PersianCalendar.java
// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
* Copyright (C) 1996-2014, International Business Machines Corporation and *
* others. All Rights Reserved. *
*******************************************************************************
*/
package com.ibm.icu.util;
import com.ibm.icu.util.ULocale.Category;
import java.util.BitSet;
import java.util.Date;
import java.util.Locale;
/**
* <code>PersianCalendar</code> is a subclass of <code>Calendar</code> that that implements the
* Persian calendar. It is used as the main civil calendar in Iran and Afghanistan, and by Iranians
* and Afghans worldwide.
*
* <p>The Persian calendar is solar, and is similar to the Gregorian calendar in various ways,
* except its leap year rule, which is determined astronomically. The Persian year starts around the
* March equinox.
*
* <p>The modern Persian calendar (used in Iran since 1925 CE and in Afghanistan since 1957 CE), has
* the lengths of the months fixed. The first six months are 31 days each, the next five months are
* 30 days each, and the final month is 29 days in non-leap years and 30 days in leap ones.
* Historically, the lengths of the month differed in different years, but they were finally fixed
* at the times mentioned above. Partial information is available about the historical lengths.
*
* <p>The official rule for determination of the beginning of the Persian year is locale dependent,
* but at the same time, it has not specified a locale. Iranians around the world traditionally
* follow the calendar authorities of Iran, which haven't officially specified the locale. Some
* calendarists use some point in Tehran as the locale, while others have tried the more neutral
* 52.5 degrees east meridian. It is not clear which locale should be used for the Persian calendar
* of Afghanistan, but it is expected that for about one year in every twenty-four years, the Afghan
* calendar may become different from the Iranian one.
*
* <p>The exact locale to be used for the Iranian calendar starts to make a difference at around
* 2090 CE. The specific arithmetic method implemented here, commonly known as the 33-year cycle
* rule, matches the astronomical calendar at least for the whole period that the calendar has been
* both well-defined and official, from 1925 to around 2090 CE. The other commonly known algorithm,
* the 2820-year cycle, has been incorrectly designed to follow the tropical year instead of the
* spring equinoctial year, and fails to match the astronomical one as early as 2025 CE.
*
* <p>This class should not be subclassed.
*
* <p>PersianCalendar usually should be instantiated using {@link
* com.ibm.icu.util.Calendar#getInstance(ULocale)} passing in a <code>ULocale</code> with the tag
* <code>"@calendar=persian"</code>.
*
* @see com.ibm.icu.util.GregorianCalendar
* @see com.ibm.icu.util.Calendar
* @author Roozbeh Pournader
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public class PersianCalendar extends Calendar {
private static final long serialVersionUID = -6727306982975111643L;
// -------------------------------------------------------------------------
// Constants...
// -------------------------------------------------------------------------
private static final int[][] MONTH_COUNT = {
// len len2 st
{31, 31, 0}, // Farvardin
{31, 31, 31}, // Ordibehesht
{31, 31, 62}, // Khordad
{31, 31, 93}, // Tir
{31, 31, 124}, // Mordad
{31, 31, 155}, // Shahrivar
{30, 30, 186}, // Mehr
{30, 30, 216}, // Aban
{30, 30, 246}, // Azar
{30, 30, 276}, // Dey
{30, 30, 306}, // Bahman
{29, 30, 336} // Esfand
// len length of month
// len2 length of month in a leap year
// st days in year before start of month
};
private static final int PERSIAN_EPOCH = 1948320;
private static final class NonLeapYears {
private static final int NON_LEAP_YEARS[] = {
1502, 1601, 1634, 1667, 1700, 1733, 1766, 1799, 1832, 1865, 1898, 1931, 1964, 1997,
2030, 2059,
2063, 2096, 2129, 2158, 2162, 2191, 2195, 2224, 2228, 2257, 2261, 2290, 2294, 2323,
2327, 2356,
2360, 2389, 2393, 2422, 2426, 2455, 2459, 2488, 2492, 2521, 2525, 2554, 2558, 2587,
2591, 2620,
2624, 2653, 2657, 2686, 2690, 2719, 2723, 2748, 2752, 2756, 2781, 2785, 2789, 2818,
2822, 2847,
2851, 2855, 2880, 2884, 2888, 2913, 2917, 2921, 2946, 2950, 2954, 2979, 2983, 2987,
};
private int minYear = NON_LEAP_YEARS[0];
private int maxYear = NON_LEAP_YEARS[NON_LEAP_YEARS.length - 1];
private BitSet offsetYears;
public NonLeapYears() {
offsetYears = new BitSet(maxYear - minYear + 1);
for (int nonLeap : NON_LEAP_YEARS) {
offsetYears.set(nonLeap - minYear);
}
}
public boolean contains(int year) {
return minYear <= year && year <= maxYear && offsetYears.get(year - minYear);
}
}
private static NonLeapYears LEAP_CORRECTION = new NonLeapYears();
// -------------------------------------------------------------------------
// Constructors...
// -------------------------------------------------------------------------
/**
* Constructs a default <code>PersianCalendar</code> using the current time in the default time
* zone with the default <code>FORMAT</code> locale.
*
* @see Category#FORMAT
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar() {
this(TimeZone.getDefault(), ULocale.getDefault(Category.FORMAT));
}
/**
* Constructs a <code>PersianCalendar</code> based on the current time in the given time zone
* with the default <code>FORMAT</code> locale.
*
* @param zone the given time zone.
* @see Category#FORMAT
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar(TimeZone zone) {
this(zone, ULocale.getDefault(Category.FORMAT));
}
/**
* Constructs a <code>PersianCalendar</code> based on the current time in the default time zone
* with the given locale.
*
* @param aLocale the given locale.
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar(Locale aLocale) {
this(TimeZone.forLocaleOrDefault(aLocale), aLocale);
}
/**
* Constructs a <code>PersianCalendar</code> based on the current time in the default time zone
* with the given locale.
*
* @param locale the given ulocale.
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar(ULocale locale) {
this(TimeZone.forULocaleOrDefault(locale), locale);
}
/**
* Constructs a <code>PersianCalendar</code> based on the current time in the given time zone
* with the given locale.
*
* @param zone the given time zone.
* @param aLocale the given locale.
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar(TimeZone zone, Locale aLocale) {
super(zone, aLocale);
setTimeInMillis(System.currentTimeMillis());
}
/**
* Constructs a <code>PersianCalendar</code> based on the current time in the given time zone
* with the given locale.
*
* @param zone the given time zone.
* @param locale the given ulocale.
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar(TimeZone zone, ULocale locale) {
super(zone, locale);
setTimeInMillis(System.currentTimeMillis());
}
/**
* Constructs a <code>PersianCalendar</code> with the given date set in the default time zone
* with the default <code>FORMAT</code> locale.
*
* @param date The date to which the new calendar is set.
* @see Category#FORMAT
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar(Date date) {
super(TimeZone.getDefault(), ULocale.getDefault(Category.FORMAT));
this.setTime(date);
}
/**
* Constructs a <code>PersianCalendar</code> with the given date set in the default time zone
* with the default <code>FORMAT</code> locale.
*
* @param year the value used to set the {@link #YEAR YEAR} time field in the calendar.
* @param month the value used to set the {@link #MONTH MONTH} time field in the calendar. Note
* that the month value is 0-based. e.g., 0 for Farvardin.
* @param date the value used to set the {@link #DATE DATE} time field in the calendar.
* @see Category#FORMAT
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar(int year, int month, int date) {
super(TimeZone.getDefault(), ULocale.getDefault(Category.FORMAT));
this.set(Calendar.YEAR, year);
this.set(Calendar.MONTH, month);
this.set(Calendar.DATE, date);
}
/**
* Constructs a <code>PersianCalendar</code> with the given date and time set for the default
* time zone with the default <code>FORMAT</code> locale.
*
* @param year the value used to set the {@link #YEAR YEAR} time field in the calendar.
* @param month the value used to set the {@link #MONTH MONTH} time field in the calendar. Note
* that the month value is 0-based. e.g., 0 for Farvardin.
* @param date the value used to set the {@link #DATE DATE} time field in the calendar.
* @param hour the value used to set the {@link #HOUR_OF_DAY HOUR_OF_DAY} time field in the
* calendar.
* @param minute the value used to set the {@link #MINUTE MINUTE} time field in the calendar.
* @param second the value used to set the {@link #SECOND SECOND} time field in the calendar.
* @see Category#FORMAT
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
public PersianCalendar(int year, int month, int date, int hour, int minute, int second) {
super(TimeZone.getDefault(), ULocale.getDefault(Category.FORMAT));
this.set(Calendar.YEAR, year);
this.set(Calendar.MONTH, month);
this.set(Calendar.DATE, date);
this.set(Calendar.HOUR_OF_DAY, hour);
this.set(Calendar.MINUTE, minute);
this.set(Calendar.SECOND, second);
}
// -------------------------------------------------------------------------
// Minimum / Maximum access functions
// -------------------------------------------------------------------------
private static final int LIMITS[][] = {
// Minimum Greatest Least Maximum
// Minimum Maximum
{0, 0, 0, 0}, // ERA
{-5000000, -5000000, 5000000, 5000000}, // YEAR
{0, 0, 11, 11}, // MONTH
{1, 1, 52, 53}, // WEEK_OF_YEAR
{
/* */
}, // WEEK_OF_MONTH
{1, 1, 29, 31}, // DAY_OF_MONTH
{1, 1, 365, 366}, // DAY_OF_YEAR
{
/* */
}, // DAY_OF_WEEK
{-1, -1, 5, 5}, // DAY_OF_WEEK_IN_MONTH
{
/* */
}, // AM_PM
{
/* */
}, // HOUR
{
/* */
}, // HOUR_OF_DAY
{
/* */
}, // MINUTE
{
/* */
}, // SECOND
{
/* */
}, // MILLISECOND
{
/* */
}, // ZONE_OFFSET
{
/* */
}, // DST_OFFSET
{-5000000, -5000000, 5000000, 5000000}, // YEAR_WOY
{
/* */
}, // DOW_LOCAL
{-5000000, -5000000, 5000000, 5000000}, // EXTENDED_YEAR
{
/* */
}, // JULIAN_DAY
{
/* */
}, // MILLISECONDS_IN_DAY
{
/* */
}, // IS_LEAP_MONTH
{0, 0, 11, 11}, // ORDINAL_MONTH
};
/**
* @internal
* @deprecated This API is ICU internal only.
*/
@Override
@Deprecated
protected int handleGetLimit(int field, int limitType) {
return LIMITS[field][limitType];
}
// -------------------------------------------------------------------------
// Assorted calculation utilities
//
/** Determine whether a year is a leap year in the Persian calendar */
private static final boolean isLeapYear(int year) {
if (LEAP_CORRECTION.contains(year)) {
return false;
}
if (LEAP_CORRECTION.contains(year - 1)) {
return true;
}
int[] remainder = new int[1];
floorDivide(25 * year + 11, 33, remainder);
return remainder[0] < 8;
}
// ----------------------------------------------------------------------
// Calendar framework
// ----------------------------------------------------------------------
/**
* Return the length (in days) of the given month.
*
* @param extendedYear The Persian year
* @param month The Persian month, 0-based
* @internal
* @deprecated This API is ICU internal only.
*/
@Override
@Deprecated
protected int handleGetMonthLength(int extendedYear, int month) {
// If the month is out of range, adjust it into range, and
// modify the extended year value accordingly.
if (month < 0 || month > 11) {
int[] rem = new int[1];
extendedYear += floorDivide(month, 12, rem);
month = rem[0];
}
return MONTH_COUNT[month][isLeapYear(extendedYear) ? 1 : 0];
}
/**
* Return the number of days in the given Persian year
*
* @internal
* @deprecated This API is ICU internal only.
*/
@Override
@Deprecated
protected int handleGetYearLength(int extendedYear) {
return isLeapYear(extendedYear) ? 366 : 365;
}
// -------------------------------------------------------------------------
// Functions for converting from field values to milliseconds....
// -------------------------------------------------------------------------
/**
* Return JD of start of given month/year
*
* @internal
* @deprecated This API is ICU internal only.
*/
@Override
@Deprecated
protected int handleComputeMonthStart(int eyear, int month, boolean useMonth) {
// If the month is out of range, adjust it into range, and
// modify the extended year value accordingly.
if (month < 0 || month > 11) {
int[] rem = new int[1];
eyear += floorDivide(month, 12, rem);
month = rem[0];
}
long julianDay = PERSIAN_EPOCH - 1L + firstJulianOfYear(eyear);
if (month != 0) {
julianDay += MONTH_COUNT[month][2];
}
return (int) julianDay;
}
// -------------------------------------------------------------------------
// Functions for converting from milliseconds to field values
// -------------------------------------------------------------------------
/**
* @internal
* @deprecated This API is ICU internal only.
*/
@Override
@Deprecated
protected int handleGetExtendedYear() {
int year;
if (newerField(EXTENDED_YEAR, YEAR) == EXTENDED_YEAR) {
year = internalGet(EXTENDED_YEAR, 1); // Default to year 1
} else {
year = internalGet(YEAR, 1); // Default to year 1
}
return year;
}
private static long firstJulianOfYear(int year) {
long julianDay = 365L * (year - 1L) + floorDivide(8L * year + 21, 33L);
if (LEAP_CORRECTION.contains(year - 1)) {
julianDay--;
}
return julianDay;
}
/**
* Override Calendar to compute several fields specific to the Persian calendar system. These
* are:
*
* <ul>
* <li>ERA
* <li>YEAR
* <li>MONTH
* <li>DAY_OF_MONTH
* <li>DAY_OF_YEAR
* <li>EXTENDED_YEAR
* </ul>
*
* The DAY_OF_WEEK and DOW_LOCAL fields are already set when this method is called.
*
* @internal
* @deprecated This API is ICU internal only.
*/
@Override
@Deprecated
protected void handleComputeFields(int julianDay) {
int year, month, dayOfMonth, dayOfYear;
long daysSinceEpoch = julianDay - PERSIAN_EPOCH;
year = 1 + (int) floorDivide(33 * daysSinceEpoch + 3, 12053);
long farvardin1 = firstJulianOfYear(year);
dayOfYear = (int) (daysSinceEpoch - farvardin1); // 0-based
if (dayOfYear == 365 && LEAP_CORRECTION.contains(year)) {
year++;
dayOfYear = 0;
}
if (dayOfYear < 216) { // Compute 0-based month
month = dayOfYear / 31;
} else {
month = (dayOfYear - 6) / 30;
}
++dayOfYear; // Make it 1-based now
dayOfMonth = dayOfYear - MONTH_COUNT[month][2];
internalSet(ERA, 0);
internalSet(YEAR, year);
internalSet(EXTENDED_YEAR, year);
internalSet(MONTH, month);
internalSet(ORDINAL_MONTH, month);
internalSet(DAY_OF_MONTH, dayOfMonth);
internalSet(DAY_OF_YEAR, dayOfYear);
}
private static final int PERSIAN_CALENDAR_RELATED_YEAR_DIFFERENCE = 622;
/**
* @internal
* @deprecated This API is ICU internal only.
*/
@Override
@Deprecated
protected final int getRelatedYearDifference() {
return PERSIAN_CALENDAR_RELATED_YEAR_DIFFERENCE;
}
/**
* {@inheritDoc}
*
* @internal
* @deprecated This API is ICU internal only.
*/
@Override
@Deprecated
public String getType() {
return "persian";
}
}