JapaneseChronology

public final class JapaneseChronology
extends AbstractChronology implements Serializable

java.lang.Object
   ↳ java.time.chrono.AbstractChronology
     ↳ java.time.chrono.JapaneseChronology


The Japanese Imperial calendar system.

This chronology defines the rules of the Japanese Imperial calendar system. This calendar system is primarily used in Japan. The Japanese Imperial calendar system is the same as the ISO calendar system apart from the era-based year numbering.

Japan introduced the Gregorian calendar starting with Meiji 6. Only Meiji and later eras are supported; dates before Meiji 6, January 1 are not supported.

The supported ChronoField instances are:

  • DAY_OF_WEEK
  • DAY_OF_MONTH
  • DAY_OF_YEAR
  • EPOCH_DAY
  • MONTH_OF_YEAR
  • PROLEPTIC_MONTH
  • YEAR_OF_ERA
  • YEAR
  • ERA

Summary

Fields

public static final JapaneseChronology INSTANCE

Singleton instance for Japanese chronology.

Public methods

JapaneseDate date(int prolepticYear, int month, int dayOfMonth)

Obtains a local date in Japanese calendar system from the proleptic-year, month-of-year and day-of-month fields.

JapaneseDate date(Era era, int yearOfEra, int month, int dayOfMonth)

Obtains a local date in Japanese calendar system from the era, year-of-era, month-of-year and day-of-month fields.

JapaneseDate date(TemporalAccessor temporal)
JapaneseDate dateEpochDay(long epochDay)

Obtains a local date in the Japanese calendar system from the epoch-day.

JapaneseDate dateNow(ZoneId zone)
JapaneseDate dateNow()
JapaneseDate dateNow(Clock clock)
JapaneseDate dateYearDay(Era era, int yearOfEra, int dayOfYear)

Obtains a local date in Japanese calendar system from the era, year-of-era and day-of-year fields.

JapaneseDate dateYearDay(int prolepticYear, int dayOfYear)

Obtains a local date in Japanese calendar system from the proleptic-year and day-of-year fields.

JapaneseEra eraOf(int eraValue)

Returns the calendar system era object from the given numeric value.

List<Era> eras()
String getCalendarType()

Gets the calendar type of the underlying calendar system - 'japanese'.

String getId()

Gets the ID of the chronology - 'Japanese'.

boolean isLeapYear(long prolepticYear)

Checks if the specified year is a leap year.

ChronoLocalDateTime<JapaneseDate> localDateTime(TemporalAccessor temporal)
int prolepticYear(Era era, int yearOfEra)
ValueRange range(ChronoField field)
JapaneseDate resolveDate(Map<TemporalFieldLong> fieldValues, ResolverStyle resolverStyle)

Resolves parsed ChronoField values into a date during parsing.

ChronoZonedDateTime<JapaneseDate> zonedDateTime(TemporalAccessor temporal)
ChronoZonedDateTime<JapaneseDate> zonedDateTime(Instant instant, ZoneId zone)

Inherited methods

Fields

INSTANCE

Added in API level 26
public static final JapaneseChronology INSTANCE

Singleton instance for Japanese chronology.

Public methods

date

Added in API level 26
public JapaneseDate date (int prolepticYear, 
                int month, 
                int dayOfMonth)

Obtains a local date in Japanese calendar system from the proleptic-year, month-of-year and day-of-month fields.

The Japanese proleptic year, month and day-of-month are the same as those in the ISO calendar system. They are not reset when the era changes.

Parameters
prolepticYear int: the proleptic-year

month int: the month-of-year

dayOfMonth int: the day-of-month

Returns
JapaneseDate the Japanese local date, not null

Throws
DateTimeException if unable to create the date

date

Added in API level 26
public JapaneseDate date (Era era, 
                int yearOfEra, 
                int month, 
                int dayOfMonth)

Obtains a local date in Japanese calendar system from the era, year-of-era, month-of-year and day-of-month fields.

The Japanese month and day-of-month are the same as those in the ISO calendar system. They are not reset when the era changes. For example:

  6th Jan Showa 64 = ISO 1989-01-06
  7th Jan Showa 64 = ISO 1989-01-07
  8th Jan Heisei 1 = ISO 1989-01-08
  9th Jan Heisei 1 = ISO 1989-01-09
 

Parameters
era Era: the Japanese era, not null

yearOfEra int: the year-of-era

month int: the month-of-year

dayOfMonth int: the day-of-month

Returns
JapaneseDate the Japanese local date, not null

Throws
DateTimeException if unable to create the date
ClassCastException if the era is not a JapaneseEra

date

Added in API level 26
public JapaneseDate date (TemporalAccessor temporal)

Parameters
temporal TemporalAccessor

Returns
JapaneseDate

dateEpochDay

Added in API level 26
public JapaneseDate dateEpochDay (long epochDay)

Obtains a local date in the Japanese calendar system from the epoch-day.

Parameters
epochDay long: the epoch day

Returns
JapaneseDate the Japanese local date, not null

Throws
DateTimeException if unable to create the date

dateNow

Added in API level 26
public JapaneseDate dateNow (ZoneId zone)

Parameters
zone ZoneId

Returns
JapaneseDate

dateNow

Added in API level 26
public JapaneseDate dateNow ()

Returns
JapaneseDate

dateNow

Added in API level 26
public JapaneseDate dateNow (Clock clock)

Parameters
clock Clock

Returns
JapaneseDate

dateYearDay

Added in API level 26
public JapaneseDate dateYearDay (Era era, 
                int yearOfEra, 
                int dayOfYear)

Obtains a local date in Japanese calendar system from the era, year-of-era and day-of-year fields.

The day-of-year in this factory is expressed relative to the start of the year-of-era. This definition changes the normal meaning of day-of-year only in those years where the year-of-era is reset to one due to a change in the era. For example:

  6th Jan Showa 64 = day-of-year 6
  7th Jan Showa 64 = day-of-year 7
  8th Jan Heisei 1 = day-of-year 1
  9th Jan Heisei 1 = day-of-year 2
 

Parameters
era Era: the Japanese era, not null

yearOfEra int: the year-of-era

dayOfYear int: the day-of-year

Returns
JapaneseDate the Japanese local date, not null

Throws
DateTimeException if unable to create the date
ClassCastException if the era is not a JapaneseEra

dateYearDay

Added in API level 26
public JapaneseDate dateYearDay (int prolepticYear, 
                int dayOfYear)

Obtains a local date in Japanese calendar system from the proleptic-year and day-of-year fields.

The day-of-year in this factory is expressed relative to the start of the proleptic year. The Japanese proleptic year and day-of-year are the same as those in the ISO calendar system. They are not reset when the era changes.

Parameters
prolepticYear int: the proleptic-year

dayOfYear int: the day-of-year

Returns
JapaneseDate the Japanese local date, not null

Throws
DateTimeException if unable to create the date

eraOf

Added in API level 26
public JapaneseEra eraOf (int eraValue)

Returns the calendar system era object from the given numeric value. The numeric values supported by this method are the same as the numeric values supported by JapaneseEra#of(int).

Parameters
eraValue int: the era value

Returns
JapaneseEra the Japanese Era for the given numeric era value

Throws
DateTimeException if eraValue is invalid

eras

Added in API level 26
public List<Era> eras ()

Returns
List<Era>

getCalendarType

Added in API level 26
public String getCalendarType ()

Gets the calendar type of the underlying calendar system - 'japanese'.

The calendar type is an identifier defined by the Unicode Locale Data Markup Language (LDML) specification. It can be used to lookup the Chronology using Chronology#of(String). It can also be used as part of a locale, accessible via Locale#getUnicodeLocaleType(String) with the key 'ca'.

Returns
String the calendar system type - 'japanese'

See also:

getId

Added in API level 26
public String getId ()

Gets the ID of the chronology - 'Japanese'.

The ID uniquely identifies the Chronology. It can be used to lookup the Chronology using Chronology#of(String).

Returns
String the chronology ID - 'Japanese'

See also:

isLeapYear

Added in API level 26
public boolean isLeapYear (long prolepticYear)

Checks if the specified year is a leap year.

Japanese calendar leap years occur exactly in line with ISO leap years. This method does not validate the year passed in, and only has a well-defined result for years in the supported range.

Parameters
prolepticYear long: the proleptic-year to check, not validated for range

Returns
boolean true if the year is a leap year

localDateTime

Added in API level 26
public ChronoLocalDateTime<JapaneseDate> localDateTime (TemporalAccessor temporal)

Parameters
temporal TemporalAccessor

Returns
ChronoLocalDateTime<JapaneseDate>

prolepticYear

Added in API level 26
public int prolepticYear (Era era, 
                int yearOfEra)

Parameters
era Era

yearOfEra int

Returns
int

range

Added in API level 26
public ValueRange range (ChronoField field)

Parameters
field ChronoField

Returns
ValueRange

resolveDate

Added in API level 26
public JapaneseDate resolveDate (Map<TemporalFieldLong> fieldValues, 
                ResolverStyle resolverStyle)

Resolves parsed ChronoField values into a date during parsing.

Most TemporalField implementations are resolved using the resolve method on the field. By contrast, the ChronoField class defines fields that only have meaning relative to the chronology. As such, ChronoField date fields are resolved here in the context of a specific chronology.

ChronoField instances are resolved by this method, which may be overridden in subclasses.

  • EPOCH_DAY - If present, this is converted to a date and all other date fields are then cross-checked against the date.
  • PROLEPTIC_MONTH - If present, then it is split into the YEAR and MONTH_OF_YEAR. If the mode is strict or smart then the field is validated.
  • YEAR_OF_ERA and ERA - If both are present, then they are combined to form a YEAR. In lenient mode, the YEAR_OF_ERA range is not validated, in smart and strict mode it is. The ERA is validated for range in all three modes. If only the YEAR_OF_ERA is present, and the mode is smart or lenient, then the last available era is assumed. In strict mode, no era is assumed and the YEAR_OF_ERA is left untouched. If only the ERA is present, then it is left untouched.
  • YEAR, MONTH_OF_YEAR and DAY_OF_MONTH - If all three are present, then they are combined to form a date. In all three modes, the YEAR is validated. If the mode is smart or strict, then the month and day are validated. If the mode is lenient, then the date is combined in a manner equivalent to creating a date on the first day of the first month in the requested year, then adding the difference in months, then the difference in days. If the mode is smart, and the day-of-month is greater than the maximum for the year-month, then the day-of-month is adjusted to the last day-of-month. If the mode is strict, then the three fields must form a valid date.
  • YEAR and DAY_OF_YEAR - If both are present, then they are combined to form a date. In all three modes, the YEAR is validated. If the mode is lenient, then the date is combined in a manner equivalent to creating a date on the first day of the requested year, then adding the difference in days. If the mode is smart or strict, then the two fields must form a valid date.
  • YEAR, MONTH_OF_YEAR, ALIGNED_WEEK_OF_MONTH and ALIGNED_DAY_OF_WEEK_IN_MONTH - If all four are present, then they are combined to form a date. In all three modes, the YEAR is validated. If the mode is lenient, then the date is combined in a manner equivalent to creating a date on the first day of the first month in the requested year, then adding the difference in months, then the difference in weeks, then in days. If the mode is smart or strict, then the all four fields are validated to their outer ranges. The date is then combined in a manner equivalent to creating a date on the first day of the requested year and month, then adding the amount in weeks and days to reach their values. If the mode is strict, the date is additionally validated to check that the day and week adjustment did not change the month.
  • YEAR, MONTH_OF_YEAR, ALIGNED_WEEK_OF_MONTH and DAY_OF_WEEK - If all four are present, then they are combined to form a date. The approach is the same as described above for years, months and weeks in ALIGNED_DAY_OF_WEEK_IN_MONTH. The day-of-week is adjusted as the next or same matching day-of-week once the years, months and weeks have been handled.
  • YEAR, ALIGNED_WEEK_OF_YEAR and ALIGNED_DAY_OF_WEEK_IN_YEAR - If all three are present, then they are combined to form a date. In all three modes, the YEAR is validated. If the mode is lenient, then the date is combined in a manner equivalent to creating a date on the first day of the requested year, then adding the difference in weeks, then in days. If the mode is smart or strict, then the all three fields are validated to their outer ranges. The date is then combined in a manner equivalent to creating a date on the first day of the requested year, then adding the amount in weeks and days to reach their values. If the mode is strict, the date is additionally validated to check that the day and week adjustment did not change the year.
  • YEAR, ALIGNED_WEEK_OF_YEAR and DAY_OF_WEEK - If all three are present, then they are combined to form a date. The approach is the same as described above for years and weeks in ALIGNED_DAY_OF_WEEK_IN_YEAR. The day-of-week is adjusted as the next or same matching day-of-week once the years and weeks have been handled.

The default implementation is suitable for most calendar systems. If ChronoField.YEAR_OF_ERA is found without an ChronoField.ERA then the last era in Chronology.eras() is used. The implementation assumes a 7 day week, that the first day-of-month has the value 1, that first day-of-year has the value 1, and that the first of the month and year always exists.

Parameters
fieldValues Map: the map of fields to values, which can be updated, not null

resolverStyle ResolverStyle: the requested type of resolve, not null

Returns
JapaneseDate the resolved date, null if insufficient information to create a date

zonedDateTime

Added in API level 26
public ChronoZonedDateTime<JapaneseDate> zonedDateTime (TemporalAccessor temporal)

Parameters
temporal TemporalAccessor

Returns
ChronoZonedDateTime<JapaneseDate>

zonedDateTime

Added in API level 26
public ChronoZonedDateTime<JapaneseDate> zonedDateTime (Instant instant, 
                ZoneId zone)

Parameters
instant Instant

zone ZoneId

Returns
ChronoZonedDateTime<JapaneseDate>