org.threeten.extra.chrono

Class JulianChronology

java.lang.Object

java.time.chrono.AbstractChronology

org.threeten.extra.chrono.JulianChronology

All Implemented Interfaces:

Serializable, Comparable<java.time.chrono.Chronology>, java.time.chrono.Chronology

public final class JulianChronology
extends java.time.chrono.AbstractChronology
implements Serializable

The Julian calendar system.

This chronology defines the rules of the proleptic Julian calendar system. This calendar system is the forerunner to the modern Gregorian and ISO calendars. The Julian differs from the Gregorian only in terms of the leap year rule. Dates are aligned such that 0001-01-01 (Julian) is 0000-12-30 (ISO).

This class is proleptic. It implements Julian rules to the entire time-line.

This class implements a calendar where January 1st is the start of the year. The history of the start of the year is complex and using the current standard is the most consistent.

The fields are defined as follows:

• era - There are two eras, the current 'Anno Domini' (AD) and the previous era 'Before Christ' (BC).
• year-of-era - The year-of-era for the current era increases uniformly from the epoch at year one. For the previous era the year increases from one as time goes backwards.
• proleptic-year - The proleptic year is the same as the year-of-era for the current era. For the previous era, years have zero, then negative values.
• month-of-year - There are 12 months in a Julian year, numbered from 1 to 12.
• day-of-month - There are between 28 and 31 days in each Julian month, numbered from 1 to 31. Months 4, 6, 9 and 11 have 30 days, Months 1, 3, 5, 7, 8, 10 and 12 have 31 days. Month 2 has 28 days, or 29 in a leap year.
• day-of-year - There are 365 days in a standard Julian year and 366 in a leap year. The days are numbered from 1 to 365 or 1 to 366.
• leap-year - Leap years occur every 4 years.

Implementation Requirements

This class is immutable and thread-safe.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static JulianChronology	INSTANCE Singleton instance for the Julian chronology.

Constructor Summary

Constructors

Constructor and Description
JulianChronology() Deprecated. Use the singleton INSTANCE instead.

Method Summary

Modifier and Type	Method and Description
JulianDate	date(java.time.chrono.Era era, int yearOfEra, int month, int dayOfMonth) Obtains a local date in Julian calendar system from the era, year-of-era, month-of-year and day-of-month fields.
JulianDate	date(int prolepticYear, int month, int dayOfMonth) Obtains a local date in Julian calendar system from the proleptic-year, month-of-year and day-of-month fields.
JulianDate	date(java.time.temporal.TemporalAccessor temporal) Obtains a Julian local date from another date-time object.
JulianDate	dateEpochDay(long epochDay) Obtains a local date in the Julian calendar system from the epoch-day.
JulianDate	dateNow() Obtains the current Julian local date from the system clock in the default time-zone.
JulianDate	dateNow(java.time.Clock clock) Obtains the current Julian local date from the specified clock.
JulianDate	dateNow(java.time.ZoneId zone) Obtains the current Julian local date from the system clock in the specified time-zone.
JulianDate	dateYearDay(java.time.chrono.Era era, int yearOfEra, int dayOfYear) Obtains a local date in Julian calendar system from the era, year-of-era and day-of-year fields.
JulianDate	dateYearDay(int prolepticYear, int dayOfYear) Obtains a local date in Julian calendar system from the proleptic-year and day-of-year fields.
JulianEra	eraOf(int eraValue)
List<java.time.chrono.Era>	eras()
String	getCalendarType() Gets the calendar type of the underlying calendar system - 'julian'.
String	getId() Gets the ID of the chronology - 'Julian'.
boolean	isLeapYear(long prolepticYear) Checks if the specified year is a leap year.
java.time.chrono.ChronoLocalDateTime<JulianDate>	localDateTime(java.time.temporal.TemporalAccessor temporal) Obtains a Julian local date-time from another date-time object.
int	prolepticYear(java.time.chrono.Era era, int yearOfEra)
java.time.temporal.ValueRange	range(java.time.temporal.ChronoField field)
JulianDate	resolveDate(Map<java.time.temporal.TemporalField,Long> fieldValues, java.time.format.ResolverStyle resolverStyle)
java.time.chrono.ChronoZonedDateTime<JulianDate>	zonedDateTime(java.time.Instant instant, java.time.ZoneId zone) Obtains a Julian zoned date-time in this chronology from an Instant.
java.time.chrono.ChronoZonedDateTime<JulianDate>	zonedDateTime(java.time.temporal.TemporalAccessor temporal) Obtains a Julian zoned date-time from another date-time object.

Methods inherited from class java.time.chrono.AbstractChronology

compareTo, equals, hashCode, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.time.chrono.Chronology

from, getDisplayName, period

Field Detail

INSTANCE

public static final JulianChronology INSTANCE

Singleton instance for the Julian chronology.

Constructor Detail

JulianChronology

@Deprecated
public JulianChronology()

Deprecated. Use the singleton INSTANCE instead.

Private constructor, that is public to satisfy the ServiceLoader.

Method Detail

getId

public String getId()

Gets the ID of the chronology - 'Julian'.

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

Specified by:

getId in interface java.time.chrono.Chronology

Returns:

the chronology ID - 'Julian'

See Also:

getCalendarType()

getCalendarType

public String getCalendarType()

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

The Unicode Locale Data Markup Language (LDML) specification does not define an identifier for the Julian calendar, but were it to do so, 'julian' is highly likely to be chosen.

Specified by:

getCalendarType in interface java.time.chrono.Chronology

Returns:

the calendar system type - 'julian'

See Also:

getId()

date

public JulianDate date(java.time.chrono.Era era,
                       int yearOfEra,
                       int month,
                       int dayOfMonth)

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

Specified by:

date in interface java.time.chrono.Chronology

Parameters:

era - the Julian era, not null

yearOfEra - the year-of-era

month - the month-of-year

dayOfMonth - the day-of-month

Returns:

the Julian local date, not null

Throws:

java.time.DateTimeException - if unable to create the date

ClassCastException - if the era is not a JulianEra

date

public JulianDate date(int prolepticYear,
                       int month,
                       int dayOfMonth)

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

Specified by:

date in interface java.time.chrono.Chronology

Parameters:

prolepticYear - the proleptic-year

month - the month-of-year

dayOfMonth - the day-of-month

Returns:

the Julian local date, not null

Throws:

java.time.DateTimeException - if unable to create the date

dateYearDay

public JulianDate dateYearDay(java.time.chrono.Era era,
                              int yearOfEra,
                              int dayOfYear)

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

Specified by:

dateYearDay in interface java.time.chrono.Chronology

Parameters:

era - the Julian era, not null

yearOfEra - the year-of-era

dayOfYear - the day-of-year

Returns:

the Julian local date, not null

Throws:

java.time.DateTimeException - if unable to create the date

ClassCastException - if the era is not a JulianEra

dateYearDay

public JulianDate dateYearDay(int prolepticYear,
                              int dayOfYear)

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

Specified by:

dateYearDay in interface java.time.chrono.Chronology

Parameters:

prolepticYear - the proleptic-year

dayOfYear - the day-of-year

Returns:

the Julian local date, not null

Throws:

java.time.DateTimeException - if unable to create the date

dateEpochDay

public JulianDate dateEpochDay(long epochDay)

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

Specified by:

dateEpochDay in interface java.time.chrono.Chronology

Parameters:

epochDay - the epoch day

Returns:

the Julian local date, not null

Throws:

java.time.DateTimeException - if unable to create the date

dateNow

public JulianDate dateNow()

Obtains the current Julian local date 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 interface java.time.chrono.Chronology

Returns:

the current Julian local date using the system clock and default time-zone, not null

Throws:

java.time.DateTimeException - if unable to create the date

dateNow

public JulianDate dateNow(java.time.ZoneId zone)

Obtains the current Julian local date 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 interface java.time.chrono.Chronology

Parameters:

zone - the zone ID to use, not null

Returns:

the current Julian local date using the system clock, not null

Throws:

java.time.DateTimeException - if unable to create the date

dateNow

public JulianDate dateNow(java.time.Clock clock)

Obtains the current Julian local date 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 interface java.time.chrono.Chronology

Parameters:

clock - the clock to use, not null

Returns:

the current Julian local date, not null

Throws:

java.time.DateTimeException - if unable to create the date

date

public JulianDate date(java.time.temporal.TemporalAccessor temporal)

Obtains a Julian local date from another date-time object.

Specified by:

date in interface java.time.chrono.Chronology

Parameters:

temporal - the date-time object to convert, not null

Returns:

the Julian local date, not null

Throws:

java.time.DateTimeException - if unable to create the date

localDateTime

public java.time.chrono.ChronoLocalDateTime<JulianDate> localDateTime(java.time.temporal.TemporalAccessor temporal)

Obtains a Julian local date-time from another date-time object.

Specified by:

localDateTime in interface java.time.chrono.Chronology

Parameters:

temporal - the date-time object to convert, not null

Returns:

the Julian local date-time, not null

Throws:

java.time.DateTimeException - if unable to create the date-time

zonedDateTime

public java.time.chrono.ChronoZonedDateTime<JulianDate> zonedDateTime(java.time.temporal.TemporalAccessor temporal)

Obtains a Julian zoned date-time from another date-time object.

Specified by:

zonedDateTime in interface java.time.chrono.Chronology

Parameters:

temporal - the date-time object to convert, not null

Returns:

the Julian zoned date-time, not null

Throws:

java.time.DateTimeException - if unable to create the date-time

zonedDateTime

public java.time.chrono.ChronoZonedDateTime<JulianDate> zonedDateTime(java.time.Instant instant,
                                                                      java.time.ZoneId zone)

Obtains a Julian zoned date-time in this chronology from an Instant.

Specified by:

zonedDateTime in interface java.time.chrono.Chronology

Parameters:

instant - the instant to create the date-time from, not null

zone - the time-zone, not null

Returns:

the Julian zoned date-time, not null

Throws:

java.time.DateTimeException - if the result exceeds the supported range

isLeapYear

public boolean isLeapYear(long prolepticYear)

Checks if the specified year is a leap year.

A Julian proleptic-year is leap if the remainder after division by four equals zero. 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 interface java.time.chrono.Chronology

Parameters:

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

Returns:

true if the year is a leap year

prolepticYear

public int prolepticYear(java.time.chrono.Era era,
                         int yearOfEra)

Specified by:

prolepticYear in interface java.time.chrono.Chronology

eraOf

public JulianEra eraOf(int eraValue)

Specified by:

eraOf in interface java.time.chrono.Chronology

eras

public List<java.time.chrono.Era> eras()

Specified by:

eras in interface java.time.chrono.Chronology

range

public java.time.temporal.ValueRange range(java.time.temporal.ChronoField field)

Specified by:

range in interface java.time.chrono.Chronology

resolveDate

public JulianDate resolveDate(Map<java.time.temporal.TemporalField,Long> fieldValues,
                              java.time.format.ResolverStyle resolverStyle)

Specified by:

resolveDate in interface java.time.chrono.Chronology

Overrides:

resolveDate in class java.time.chrono.AbstractChronology