<i18n dev> RFR: 8369452: Locale.Builder.setLanguageTag(String) does not clear on empty or null String

[Naoto Sato]

On Thu, 9 Oct 2025 18:12:58 GMT, Justin Lu <jlu at openjdk.org> wrote:

> Please review this PR which corrects the behavior of `Locale.Builder.setLanguageTag(String)` on the null and empty String case.
> 
> This method is specified as follows,
> 
>> Null and the empty string cause the builder to be reset
> 
> Currently, NPE is thrown for a null tag, and ILE is thrown for an empty String. They are both corrected to not throw, and instead reset the state of the `Locale.Builder`.

LGTM

test/jdk/java/util/Locale/LocaleEnhanceTest.java line 779:

> 777:         bldr.setLanguageTag("en-US");
> 778:         assertDoesNotThrow(() -> bldr.setLanguageTag(tag));
> 779:         assertEquals(tag + " did not clear the builder", empty.build(), bldr.build());

Should not happen, but if empty string caused an assertion failure, the error message starts with " did not clear..."

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Marked as reviewed by naoto (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/27734#pullrequestreview-3320916918
PR Review Comment: https://git.openjdk.org/jdk/pull/27734#discussion_r2418168857