8334742: Change java.time month/day field types to 'byte'

[gauthamkrishnanibm]

In the following classes, month and day values are stored in fields of type 'int' or 'short'. The range of allowed values is small enough that the type can be 'byte' instead.

java.time.YearMonth
java.time.MonthDay
java.time.LocalDate
java.time.chono.HijrahDate

Refactoring the type will give the JVM a little more layout flexibility, and will be especially useful when these classes become value classes.

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Progress

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Issue

• JDK-8334742: Change java.time month/day field types to 'byte' (Bug - P4)

Reviewers

• Roger Riggs (@RogerRiggs - Reviewer)

Reviewing

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[openjdk]

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

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8334742: Change java.time month/day field types to 'byte'

Reviewed-by: rriggs

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At the time when this comment was updated there had been 478 new commits pushed to the master branch:

• e3f85c9: 8355003: Implement JEP 515: Ahead-of-Time Method Profiling
• 63d0e7f: 8355725: SPEC_FILTER stopped working
• a4f870d: 8357510: [REDO] RunTest variables should always be assigned
• ... and 475 more: https://git.openjdk.org/jdk/compare/bccf057fa4a0208bda55d2972d0161044f050ea5...master

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[openjdk]

@gauthamkrishnanibm The following labels will be automatically applied to this pull request:

• core-libs
• i18n

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[mlbridge]

Webrevs

• 01: Full - Incremental (148c3834)
• 00: Full (e198afb2)

[naotoj]

Since they are serialized fields (except Hijrah ones), I don't think this is doable.

[gauthamkrishnanibm]

@naotoj Thanks for reviewing.

You are right.
But when I checked these classes use a custom Externalizable encoding (see 'readExternal'/'writeExternal'), which already stores these values as bytes.

[naotoj]

But when I checked these classes use a custom Externalizable encoding (see 'readExternal'/'writeExternal'), which already stores these values as bytes.

Sorry, that is correct. Jumped the gun too soon

[RogerRiggs]

Its recommended to set the assignee of a issue before starting working and to mark it in progress.
@gauthamkrishnanibm Please make the necessary changes to the issue to let people know you are working on it.

[gauthamkrishnanibm]

@RogerRiggs
Sorry. I am not having write access to JBS as I just started contributing.
Should I discuss about the change in mailing list ?

[RogerRiggs]

I hope you've found The OpenJDK Developers' Guide, its a good read to know what to expect and what is expected of contributors.
Feel free to ask on the mail alias about how things work. If you found the issue you would have seen it was already assigned and it would be appropriate to ask.

Please continue.
As with any modification, its important to identify the tests that validate the change. In this case, the tests are in the repo under test/jdk/java/time.

[RogerRiggs]

Passed CI tier 1-3.

[RogerRiggs]

Looks good

[openjdk]

⚠️ @gauthamkrishnanibm the full name on your profile does not match the author name in this pull requests' HEAD commit. If this pull request gets integrated then the author name from this pull requests' HEAD commit will be used for the resulting commit. If you wish to push a new commit with a different author name, then please run the following commands in a local repository of your personal fork:

$ git checkout JDK-8334742
$ git commit --author='Preferred Full Name <[email protected]>' --allow-empty -m 'Update full name'
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[gauthamkrishnanibm]

/integrate

[openjdk]

@gauthamkrishnanibm
Your change (at version 148c383) is now ready to be sponsored by a Committer.

[RogerRiggs]

/sponsor

[openjdk]

Going to push as commit 4ced4e7.
Since your change was applied there have been 478 commits pushed to the master branch:

• e3f85c9: 8355003: Implement JEP 515: Ahead-of-Time Method Profiling
• 63d0e7f: 8355725: SPEC_FILTER stopped working
• a4f870d: 8357510: [REDO] RunTest variables should always be assigned
• ... and 475 more: https://git.openjdk.org/jdk/compare/bccf057fa4a0208bda55d2972d0161044f050ea5...master

Your commit was automatically rebased without conflicts.

[openjdk]

@RogerRiggs @gauthamkrishnanibm Pushed as commit 4ced4e7.

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