On my JDK-6-installation I can reproduce your problem:
Date jud = new SimpleDateFormat("yyyy-MM-dd").parse("2014-02-28");
String month =
DateFormat.getDateInstance(SimpleDateFormat.LONG, new Locale("ru")).format(jud);
System.out.println(month); // output: 28 Февраль 2014 г.
Java-8 offers you a solution.
It seems that the JDK has changed the internal default from "standalone-style" (nominative) to "format-style" (genitive).
String date =
DateTimeFormatter.ofLocalizedDate(FormatStyle.FULL)
.withLocale(new Locale("ru"))
.format(LocalDate.of(2014, 2, 28));
System.out.println(date); // output: 28 февраля 2014 г.
If you need to apply standalone textstyle then you have to set up your own DateTimeFormatterBuilder
which requires a little bit more effort, else TextStyle.FULL
should be the default.
String m = Month.FEBRUARY.getDisplayName(TextStyle.FULL , new Locale("ru"));
// февраля (first and last char are different)
String s = Month.FEBRUARY.getDisplayName(TextStyle.FULL_STANDALONE , new Locale("ru"));
// Февраль (this style can be used in DateTimeFormatterBuilder for the month field, too)
Workaround for Java-pre-8 using old style:
Define your own text resources (troublesome)!
Locale russian = new Locale("ru");
String[] newMonths = {
"января", "февраля", "марта", "апреля", "мая", "июня",
"июля", "августа", "сентября", "октября", "ноября", "декабря"};
DateFormatSymbols dfs = DateFormatSymbols.getInstance(russian);
dfs.setMonths(newMonths);
DateFormat df = DateFormat.getDateInstance(DateFormat.LONG, russian);
SimpleDateFormat sdf = (SimpleDateFormat) df;
sdf.setDateFormatSymbols(dfs);
Date jud = new SimpleDateFormat("yyyy-MM-dd").parse("2014-02-28");
String month = sdf.format(jud);
System.out.println(month); // output: 28 февраля 2014 г.
Joda-Time does not offer a good solution in a Java-pre-8 environment because it only delegates to JDK. See also a similar issue on Joda-site.
Finally there is also my library Time4J which can solve the problem like Java-8, but uses its own text resources for Russian and understands both forms (old style and standalone-style), so this is a simple solution for older Java-versions (and will of course not be obsoleted by Java-8 due to many other feature enhancements).
System.out.println(
ChronoFormatter.ofDateStyle(DisplayMode.FULL, new Locale("ru")).format(
PlainDate.of(2014, Month.FEBRUARY, 28)
)
); // output: 28 февраля 2014 г.