<i18n dev> Question about jdk.calendar.japanese.supplemental.era

[Masayoshi Okutsu]

Hi Umaoka-san,

Yes, it's a known problem. I filed a bug report:

https://bugs.openjdk.java.net/browse/JDK-8054214

Thanks,
Masayoshi

On 9/19/2014 8:44 AM, Yoshito Umaoka wrote:
> In July, Okutsu-san sent a review request for JDK-8048123.
> I found this is very useful as temporary workaround until new Java 
> patch embedding the new era.
>
> However, I think I found one issue. If you use java.util.Calendar, 
> with locale ja-JP-u-ca-japanese, it seems to work as you expect. 
> However, with new java.time package, era field prints out integer 
> value of era. Below is an example code which reproduce the issue.
>
> // Pseudo new era
> // 1602288000000L => 2020-10-10 / Heisei 32-10-10
> System.setProperty("jdk.calendar.japanese.supplemental.era",
> "name=新元号,abbr=N,since=1602288000000");
>
> // The day before the switch over
> ChronoLocalDate date = JapaneseDate.of(JapaneseEra.HEISEI, 32, 10, 9);
>
> DateTimeFormatter fmt = 
> DateTimeFormatter.ofLocalizedDate(FormatStyle.FULL)
> .withChronology(JapaneseChronology.INSTANCE).withLocale(Locale.JAPAN);
>
> System.out.println(fmt.format(date)); // Output: "平成32年10月9日"
>
> // Plus one day
> date = date.plus(1, ChronoUnit.DAYS);
>
> System.out.println(fmt.format(date)); // Output: "31年10月10日"
>
>
> The output above becomes "31年10月10日", which is actually composed by 
> Era "3" + Year-Month-Day "1年10月10日".
> So, java.time.format.DateTimeFormatter does not use era name defined 
> in the property, instead, use era's integer value.
>
> In addition to this, the equivalent code with old java.util.Calendar 
> below:
>
> // Pseudo new era
> // 1602288000000L => 2020-10-10 / Heisei 32-10-10
> System.setProperty("jdk.calendar.japanese.supplemental.era",
> "name=新元号,abbr=N,since=1602288000000");
>
> Locale loc = Locale.forLanguageTag("ja-JP-u-ca-japanese");
> Calendar cal = Calendar.getInstance(loc);
> cal.set(32, 10 - 1, 9); // Set October 9, Heisei 32
>
> DateFormat fmt = DateFormat.getDateInstance(DateFormat.FULL, loc);
> System.out.println(fmt.format(cal.getTime())); // Output: 平成32年10月9日
>
> // plus one day
> cal.add(Calendar.DATE, 1);
>
> System.out.println(fmt.format(cal.getTime())); // Output: 新元号元年10 
> 月10日
>
> prints out "元年" (which is correct) instead of "1年" (which is 
> acceptable, but not correct). This is not related to new era switch 
> over actually, but it should be fixed.
>
> Are you aware of these issues?
>
> -Yoshito
>
>