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Implements the Umm Al-Qura calendar system in Java language.
/*
* Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* Copyright (c) 2012, 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
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Modified by Mouaffak A. Sarhan
* Removed unused methods.
*/
package com.github.msarhan.ummalqura.calendar;
import java.io.InputStream;
import java.io.Serializable;
import java.util.*;
class HijrahChronology implements Serializable {
/**
* Serialization version.
*/
private static final long serialVersionUID = 3127340209035924785L;
/**
* Singleton instance of the Islamic Umm Al-Qura calendar of Saudi Arabia.
* Other Hijrah chronology variants may be available from
*/
public static final HijrahChronology INSTANCE;
/**
* Flag to indicate the initialization of configuration data is complete.
*
* @see #checkCalendarInit()
*/
private transient volatile boolean initComplete;
/**
* Array of epoch days indexed by Hijrah Epoch month.
* Computed by {@link #loadCalendarData}.
*/
private transient int[] hijrahEpochMonthStartDays;
/**
* The minimum epoch day of this Hijrah calendar.
* Computed by {@link #loadCalendarData}.
*/
private transient int minEpochDay;
/**
* The maximum epoch day for which calendar data is available.
* Computed by {@link #loadCalendarData}.
*/
private transient int maxEpochDay;
/**
* The minimum epoch month.
* Computed by {@link #loadCalendarData}.
*/
private transient int hijrahStartEpochMonth;
/**
* The minimum length of a month.
* Computed by {@link #createEpochMonths}.
*/
private transient int minMonthLength;
/**
* The maximum length of a month.
* Computed by {@link #createEpochMonths}.
*/
private transient int maxMonthLength;
/**
* The minimum length of a year in days.
* Computed by {@link #createEpochMonths}.
*/
private transient int minYearLength;
/**
* The maximum length of a year in days.
* Computed by {@link #createEpochMonths}.
*/
private transient int maxYearLength;
/**
* Prefix of property names for Hijrah calendar variants.
*/
private static final String PROP_PREFIX = "calendar.hijrah.";
/**
* Suffix of property names containing the calendar type of a variant.
*/
private static final String PROP_TYPE_SUFFIX = ".type";
static {
try {
INSTANCE = new HijrahChronology();
} catch (Exception ex) {
throw new RuntimeException("Unable to initialize Hijrah-umalqura calendar", ex.getCause());
}
}
/**
* Create a HijrahChronology for the named variant.
* The resource and calendar type are retrieved from properties
* in the {@code calendars.properties}.
* The property names are {@code "calendar.hijrah." + id}
* and {@code "calendar.hijrah." + id + ".type"}
*
* @throws DateTimeException if the calendar type is missing from the properties file.
* @throws IllegalArgumentException if the id is empty
*/
private HijrahChronology() throws DateTimeException {
}
/**
* Check and ensure that the calendar data has been initialized.
* The initialization check is performed at the boundary between
* public and package methods. If a public calls another public method
* a check is not necessary in the caller.
* The constructors of HijrahDate call {@link #getEpochDay} or
* {@link #getHijrahDateInfo} so every call from HijrahDate to a
* HijrahChronology via package private methods has been checked.
*
* @throws DateTimeException if the calendar data configuration is
* malformed or IOExceptions occur loading the data
*/
private void checkCalendarInit() {
// Keep this short so it can be inlined for performance
if (!initComplete) {
loadCalendarData();
initComplete = true;
}
}
//-----------------------------------------------------------------------
public boolean isLeapYear(long prolepticYear) {
checkCalendarInit();
if (prolepticYear < getMinimumYear() || prolepticYear > getMaximumYear()) {
return false;
}
int len = getYearLength((int) prolepticYear);
return (len > 354);
}
/**
* Check the validity of a year.
*
* @param prolepticYear the year to check
*/
int checkValidYear(long prolepticYear) {
if (prolepticYear < getMinimumYear() || prolepticYear > getMaximumYear()) {
throw new DateTimeException("Invalid Hijrah year: " + prolepticYear);
}
return (int) prolepticYear;
}
void checkValidDayOfYear(int dayOfYear) {
if (dayOfYear < 1 || dayOfYear > getMaximumDayOfYear()) {
throw new DateTimeException("Invalid Hijrah day of year: " + dayOfYear);
}
}
void checkValidMonth(int month) {
if (month < 1 || month > 12) {
throw new DateTimeException("Invalid Hijrah month: " + month);
}
}
//-----------------------------------------------------------------------
/**
* Returns an array containing the Hijrah year, month and day
* computed from the epoch day.
*
* @param epochDay the EpochDay
* @return int[0] = YEAR, int[1] = MONTH, int[2] = DATE
*/
int[] getHijrahDateInfo(int epochDay) {
checkCalendarInit(); // ensure that the chronology is initialized
if (epochDay < minEpochDay || epochDay >= maxEpochDay) {
throw new DateTimeException("Hijrah date out of range");
}
int epochMonth = epochDayToEpochMonth(epochDay);
int year = epochMonthToYear(epochMonth);
int month = epochMonthToMonth(epochMonth);
int day1 = epochMonthToEpochDay(epochMonth);
int date = epochDay - day1; // epochDay - dayOfEpoch(year, month);
int dateInfo[] = new int[3];
dateInfo[0] = year;
dateInfo[1] = month; // change to 1-based.
dateInfo[2] = date + 1; // change to 1-based.
return dateInfo;
}
/**
* Return the epoch day computed from Hijrah year, month, and day.
*
* @param prolepticYear the year to represent, 0-origin
* @param monthOfYear the month-of-year to represent, 1-origin
* @param dayOfMonth the day-of-month to represent, 1-origin
* @return the epoch day
*/
long getEpochDay(int prolepticYear, int monthOfYear, int dayOfMonth) {
checkCalendarInit(); // ensure that the chronology is initialized
checkValidMonth(monthOfYear);
int epochMonth = yearToEpochMonth(prolepticYear) + (monthOfYear - 1);
if (epochMonth < 0 || epochMonth >= hijrahEpochMonthStartDays.length) {
throw new DateTimeException("Invalid Hijrah date, year: " +
prolepticYear + ", month: " + monthOfYear);
}
if (dayOfMonth < 1 || dayOfMonth > getMonthLength(prolepticYear, monthOfYear)) {
throw new DateTimeException("Invalid Hijrah day of month: " + dayOfMonth);
}
return epochMonthToEpochDay(epochMonth) + (dayOfMonth - 1);
}
/**
* Returns day of year for the year and month.
*
* @param prolepticYear a proleptic year
* @param month a month, 1-origin
* @return the day of year, 1-origin
*/
int getDayOfYear(int prolepticYear, int month) {
return yearMonthToDayOfYear(prolepticYear, (month - 1));
}
/**
* Returns month length for the year and month.
*
* @param prolepticYear a proleptic year
* @param monthOfYear a month, 1-origin.
* @return the length of the month
*/
int getMonthLength(int prolepticYear, int monthOfYear) {
int epochMonth = yearToEpochMonth(prolepticYear) + (monthOfYear - 1);
if (epochMonth < 0 || epochMonth >= hijrahEpochMonthStartDays.length) {
throw new DateTimeException("Invalid Hijrah date, year: " +
prolepticYear + ", month: " + monthOfYear);
}
return epochMonthLength(epochMonth);
}
/**
* Returns year length.
* Note: The 12th month must exist in the data.
*
* @param prolepticYear a proleptic year
* @return year length in days
*/
int getYearLength(int prolepticYear) {
return yearMonthToDayOfYear(prolepticYear, 12);
}
/**
* Return the minimum supported Hijrah year.
*
* @return the minimum
*/
int getMinimumYear() {
return epochMonthToYear(0);
}
/**
* Return the maximum supported Hijrah ear.
*
* @return the minimum
*/
int getMaximumYear() {
return epochMonthToYear(hijrahEpochMonthStartDays.length - 1) - 1;
}
/**
* Returns maximum day-of-month.
*
* @return maximum day-of-month
*/
int getMaximumMonthLength() {
return maxMonthLength;
}
/**
* Returns smallest maximum day-of-month.
*
* @return smallest maximum day-of-month
*/
int getMinimumMonthLength() {
return minMonthLength;
}
/**
* Returns maximum day-of-year.
*
* @return maximum day-of-year
*/
int getMaximumDayOfYear() {
return maxYearLength;
}
/**
* Returns smallest maximum day-of-year.
*
* @return smallest maximum day-of-year
*/
int getSmallestMaximumDayOfYear() {
return minYearLength;
}
/**
* Returns the epochMonth found by locating the epochDay in the table. The
* epochMonth is the index in the table
*
* @param epochDay epochDay
* @return The index of the element of the start of the month containing the
* epochDay.
*/
private int epochDayToEpochMonth(int epochDay) {
// binary search
int ndx = Arrays.binarySearch(hijrahEpochMonthStartDays, epochDay);
if (ndx < 0) {
ndx = -ndx - 2;
}
return ndx;
}
/**
* Returns the year computed from the epochMonth
*
* @param epochMonth the epochMonth
* @return the Hijrah Year
*/
private int epochMonthToYear(int epochMonth) {
return (epochMonth + hijrahStartEpochMonth) / 12;
}
/**
* Returns the epochMonth for the Hijrah Year.
*
* @param year the HijrahYear
* @return the epochMonth for the beginning of the year.
*/
private int yearToEpochMonth(int year) {
return (year * 12) - hijrahStartEpochMonth;
}
/**
* Returns the Hijrah month from the epochMonth.
*
* @param epochMonth the epochMonth
* @return the month of the Hijrah Year
*/
private int epochMonthToMonth(int epochMonth) {
return (epochMonth + hijrahStartEpochMonth) % 12;
}
/**
* Returns the epochDay for the start of the epochMonth.
*
* @param epochMonth the epochMonth
* @return the epochDay for the start of the epochMonth.
*/
private int epochMonthToEpochDay(int epochMonth) {
return hijrahEpochMonthStartDays[epochMonth];
}
/**
* Returns the day of year for the requested HijrahYear and month.
*
* @param prolepticYear the Hijrah year
* @param month the Hijrah month
* @return the day of year for the start of the month of the year
*/
private int yearMonthToDayOfYear(int prolepticYear, int month) {
int epochMonthFirst = yearToEpochMonth(prolepticYear);
return epochMonthToEpochDay(epochMonthFirst + month)
- epochMonthToEpochDay(epochMonthFirst);
}
/**
* Returns the length of the epochMonth. It is computed from the start of
* the following month minus the start of the requested month.
*
* @param epochMonth the epochMonth; assumed to be within range
* @return the length in days of the epochMonth
*/
private int epochMonthLength(int epochMonth) {
// The very last entry in the epochMonth table is not the start of a month
return hijrahEpochMonthStartDays[epochMonth + 1]
- hijrahEpochMonthStartDays[epochMonth];
}
private static final String KEY_ID = "id";
private static final String KEY_TYPE = "type";
private static final String KEY_VERSION = "version";
private static final String KEY_ISO_START = "iso-start";
/**
* Return the configuration properties from the resource.
*
* The default location of the variant configuration resource is:
*
* "$java.home/lib/" + resource-name
*
*
* @return a Properties containing the properties read from the resource.
* @throws Exception if access to the property resource fails
*/
private static Properties readConfigProperties() throws Exception {
Properties props = new Properties();
try (InputStream is = HijrahChronology.class.getResourceAsStream("/com/github/msarhan/ummalqura/calendar/hijrah-config.properties")) {
props.load(is);
}
return props;
}
/**
* Loads and processes the Hijrah calendar properties file for this calendarType.
* The starting Hijrah date and the corresponding ISO date are
* extracted and used to calculate the epochDate offset.
* The version number is identified and ignored.
* Everything else is the data for a year with containing the length of each
* of 12 months.
*
* @throws DateTimeException if initialization of the calendar data from the
* resource fails
*/
private void loadCalendarData() {
try {
Properties props = readConfigProperties();
Map years = new HashMap<>();
int minYear = Integer.MAX_VALUE;
int maxYear = Integer.MIN_VALUE;
String version = null;
int isoStart = 0;
for (Map.Entry entry : props.entrySet()) {
String key = (String) entry.getKey();
switch (key) {
case KEY_VERSION:
version = (String) entry.getValue();
break;
case KEY_ISO_START: {
int[] ymd = parseYMD((String) entry.getValue());
isoStart = (int) toIsoEpochDay(ymd[0], ymd[1], ymd[2]);
break;
}
case KEY_TYPE:
case KEY_ID:
break;
default:
try {
// Everything else is either a year or invalid
int year = Integer.parseInt(key);
int[] months = parseMonths((String) entry.getValue());
years.put(year, months);
maxYear = Math.max(maxYear, year);
minYear = Math.min(minYear, year);
} catch (NumberFormatException nfe) {
throw new IllegalArgumentException("bad key: " + key);
}
}
}
if (version == null || version.isEmpty()) {
throw new IllegalArgumentException("Configuration does not contain a version");
}
if (isoStart == 0) {
throw new IllegalArgumentException("Configuration does not contain a ISO start date");
}
// Now create and validate the array of epochDays indexed by epochMonth
hijrahStartEpochMonth = minYear * 12;
minEpochDay = isoStart;
hijrahEpochMonthStartDays = createEpochMonths(minEpochDay, minYear, maxYear, years);
maxEpochDay = hijrahEpochMonthStartDays[hijrahEpochMonthStartDays.length - 1];
// Compute the min and max year length in days.
for (int year = minYear; year < maxYear; year++) {
int length = getYearLength(year);
minYearLength = Math.min(minYearLength, length);
maxYearLength = Math.max(maxYearLength, length);
}
} catch (Exception ex) {
throw new DateTimeException("Unable to initialize HijrahCalendar", ex);
}
}
/**
* Converts the map of year to month lengths ranging from minYear to maxYear
* into a linear contiguous array of epochDays. The index is the hijrahMonth
* computed from year and month and offset by minYear. The value of each
* entry is the epochDay corresponding to the first day of the month.
*
* @param minYear The minimum year for which data is provided
* @param maxYear The maximum year for which data is provided
* @param years a Map of year to the array of 12 month lengths
* @return array of epochDays for each month from min to max
*/
private int[] createEpochMonths(int epochDay, int minYear, int maxYear, Map years) {
// Compute the size for the array of dates
int numMonths = (maxYear - minYear + 1) * 12 + 1;
// Initialize the running epochDay as the corresponding ISO Epoch day
int epochMonth = 0; // index into array of epochMonths
int[] epochMonths = new int[numMonths];
minMonthLength = Integer.MAX_VALUE;
maxMonthLength = Integer.MIN_VALUE;
// Only whole years are valid, any zero's in the array are illegal
for (int year = minYear; year <= maxYear; year++) {
int[] months = years.get(year);// must not be gaps
for (int month = 0; month < 12; month++) {
int length = months[month];
epochMonths[epochMonth++] = epochDay;
if (length < 29 || length > 32) {
throw new IllegalArgumentException("Invalid month length in year: " + minYear);
}
epochDay += length;
minMonthLength = Math.min(minMonthLength, length);
maxMonthLength = Math.max(maxMonthLength, length);
}
}
// Insert the final epochDay
epochMonths[epochMonth++] = epochDay;
if (epochMonth != epochMonths.length) {
throw new IllegalStateException("Did not fill epochMonths exactly: ndx = " + epochMonth
+ " should be " + epochMonths.length);
}
return epochMonths;
}
/**
* Parses the 12 months lengths from a property value for a specific year.
*
* @param line the value of a year property
* @return an array of int[12] containing the 12 month lengths
* @throws IllegalArgumentException if the number of months is not 12
* @throws NumberFormatException if the 12 tokens are not numbers
*/
private int[] parseMonths(String line) {
int[] months = new int[12];
String[] numbers = line.split("\\s");
if (numbers.length != 12) {
throw new IllegalArgumentException("wrong number of months on line: " + Arrays.toString(numbers) + "; count: " + numbers.length);
}
for (int i = 0; i < 12; i++) {
try {
months[i] = Integer.parseInt(numbers[i]);
} catch (NumberFormatException nfe) {
throw new IllegalArgumentException("bad key: " + numbers[i]);
}
}
return months;
}
/**
* Parse yyyy-MM-dd into a 3 element array [yyyy, mm, dd].
*
* @param string the input string
* @return the 3 element array with year, month, day
*/
private int[] parseYMD(String string) {
// yyyy-MM-dd
string = string.trim();
try {
if (string.charAt(4) != '-' || string.charAt(7) != '-') {
throw new IllegalArgumentException("date must be yyyy-MM-dd");
}
int[] ymd = new int[3];
ymd[0] = Integer.parseInt(string.substring(0, 4));
ymd[1] = Integer.parseInt(string.substring(5, 7));
ymd[2] = Integer.parseInt(string.substring(8, 10));
return ymd;
} catch (NumberFormatException ex) {
throw new IllegalArgumentException("date must be yyyy-MM-dd", ex);
}
}
// -------------------------
private static final int DAYS_PER_CYCLE = 146097;
static final long DAYS_0000_TO_1970 = (DAYS_PER_CYCLE * 5L) - (30L * 365L + 7L);
public static Date fromIsoEpochDay(long epochDay) {
long zeroDay = epochDay + DAYS_0000_TO_1970;
// find the march-based year
zeroDay -= 60; // adjust to 0000-03-01 so leap day is at end of four year cycle
long adjust = 0;
if (zeroDay < 0) {
// adjust negative years to positive for calculation
long adjustCycles = (zeroDay + 1) / DAYS_PER_CYCLE - 1;
adjust = adjustCycles * 400;
zeroDay += -adjustCycles * DAYS_PER_CYCLE;
}
long yearEst = (400 * zeroDay + 591) / DAYS_PER_CYCLE;
long doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
if (doyEst < 0) {
// fix estimate
yearEst--;
doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
}
yearEst += adjust; // reset any negative year
int marchDoy0 = (int) doyEst;
// convert march-based values back to january-based
int marchMonth0 = (marchDoy0 * 5 + 2) / 153;
int month = (marchMonth0 + 2) % 12 + 1;
int dom = marchDoy0 - (marchMonth0 * 306 + 5) / 10 + 1;
yearEst += marchMonth0 / 10;
return new GregorianCalendar((int) yearEst, month - 1, dom).getTime();
}
public long toIsoEpochDay(int year, int month, int day) {
long y = year;
long m = month;
long total = 0;
total += 365 * y;
if (y >= 0) {
total += (y + 3) / 4 - (y + 99) / 100 + (y + 399) / 400;
} else {
total -= y / -4 - y / -100 + y / -400;
}
total += ((367 * m - 362) / 12);
total += day - 1;
if (m > 2) {
total--;
if (!isIsoLeapYear(year)) {
total--;
}
}
return total - DAYS_0000_TO_1970;
}
public boolean isIsoLeapYear(long prolepticYear) {
return ((prolepticYear & 3) == 0) && ((prolepticYear % 100) != 0 || (prolepticYear % 400) == 0);
}
static int[] toHijri(Date date) {
final Calendar calendar = GregorianCalendar.getInstance();
calendar.setTime(date);
return INSTANCE.getHijrahDateInfo((int) INSTANCE.toIsoEpochDay(
calendar.get(Calendar.YEAR),
calendar.get(Calendar.MONTH) + 1,
calendar.get(Calendar.DAY_OF_MONTH)
));
}
static int[] toGregorian(int hYear, int hMonth, int hDay) {
final Date date = HijrahChronology.fromIsoEpochDay(INSTANCE.getEpochDay(hYear, hMonth + 1, hDay));
final Calendar calendar = GregorianCalendar.getInstance();
calendar.setTime(date);
return new int[]{
calendar.get(Calendar.YEAR),
calendar.get(Calendar.MONTH),
calendar.get(Calendar.DAY_OF_MONTH)
};
}
static int getDaysInMonth(int year, int month) {
return INSTANCE.getMonthLength(year, month);
}
}