8306785: fix deficient spliterators for Sequenced Collections

[stuart-marks]

Change some reverse-ordered spliterators to use Spliterators.spliterator(Collection, ORDERED) instead of Spliterators.spliteratorUnknownSize(). This gives SIZED and ORDERED spliterators. More optimizations will be done later. I'm intending to backport this to JDK 21 so I want this to be minimal.

I've also included some adjustments to spliterator implementation comments to clear up a few points of confusion. (No spec changes.)

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Issue

• JDK-8306785: fix deficient spliterators for Sequenced Collections (Bug - P3)

Reviewers

• Paul Sandoz (@PaulSandoz - Reviewer)

Reviewing

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[openjdk]

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[stuart-marks]

@PaulSandoz I'd appreciate your thoughts on the comment changes.

[mlbridge]

Webrevs

• 00: Full (2d51fc11)

[PaulSandoz]

This looks like a reasonable low risk change, plus good clarifications on comments.

[openjdk]

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

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

8306785: fix deficient spliterators for Sequenced Collections

Reviewed-by: psandoz

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At the time when this comment was updated there had been 33 new commits pushed to the master branch:

• 372d0cf: 8311545: Allow test symbol files to be kept in the test image
• 489a32f: 8311813: C1: Uninitialized PhiResolver::_loop field
• 119cc49: 8156889: ListKeychainStore.sh fails in some virtualized environments
• ed9337e: 8155902: DataOuputStream should clarify that it might write primitive types as multiple byte groups
• f82c818: 8308694: Clarify reversed() default methods' implementation requirements
• 7304316: 8311926: java/lang/ScopedValue/StressStackOverflow.java takes 9mins in tier1
• aa7367f: 8311921: Inform about MaxExpectedDataSegmentSize in case of pthread_create failures on AIX
• 753bd56: 8311870: Split CompressedKlassPointers from compressedOops.hpp
• 0b0e064: 8311656: Shenandoah: Unused ShenandoahSATBAndRemarkThreadsClosure::_claim_token
• fd7fddb: 8295894: Remove SECOM certificate that is expiring in September 2023
• ... and 23 more: https://git.openjdk.org/jdk/compare/5667afc36275b064c7700518f453fe8657e13636...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.

[stuart-marks]

/integrate

[openjdk]

Going to push as commit 743e8b8.
Since your change was applied there have been 33 commits pushed to the master branch:

• 372d0cf: 8311545: Allow test symbol files to be kept in the test image
• 489a32f: 8311813: C1: Uninitialized PhiResolver::_loop field
• 119cc49: 8156889: ListKeychainStore.sh fails in some virtualized environments
• ed9337e: 8155902: DataOuputStream should clarify that it might write primitive types as multiple byte groups
• f82c818: 8308694: Clarify reversed() default methods' implementation requirements
• 7304316: 8311926: java/lang/ScopedValue/StressStackOverflow.java takes 9mins in tier1
• aa7367f: 8311921: Inform about MaxExpectedDataSegmentSize in case of pthread_create failures on AIX
• 753bd56: 8311870: Split CompressedKlassPointers from compressedOops.hpp
• 0b0e064: 8311656: Shenandoah: Unused ShenandoahSATBAndRemarkThreadsClosure::_claim_token
• fd7fddb: 8295894: Remove SECOM certificate that is expiring in September 2023
• ... and 23 more: https://git.openjdk.org/jdk/compare/5667afc36275b064c7700518f453fe8657e13636...master

Your commit was automatically rebased without conflicts.

[openjdk]

@stuart-marks Pushed as commit 743e8b8.

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