8358819: The first year is not displayed correctly in Japanese Calendar

[naotoj]

This regression was introduced by the removal of the COMPAT locale provider, which partially broke support for the first year in the Japanese calendar. In the Japanese calendar system, the first year of an era should be formatted using the character "元" rather than the numeral "1". The issue arises from a difference in how pattern character lengths are interpreted between CLDR and SimpleDateFormat. The existing JapaneseEraNameTest has been updated to cover this fix.

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Issue

• JDK-8358819: The first year is not displayed correctly in Japanese Calendar (Bug - P4)

Reviewers

• Justin Lu (@justin-curtis-lu - Committer)
• Joe Wang (@JoeWang-Java - Reviewer)
• Iris Clark (@irisclark - Reviewer)

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[openjdk]

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

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8358819: The first year is not displayed correctly in Japanese Calendar

Reviewed-by: jlu, joehw, iris

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At the time when this comment was updated there had been 25 new commits pushed to the master branch:

• e9216ef: 8358734: Remove JavaTimeSupplementary resource bundles
• e5196fc: 8358764: (sc) SocketChannel.close when thread blocked in read causes connection to be reset (win)
• c98dffa: 8357982: Fix several failing BMI tests with -XX:+UseAPX
• ... and 22 more: https://git.openjdk.org/jdk/compare/156187accc1c3e2a897ced011727a5c8d8e1b0cf...master

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[openjdk]

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[naotoj]

/label remove build

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[mlbridge]

Webrevs

• 00: Full (924a71a9)

[justin-curtis-lu]

OK, I think I understand the general idea. Japanese Imperial Calendar only returns 元 for first year display name when the style is LONG.

// "GanNen" is supported only in the LONG style.
if (field == YEAR
    && (getBaseStyle(style) != LONG || fieldValue != 1 || get(ERA) == 0)) {
    return null;
}

Thus, when SimpleDateFormats rely on the underlying Japanese Calendar, they fetch incorrect results since their CLDR pattern defaults to "y" for LONG and FULL, unlike COMPAT which was "yyyy".

So we are updating the CLDRConverter to adapt the old COMPAT style pattern: "yyyy" when using Japanese calendar for LONG or FULL SimpleDateFormat patterns, such that it can replicate the old "gannen" style which emits the 元.

[naotoj]

So we are updating the CLDRConverter to adapt the old COMPAT style pattern: "yyyy" when using Japanese calendar for LONG or FULL SimpleDateFormat patterns, such that it can replicate the old "gannen" style which emits the 元.

Yes, that’s correct. The patterns used in CLDR, SimpleDateFormat, and DateTimeFormatterBuilder are similar, but there are some differences that can be quite a pain. CLDRConverter tries to handle these differences, but I don’t think it’s entirely accurate. This case falls into that category.

[naotoj]

Thanks for the reviews!
/integrate

[naotoj]

Thanks for the reviews!
/integrate

[openjdk]

Going to push as commit 9982995.
Since your change was applied there have been 47 commits pushed to the master branch:

• 0ef0986: 8359168: Revert stdin.encoding usage in test/hotspot/jtreg/vmTestbase/nsk/jvmti/AttachOnDemand/attach010/attach010Agent00.java
• 610a18e: 8358688: HttpClient: Simplify file streaming in RequestPublishers.FilePublisher
• 8d33ea7: 8354646: java.awt.TextField allows to identify the spaces in a password when double clicked at the starting and end of the text
• ... and 44 more: https://git.openjdk.org/jdk/compare/156187accc1c3e2a897ced011727a5c8d8e1b0cf...master

Your commit was automatically rebased without conflicts.

[openjdk]

@naotoj Pushed as commit 9982995.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[openjdk]

@naotoj The command integrate can only be used in open pull requests.