_conjoint_oops_atomic
• 32bf468: 8314274: G1: Fix -Wconversion warnings around G1CardSetArray::_data
• eb06572: 8313408: Use SVG for BoxLayout example
• 20e9478: 8314426: runtime/os/TestTrimNative.java is failing on slow machines
• 69d900d: 8314730: GHA: Drop libfreetype6-dev transitional package in favor of libfreetype-dev
• f39fc0a: 8314738: Remove all occurrences of and support for @Revised
• 6b9df03: 8311240: Eliminate usage of testcases.jar from TestMetaSpaceLog.java
• 3e1b1bf: 8314688: VM build without C1 fails after JDK-8313372
• 02ef859: 8313689: C2: compiler/c2/irTests/scalarReplacement/AllocationMergesTests.java fails intermittently with -XX:-TieredCompilation
• ab86d23: 8250269: Replace ATTRIBUTE_ALIGNED with alignas
• ... and 35 more: https://git.openjdk.org/jdk/compare/62ca00158c7ce7b40b5910562c1857b9f05ddf9f...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.

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

[bplb]

/integrate

[openjdk]

Going to push as commit 2eae13c.
Since your change was applied there have been 45 commits pushed to the master branch:

• ce1ded1: 8314749: Remove unimplemented _Copy_conjoint_oops_atomic
• 32bf468: 8314274: G1: Fix -Wconversion warnings around G1CardSetArray::_data
• eb06572: 8313408: Use SVG for BoxLayout example
• 20e9478: 8314426: runtime/os/TestTrimNative.java is failing on slow machines
• 69d900d: 8314730: GHA: Drop libfreetype6-dev transitional package in favor of libfreetype-dev
• f39fc0a: 8314738: Remove all occurrences of and support for @Revised
• 6b9df03: 8311240: Eliminate usage of testcases.jar from TestMetaSpaceLog.java
• 3e1b1bf: 8314688: VM build without C1 fails after JDK-8313372
• 02ef859: 8313689: C2: compiler/c2/irTests/scalarReplacement/AllocationMergesTests.java fails intermittently with -XX:-TieredCompilation
• ab86d23: 8250269: Replace ATTRIBUTE_ALIGNED with alignas
• ... and 35 more: https://git.openjdk.org/jdk/compare/62ca00158c7ce7b40b5910562c1857b9f05ddf9f...master

Your commit was automatically rebased without conflicts.

[openjdk]

@bplb Pushed as commit 2eae13c.

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