- All Implemented Interfaces:
Serializable
,Comparable<Chronology>
,Chronology
public final class JapaneseChronology extends AbstractChronology implements Serializable
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
- Implementation Requirements:
- This class is immutable and thread-safe.
- Since:
- 1.8
- See Also:
- Serialized Form
-
Field Summary
Fields Modifier and Type Field Description static JapaneseChronology
INSTANCE
Singleton instance for Japanese chronology. -
Method Summary
Modifier and Type Method Description 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)
Obtains a local date in this chronology from another temporal object.JapaneseDate
dateEpochDay(long epochDay)
Obtains a local date in the Japanese calendar system from the epoch-day.JapaneseDate
dateNow()
Obtains the current local date in this chronology from the system clock in the default time-zone.JapaneseDate
dateNow(Clock clock)
Obtains the current local date in this chronology from the specified clock.JapaneseDate
dateNow(ZoneId zone)
Obtains the current local date in this chronology from the system clock in the specified time-zone.JapaneseDate
dateYearDay(int prolepticYear, int dayOfYear)
Obtains a local date in Japanese calendar system from the proleptic-year and day-of-year fields.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.JapaneseEra
eraOf(int eraValue)
Returns the calendar system era object from the given numeric value.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)
Obtains a local date-time in this chronology from another temporal object.JapaneseDate
resolveDate(Map<TemporalField,Long> fieldValues, ResolverStyle resolverStyle)
Resolves parsedChronoField
values into a date during parsing.ChronoZonedDateTime<JapaneseDate>
zonedDateTime(Instant instant, ZoneId zone)
Obtains aChronoZonedDateTime
in this chronology from anInstant
.ChronoZonedDateTime<JapaneseDate>
zonedDateTime(TemporalAccessor temporal)
Obtains aChronoZonedDateTime
in this chronology from another temporal object.Methods declared in class java.time.chrono.AbstractChronology
compareTo, equals, hashCode, toString
Methods declared in class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
Methods declared in interface java.time.chrono.Chronology
epochSecond, epochSecond, eras, getDisplayName, period, prolepticYear, range
-
Field Details
-
INSTANCE
Singleton instance for Japanese chronology.
-
-
Method Details
-
getId
Gets the ID of the chronology - 'Japanese'.The ID uniquely identifies the
Chronology
. It can be used to lookup theChronology
usingChronology.of(String)
.- Specified by:
getId
in interfaceChronology
- Returns:
- the chronology ID - 'Japanese'
- See Also:
getCalendarType()
-
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
usingChronology.of(String)
. It can also be used as part of a locale, accessible viaLocale.getUnicodeLocaleType(String)
with the key 'ca'.- Specified by:
getCalendarType
in interfaceChronology
- Returns:
- the calendar system type - 'japanese'
- See Also:
getId()
-
date
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
- Specified by:
date
in interfaceChronology
- Parameters:
era
- the Japanese era, not nullyearOfEra
- the year-of-eramonth
- the month-of-yeardayOfMonth
- the day-of-month- Returns:
- the Japanese local date, not null
- Throws:
DateTimeException
- if unable to create the dateClassCastException
- if theera
is not aJapaneseEra
-
date
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.
- Specified by:
date
in interfaceChronology
- Parameters:
prolepticYear
- the proleptic-yearmonth
- the month-of-yeardayOfMonth
- the day-of-month- Returns:
- the Japanese local date, not null
- Throws:
DateTimeException
- if unable to create the date
-
dateYearDay
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
- Specified by:
dateYearDay
in interfaceChronology
- Parameters:
era
- the Japanese era, not nullyearOfEra
- the year-of-eradayOfYear
- the day-of-year- Returns:
- the Japanese local date, not null
- Throws:
DateTimeException
- if unable to create the dateClassCastException
- if theera
is not aJapaneseEra
-
dateYearDay
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.
- Specified by:
dateYearDay
in interfaceChronology
- Parameters:
prolepticYear
- the proleptic-yeardayOfYear
- the day-of-year- Returns:
- the Japanese local date, not null
- Throws:
DateTimeException
- if unable to create the date
-
dateEpochDay
Obtains a local date in the Japanese calendar system from the epoch-day.- Specified by:
dateEpochDay
in interfaceChronology
- Parameters:
epochDay
- the epoch day- Returns:
- the Japanese local date, not null
- Throws:
DateTimeException
- if unable to create the date
-
dateNow
Description copied from interface:Chronology
Obtains the current local date in this chronology from the system clock in the default time-zone.This will query the
system clock
in the default time-zone to obtain the current date.Using this method will prevent the ability to use an alternate clock for testing because the clock is hard-coded.
- Specified by:
dateNow
in interfaceChronology
- Returns:
- the current local date using the system clock and default time-zone, not null
-
dateNow
Description copied from interface:Chronology
Obtains the current local date in this chronology from the system clock in the specified time-zone.This will query the
system clock
to obtain the current date. Specifying the time-zone avoids dependence on the default time-zone.Using this method will prevent the ability to use an alternate clock for testing because the clock is hard-coded.
- Specified by:
dateNow
in interfaceChronology
- Parameters:
zone
- the zone ID to use, not null- Returns:
- the current local date using the system clock, not null
-
dateNow
Description copied from interface:Chronology
Obtains the current local date in this chronology from the specified clock.This will query the specified clock to obtain the current date - today. Using this method allows the use of an alternate clock for testing. The alternate clock may be introduced using
dependency injection
.- Specified by:
dateNow
in interfaceChronology
- Parameters:
clock
- the clock to use, not null- Returns:
- the current local date, not null
-
date
Description copied from interface:Chronology
Obtains a local date in this chronology from another temporal object.This obtains a date in this chronology based on the specified temporal. A
TemporalAccessor
represents an arbitrary set of date and time information, which this factory converts to an instance ofChronoLocalDate
.The conversion typically uses the
EPOCH_DAY
field, which is standardized across calendar systems.This method matches the signature of the functional interface
TemporalQuery
allowing it to be used as a query via method reference,aChronology::date
.- Specified by:
date
in interfaceChronology
- Parameters:
temporal
- the temporal object to convert, not null- Returns:
- the local date in this chronology, not null
- See Also:
ChronoLocalDate.from(TemporalAccessor)
-
localDateTime
Description copied from interface:Chronology
Obtains a local date-time in this chronology from another temporal object.This obtains a date-time in this chronology based on the specified temporal. A
TemporalAccessor
represents an arbitrary set of date and time information, which this factory converts to an instance ofChronoLocalDateTime
.The conversion extracts and combines the
ChronoLocalDate
and theLocalTime
from the temporal object. Implementations are permitted to perform optimizations such as accessing those fields that are equivalent to the relevant objects. The result uses this chronology.This method matches the signature of the functional interface
TemporalQuery
allowing it to be used as a query via method reference,aChronology::localDateTime
.- Specified by:
localDateTime
in interfaceChronology
- Parameters:
temporal
- the temporal object to convert, not null- Returns:
- the local date-time in this chronology, not null
- See Also:
ChronoLocalDateTime.from(TemporalAccessor)
-
zonedDateTime
Description copied from interface:Chronology
Obtains aChronoZonedDateTime
in this chronology from another temporal object.This obtains a zoned date-time in this chronology based on the specified temporal. A
TemporalAccessor
represents an arbitrary set of date and time information, which this factory converts to an instance ofChronoZonedDateTime
.The conversion will first obtain a
ZoneId
from the temporal object, falling back to aZoneOffset
if necessary. It will then try to obtain anInstant
, falling back to aChronoLocalDateTime
if necessary. The result will be either the combination ofZoneId
orZoneOffset
withInstant
orChronoLocalDateTime
. Implementations are permitted to perform optimizations such as accessing those fields that are equivalent to the relevant objects. The result uses this chronology.This method matches the signature of the functional interface
TemporalQuery
allowing it to be used as a query via method reference,aChronology::zonedDateTime
.- Specified by:
zonedDateTime
in interfaceChronology
- Parameters:
temporal
- the temporal object to convert, not null- Returns:
- the zoned date-time in this chronology, not null
- See Also:
ChronoZonedDateTime.from(TemporalAccessor)
-
zonedDateTime
Description copied from interface:Chronology
Obtains aChronoZonedDateTime
in this chronology from anInstant
.This obtains a zoned date-time with the same instant as that specified.
- Specified by:
zonedDateTime
in interfaceChronology
- Parameters:
instant
- the instant to create the date-time from, not nullzone
- the time-zone, not null- Returns:
- the zoned date-time, not null
-
isLeapYear
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.
- Specified by:
isLeapYear
in interfaceChronology
- Parameters:
prolepticYear
- the proleptic-year to check, not validated for range- Returns:
- true if the year is a leap year
-
eraOf
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 byJapaneseEra.of(int)
.- Specified by:
eraOf
in interfaceChronology
- Parameters:
eraValue
- the era value- Returns:
- the Japanese
Era
for the given numeric era value - Throws:
DateTimeException
- iferaValue
is invalid
-
resolveDate
Description copied from class:AbstractChronology
Resolves parsedChronoField
values into a date during parsing.Most
TemporalField
implementations are resolved using the resolve method on the field. By contrast, theChronoField
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 theYEAR
andMONTH_OF_YEAR
. If the mode is strict or smart then the field is validated.YEAR_OF_ERA
andERA
- If both are present, then they are combined to form aYEAR
. In lenient mode, theYEAR_OF_ERA
range is not validated, in smart and strict mode it is. TheERA
is validated for range in all three modes. If only theYEAR_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 theYEAR_OF_ERA
is left untouched. If only theERA
is present, then it is left untouched.YEAR
,MONTH_OF_YEAR
andDAY_OF_MONTH
- If all three are present, then they are combined to form a date. In all three modes, theYEAR
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
andDAY_OF_YEAR
- If both are present, then they are combined to form a date. In all three modes, theYEAR
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
andALIGNED_DAY_OF_WEEK_IN_MONTH
- If all four are present, then they are combined to form a date. In all three modes, theYEAR
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
andDAY_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 inALIGNED_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
andALIGNED_DAY_OF_WEEK_IN_YEAR
- If all three are present, then they are combined to form a date. In all three modes, theYEAR
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
andDAY_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 inALIGNED_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 anChronoField.ERA
then the last era inChronology.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.- Specified by:
resolveDate
in interfaceChronology
- Overrides:
resolveDate
in classAbstractChronology
- Parameters:
fieldValues
- the map of fields to values, which can be updated, not nullresolverStyle
- the requested type of resolve, not null- Returns:
- the resolved date, null if insufficient information to create a date
-