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
| Modifier and Type | Field and Description |
|---|---|
static JapaneseChronology |
INSTANCE
Singleton instance for Japanese chronology.
|
| Modifier and Type | Method and Description |
|---|---|
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(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(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(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()
Gets the list of eras for the chronology.
|
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.
|
int |
prolepticYear(Era era,
int yearOfEra)
Calculates the proleptic-year given the era and year-of-era.
|
ValueRange |
range(ChronoField field)
Gets the range of valid values for the specified field.
|
JapaneseDate |
resolveDate(Map<TemporalField,Long> fieldValues,
ResolverStyle resolverStyle)
Resolves parsed
ChronoField values into a date during parsing. |
ChronoZonedDateTime<JapaneseDate> |
zonedDateTime(Instant instant,
ZoneId zone)
Obtains a
ChronoZonedDateTime in this chronology from an Instant. |
ChronoZonedDateTime<JapaneseDate> |
zonedDateTime(TemporalAccessor temporal)
Obtains a
ChronoZonedDateTime in this chronology from another temporal object. |
compareTo, equals, hashCode, toStringclone, finalize, getClass, notify, notifyAll, wait, wait, waitfrom, getDisplayName, periodpublic static final JapaneseChronology INSTANCE
public String getId()
The ID uniquely identifies the Chronology.
It can be used to lookup the Chronology using Chronology.of(String).
getId in interface ChronologygetCalendarType()public String getCalendarType()
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'.
getCalendarType in interface ChronologygetId()public JapaneseDate date(Era era, int yearOfEra, int month, int dayOfMonth)
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
date in interface Chronologyera - the Japanese era, not nullyearOfEra - the year-of-eramonth - the month-of-yeardayOfMonth - the day-of-monthDateTimeException - if unable to create the dateClassCastException - if the era is not a JapaneseErapublic JapaneseDate date(int prolepticYear, int month, int dayOfMonth)
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.
date in interface ChronologyprolepticYear - the proleptic-yearmonth - the month-of-yeardayOfMonth - the day-of-monthDateTimeException - if unable to create the datepublic JapaneseDate dateYearDay(Era era, int yearOfEra, int dayOfYear)
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
dateYearDay in interface Chronologyera - the Japanese era, not nullyearOfEra - the year-of-eradayOfYear - the day-of-yearDateTimeException - if unable to create the dateClassCastException - if the era is not a JapaneseErapublic JapaneseDate dateYearDay(int prolepticYear, int dayOfYear)
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.
dateYearDay in interface ChronologyprolepticYear - the proleptic-yeardayOfYear - the day-of-yearDateTimeException - if unable to create the datepublic JapaneseDate dateEpochDay(long epochDay)
dateEpochDay in interface ChronologyepochDay - the epoch dayDateTimeException - if unable to create the datepublic JapaneseDate dateNow()
Chronology
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.
dateNow in interface Chronologypublic JapaneseDate dateNow(ZoneId zone)
Chronology
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.
dateNow in interface Chronologyzone - the zone ID to use, not nullpublic JapaneseDate dateNow(Clock clock)
Chronology
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.
dateNow in interface Chronologyclock - the clock to use, not nullpublic JapaneseDate date(TemporalAccessor temporal)
Chronology
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 of ChronoLocalDate.
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.
date in interface Chronologytemporal - the temporal object to convert, not nullChronoLocalDate.from(TemporalAccessor)public ChronoLocalDateTime<JapaneseDate> localDateTime(TemporalAccessor temporal)
Chronology
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 of ChronoLocalDateTime.
The conversion extracts and combines the ChronoLocalDate and the
LocalTime 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.
localDateTime in interface Chronologytemporal - the temporal object to convert, not nullChronoLocalDateTime.from(TemporalAccessor)public ChronoZonedDateTime<JapaneseDate> zonedDateTime(TemporalAccessor temporal)
ChronologyChronoZonedDateTime 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 of ChronoZonedDateTime.
The conversion will first obtain a ZoneId from the temporal object,
falling back to a ZoneOffset if necessary. It will then try to obtain
an Instant, falling back to a ChronoLocalDateTime if necessary.
The result will be either the combination of ZoneId or ZoneOffset
with Instant or ChronoLocalDateTime.
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.
zonedDateTime in interface Chronologytemporal - the temporal object to convert, not nullChronoZonedDateTime.from(TemporalAccessor)public ChronoZonedDateTime<JapaneseDate> zonedDateTime(Instant instant, ZoneId zone)
ChronologyChronoZonedDateTime in this chronology from an Instant.
This obtains a zoned date-time with the same instant as that specified.
zonedDateTime in interface Chronologyinstant - the instant to create the date-time from, not nullzone - the time-zone, not nullpublic boolean isLeapYear(long prolepticYear)
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.
isLeapYear in interface ChronologyprolepticYear - the proleptic-year to check, not validated for rangepublic int prolepticYear(Era era, int yearOfEra)
ChronologyThis combines the era and year-of-era into the single proleptic-year field.
If the chronology makes active use of eras, such as JapaneseChronology
then the year-of-era will be validated against the era.
For other chronologies, validation is optional.
prolepticYear in interface Chronologyera - the era of the correct type for the chronology, not nullyearOfEra - the chronology year-of-erapublic JapaneseEra eraOf(int eraValue)
JapaneseEra.HEISEI, JapaneseEra.SHOWA,JapaneseEra.TAISHO,
JapaneseEra.MEIJI), only Meiji and later eras are supported.eraOf in interface ChronologyeraValue - the era valueEra for the given numeric era valueDateTimeException - if eraValue is invalidpublic List<Era> eras()
ChronologyMost calendar systems have an era, within which the year has meaning. If the calendar system does not support the concept of eras, an empty list must be returned.
eras in interface Chronologypublic ValueRange range(ChronoField field)
Chronology
All fields can be expressed as a long integer.
This method returns an object that describes the valid range for that value.
Note that the result only describes the minimum and maximum valid values and it is important not to read too much into them. For example, there could be values within the range that are invalid for the field.
This method will return a result whether or not the chronology supports the field.
range in interface Chronologyfield - the field to get the range for, not nullpublic JapaneseDate resolveDate(Map<TemporalField,Long> fieldValues, ResolverStyle resolverStyle)
AbstractChronologyChronoField 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.
resolveDate in interface ChronologyresolveDate in class AbstractChronologyfieldValues - the map of fields to values, which can be updated, not nullresolverStyle - the requested type of resolve, not null Submit a bug or feature
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