8327046: (fs) Files.walk should be clear that depth-first traversal is pre-order

[pavelrappo]

Please review this clarification to the specification of the two overloads of java.nio.file.Files.walk. No tests are added, as I believe the existing StreamTest.testWalk* methods already test the order sufficiently. I also took this opportunity to fix a few minor typos.

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Issue

• JDK-8327046: (fs) Files.walk should be clear that depth-first traversal is pre-order (Bug - P4)

Reviewers

• Alan Bateman (@AlanBateman - Reviewer) ⚠️ Review applies to 5ffccf38
• Guoxiong Li (@lgxbslgx - Committer)

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• 03: Full - Incremental (75d1cd01)
• 02: Full - Incremental (5ffccf38)
• 01: Full - Incremental (4240524b)
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[AlanBateman]

Your proposed wording is okay but it makes me wonder if we now need to define "pre-order" as it is new term here. An alternative is something like this:

"The file tree traversal is depth-first with a directory visited before the entries in the directory."

which will align it closely to the existing wording in walkFileTree and FileVisitor.

[pavelrappo]

You are right. Although in-order, pre-order and post-order are all well-known terms, there are no occurrences of them in the java.base API documentation. Fixed closely to what you proposed; please examine 5ffccf3.

[openjdk]

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

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

8327046: (fs) Files.walk should be clear that depth-first traversal is pre-order

Reviewed-by: alanb, gli

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At the time when this comment was updated there had been 13 new commits pushed to the master branch:

• a065eba: 8326496: [test] checkHsErrFileContent support printing hserr in error case
• 0899b3b: 8326612: Parallel: remove redundant assertion from ScavengeRootsTask
• 12404a5: 8324790: ifnode::fold_compares_helper cleanup
• 0d35450: 8327040: Problemlist ActionListenerCalledTwiceTest.java test failing in macos14
• 8d6f784: 8327056: Remove unused static char array in JvmtiAgentList::lookup
• 43af120: 8326959: Improve JVMCI option help
• 742c776: 8322743: C2: prevent lock region elimination in OSR compilation
• d29cefb: 8326838: JFR: Native mirror events
• b8fc418: 8326525: com/sun/tools/attach/BasicTests.java does not verify AgentLoadException case
• d9aa1de: 8318605: Enable parallelism in vmTestbase/nsk/stress/stack tests
• ... and 3 more: https://git.openjdk.org/jdk/compare/430290066c23d09166a84f2f6f89e770c6ba04ff...master

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[lgxbslgx]

A trivial issue about the name.

[lgxbslgx]

Looks good.

[pavelrappo]

/integrate

[openjdk]

Going to push as commit 012411a.
Since your change was applied there have been 19 commits pushed to the master branch:

• 98434d6: 8322170: Update deprecated/obsolete/expired flags table for GC
• c02e7f4: 8327058: RISC-V: make Zcb experimental
• b972997: 8326974: ODR violation in macroAssembler_aarch64.cpp
• 437cf35: 8319648: java/lang/SecurityManager tests ignore vm flags
• e85265a: 8325361: Make sun.net.www.MessageHeader final
• 5b75199: 8327022: Parallel: Remove experimental dense prefix calculation
• a065eba: 8326496: [test] checkHsErrFileContent support printing hserr in error case
• 0899b3b: 8326612: Parallel: remove redundant assertion from ScavengeRootsTask
• 12404a5: 8324790: ifnode::fold_compares_helper cleanup
• 0d35450: 8327040: Problemlist ActionListenerCalledTwiceTest.java test failing in macos14
• ... and 9 more: https://git.openjdk.org/jdk/compare/430290066c23d09166a84f2f6f89e770c6ba04ff...master

Your commit was automatically rebased without conflicts.

[openjdk]

@pavelrappo Pushed as commit 012411a.

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