Locale languageTag anomaly

[Naoto Sato]

Hi Jon,

JDK historically represents Norwegian Nynorsk language with no_NO_NY 
(JDK unique "NY" variant), because it predates the ISO 639-1:2002 
standard which introduced "nn" as the language code for Nynorsk. This 
legacy JDK locale is converted to BCP47 compliant language tag using 
"nn" language code.

Locale.toLanguageTag() has the following sentence for this:

---
A locale with language "no", country "NO", and variant "NY", 
representing Norwegian Nynorsk (Norway), is converted to a language tag 
"nn-NO".
---

So in short, that is the expected behavior.

Naoto

On 6/7/18 2:19 PM, Jonathan Gibbons wrote:
> Regarding Locale.toLanguageTag, Locale.forLanguageTag
> 
> Should I be surprised (i.e. is it a bug) that out of 736 installed 
> locales in a standard build of JDK, exactly 1 locale fails the following 
> round-trip test:
> 
>      locale.equals(Locale.forLanguageTag(locale.toLanguageTag()))
> 
> The locale "no_NO_NY" comes back as "nn_NO".
> 
> Attached is a test program.  Here is the output from the test program:
> 
> $ /opt/jdk/1.9.0/bin/java -cp play/locales/classes Locales
> test locale: no_NO_NY [no,NO,NY] nn-NO
>       forLanguageTag: nn_NO
> Tested 736 locales
> Mismatch 1 locales
> 
> -- Jon