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/*
* Copyright (c) 2007-present, Stephen Colebourne & Michael Nascimento Santos
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of JSR-310 nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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package org.threeten.extra.chrono;
import java.io.Serializable;
import java.time.Clock;
import java.time.DateTimeException;
import java.time.Instant;
import java.time.ZoneId;
import java.time.chrono.AbstractChronology;
import java.time.chrono.ChronoLocalDateTime;
import java.time.chrono.ChronoZonedDateTime;
import java.time.chrono.Chronology;
import java.time.chrono.Era;
import java.time.format.ResolverStyle;
import java.time.temporal.ChronoField;
import java.time.temporal.TemporalAccessor;
import java.time.temporal.TemporalField;
import java.time.temporal.ValueRange;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
/**
* 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 {@code 0001-01-01 (Julian)} is {@code 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.
*/
public final class JulianChronology extends AbstractChronology implements Serializable {
/**
* Singleton instance for the Julian chronology.
*/
public static final JulianChronology INSTANCE = new JulianChronology();
/**
* Serialization version.
*/
private static final long serialVersionUID = 7291205177830286973L;
/**
* Range of proleptic-year.
*/
static final ValueRange YEAR_RANGE = ValueRange.of(-999_998, 999_999);
/**
* Range of year.
*/
static final ValueRange YOE_RANGE = ValueRange.of(1, 999_999);
/**
* Range of proleptic month.
*/
static final ValueRange PROLEPTIC_MONTH_RANGE = ValueRange.of(-999_998 * 12L, 999_999 * 12L + 11);
/**
* Private constructor, that is public to satisfy the {@code ServiceLoader}.
* @deprecated Use the singleton {@link #INSTANCE} instead.
*/
@Deprecated
public JulianChronology() {
}
/**
* Resolve singleton.
*
* @return the singleton instance, not null
*/
private Object readResolve() {
return INSTANCE;
}
//-----------------------------------------------------------------------
/**
* Gets the ID of the chronology - 'Julian'.
*
* The ID uniquely identifies the {@code Chronology}.
* It can be used to lookup the {@code Chronology} using {@link Chronology#of(String)}.
*
* @return the chronology ID - 'Julian'
* @see #getCalendarType()
*/
@Override
public String getId() {
return "Julian";
}
/**
* 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.
*
* @return the calendar system type - 'julian'
* @see #getId()
*/
@Override
public String getCalendarType() {
return "julian";
}
//-----------------------------------------------------------------------
/**
* Obtains a local date in Julian calendar system from the
* era, year-of-era, month-of-year and day-of-month fields.
*
* @param era the Julian era, not null
* @param yearOfEra the year-of-era
* @param month the month-of-year
* @param dayOfMonth the day-of-month
* @return the Julian local date, not null
* @throws DateTimeException if unable to create the date
* @throws ClassCastException if the {@code era} is not a {@code JulianEra}
*/
@Override
public JulianDate date(Era era, int yearOfEra, int month, int dayOfMonth) {
return date(prolepticYear(era, yearOfEra), month, dayOfMonth);
}
/**
* Obtains a local date in Julian calendar system from the
* proleptic-year, month-of-year and day-of-month fields.
*
* @param prolepticYear the proleptic-year
* @param month the month-of-year
* @param dayOfMonth the day-of-month
* @return the Julian local date, not null
* @throws DateTimeException if unable to create the date
*/
@Override
public JulianDate date(int prolepticYear, int month, int dayOfMonth) {
return JulianDate.of(prolepticYear, month, dayOfMonth);
}
/**
* Obtains a local date in Julian calendar system from the
* era, year-of-era and day-of-year fields.
*
* @param era the Julian era, not null
* @param yearOfEra the year-of-era
* @param dayOfYear the day-of-year
* @return the Julian local date, not null
* @throws DateTimeException if unable to create the date
* @throws ClassCastException if the {@code era} is not a {@code JulianEra}
*/
@Override
public JulianDate dateYearDay(Era era, int yearOfEra, int dayOfYear) {
return dateYearDay(prolepticYear(era, yearOfEra), dayOfYear);
}
/**
* Obtains a local date in Julian calendar system from the
* proleptic-year and day-of-year fields.
*
* @param prolepticYear the proleptic-year
* @param dayOfYear the day-of-year
* @return the Julian local date, not null
* @throws DateTimeException if unable to create the date
*/
@Override
public JulianDate dateYearDay(int prolepticYear, int dayOfYear) {
return JulianDate.ofYearDay(prolepticYear, dayOfYear);
}
/**
* Obtains a local date in the Julian calendar system from the epoch-day.
*
* @param epochDay the epoch day
* @return the Julian local date, not null
* @throws DateTimeException if unable to create the date
*/
@Override // override with covariant return type
public JulianDate dateEpochDay(long epochDay) {
return JulianDate.ofEpochDay(epochDay);
}
//-------------------------------------------------------------------------
/**
* Obtains the current Julian local date from the system clock in the default time-zone.
*
* This will query the {@link Clock#systemDefaultZone() 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.
*
* @return the current Julian local date using the system clock and default time-zone, not null
* @throws DateTimeException if unable to create the date
*/
@Override // override with covariant return type
public JulianDate dateNow() {
return JulianDate.now();
}
/**
* Obtains the current Julian local date from the system clock in the specified time-zone.
*
* This will query the {@link Clock#system(ZoneId) 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.
*
* @param zone the zone ID to use, not null
* @return the current Julian local date using the system clock, not null
* @throws DateTimeException if unable to create the date
*/
@Override // override with covariant return type
public JulianDate dateNow(ZoneId zone) {
return JulianDate.now(zone);
}
/**
* 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 {@link Clock dependency injection}.
*
* @param clock the clock to use, not null
* @return the current Julian local date, not null
* @throws DateTimeException if unable to create the date
*/
@Override // override with covariant return type
public JulianDate dateNow(Clock clock) {
return JulianDate.now(clock);
}
//-------------------------------------------------------------------------
/**
* Obtains a Julian local date from another date-time object.
*
* @param temporal the date-time object to convert, not null
* @return the Julian local date, not null
* @throws DateTimeException if unable to create the date
*/
@Override
public JulianDate date(TemporalAccessor temporal) {
return JulianDate.from(temporal);
}
/**
* Obtains a Julian local date-time from another date-time object.
*
* @param temporal the date-time object to convert, not null
* @return the Julian local date-time, not null
* @throws DateTimeException if unable to create the date-time
*/
@Override
@SuppressWarnings("unchecked")
public ChronoLocalDateTime localDateTime(TemporalAccessor temporal) {
return (ChronoLocalDateTime) super.localDateTime(temporal);
}
/**
* Obtains a Julian zoned date-time from another date-time object.
*
* @param temporal the date-time object to convert, not null
* @return the Julian zoned date-time, not null
* @throws DateTimeException if unable to create the date-time
*/
@Override
@SuppressWarnings("unchecked")
public ChronoZonedDateTime zonedDateTime(TemporalAccessor temporal) {
return (ChronoZonedDateTime) super.zonedDateTime(temporal);
}
/**
* Obtains a Julian zoned date-time in this chronology from an {@code Instant}.
*
* @param instant the instant to create the date-time from, not null
* @param zone the time-zone, not null
* @return the Julian zoned date-time, not null
* @throws DateTimeException if the result exceeds the supported range
*/
@Override
@SuppressWarnings("unchecked")
public ChronoZonedDateTime zonedDateTime(Instant instant, ZoneId zone) {
return (ChronoZonedDateTime) super.zonedDateTime(instant, zone);
}
//-----------------------------------------------------------------------
/**
* 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.
*
* @param prolepticYear the proleptic-year to check, not validated for range
* @return true if the year is a leap year
*/
@Override
public boolean isLeapYear(long prolepticYear) {
return (prolepticYear % 4) == 0;
}
@Override
public int prolepticYear(Era era, int yearOfEra) {
if (era instanceof JulianEra == false) {
throw new ClassCastException("Era must be JulianEra");
}
return (era == JulianEra.AD ? yearOfEra : 1 - yearOfEra);
}
@Override
public JulianEra eraOf(int eraValue) {
return JulianEra.of(eraValue);
}
@Override
public List eras() {
return Arrays.asList(JulianEra.values());
}
//-----------------------------------------------------------------------
@Override
public ValueRange range(ChronoField field) {
switch (field) {
case PROLEPTIC_MONTH:
return PROLEPTIC_MONTH_RANGE;
case YEAR_OF_ERA:
return YOE_RANGE;
case YEAR:
return YEAR_RANGE;
default:
break;
}
return field.range();
}
//-----------------------------------------------------------------------
@Override // override for return type
public JulianDate resolveDate(Map fieldValues, ResolverStyle resolverStyle) {
return (JulianDate) super.resolveDate(fieldValues, resolverStyle);
}
}