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
Modifier and Type | Field | Description |
---|---|---|
static final JapaneseChronology |
INSTANCE |
Singleton instance for Japanese chronology. |
Modifier and Type | Method | Description |
---|---|---|
JapaneseDate |
date |
Obtains a local date in Japanese calendar system from the proleptic-year, month-of-year and day-of-month fields. |
JapaneseDate |
date |
Obtains a local date in Japanese calendar system from the era, year-of-era, month-of-year and day-of-month fields. |
JapaneseDate |
date |
Obtains a local date in this chronology from another temporal object. |
JapaneseDate |
dateEpochDay |
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 |
Obtains the current local date in this chronology from the specified clock. |
JapaneseDate |
dateNow |
Obtains the current local date in this chronology from the system clock in the specified time-zone. |
JapaneseDate |
dateYearDay |
Obtains a local date in Japanese calendar system from the proleptic-year and day-of-year fields. |
JapaneseDate |
dateYearDay |
Obtains a local date in Japanese calendar system from the era, year-of-era and day-of-year fields. |
JapaneseEra |
eraOf |
Returns the calendar system era object from the given numeric value. |
List |
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 |
isIsoBased() |
JapaneseChronology is an ISO based chronology, which supports fields in IsoFields , such as DAY_OF_QUARTER and QUARTER_OF_YEAR . |
boolean |
isLeapYear |
Checks if the specified year is a leap year. |
ChronoLocalDateTime |
localDateTime |
Obtains a local date-time in this chronology from another temporal object. |
int |
prolepticYear |
Calculates the proleptic-year given the era and year-of-era. |
ValueRange |
range |
Gets the range of valid values for the specified field. |
JapaneseDate |
resolveDate |
Resolves parsed ChronoField values into a date during parsing. |
ChronoZonedDateTime |
zonedDateTime |
Obtains a ChronoZonedDateTime in this chronology from an Instant . |
ChronoZonedDateTime |
zonedDateTime |
Obtains a ChronoZonedDateTime in this chronology from another temporal object. |
compareTo, equals, hashCode, toString
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
epochSecond, epochSecond, getDisplayName, period
public 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 Chronology
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 Chronology
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 Chronology
era
- 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 JapaneseEra
public 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 Chronology
prolepticYear
- 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 Chronology
era
- 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 JapaneseEra
public 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 Chronology
prolepticYear
- the proleptic-yeardayOfYear
- the day-of-yearDateTimeException
- if unable to create the datepublic JapaneseDate dateEpochDay(long epochDay)
dateEpochDay
in interface Chronology
epochDay
- 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 Chronology
public 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 Chronology
zone
- 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 Chronology
clock
- 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 Chronology
temporal
- the temporal object to convert, not nullpublic 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 Chronology
temporal
- the temporal object to convert, not nullpublic ChronoZonedDateTime<JapaneseDate> zonedDateTime(TemporalAccessor temporal)
Chronology
ChronoZonedDateTime
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 Chronology
temporal
- the temporal object to convert, not nullpublic ChronoZonedDateTime<JapaneseDate> zonedDateTime(Instant instant, ZoneId zone)
Chronology
ChronoZonedDateTime
in this chronology from an Instant
. This obtains a zoned date-time with the same instant as that specified.
zonedDateTime
in interface Chronology
instant
- 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 Chronology
prolepticYear
- the proleptic-year to check, not validated for rangepublic int prolepticYear(Era era, int yearOfEra)
Chronology
This 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 Chronology
era
- the era of the correct type for the chronology, not nullyearOfEra
- the chronology year-of-erapublic JapaneseEra eraOf(int eraValue)
JapaneseEra.of(int)
.eraOf
in interface Chronology
eraValue
- the era valueEra
for the given numeric era valueDateTimeException
- if eraValue
is invalidpublic List<Era> eras()
Chronology
Most 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 Chronology
public 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 Chronology
field
- the field to get the range for, not nullpublic JapaneseDate resolveDate(Map<TemporalField,Long> fieldValues, ResolverStyle resolverStyle)
AbstractChronology
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.
resolveDate
in interface Chronology
resolveDate
in class AbstractChronology
fieldValues
- the map of fields to values, which can be updated, not nullresolverStyle
- the requested type of resolve, not nullpublic boolean isIsoBased()
JapaneseChronology
is an ISO based chronology, which supports fields in IsoFields
, such as DAY_OF_QUARTER
and QUARTER_OF_YEAR
.isIsoBased
in interface Chronology
true
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