1810 lines
68 KiB
C++
1810 lines
68 KiB
C++
/*
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********************************************************************************
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* *
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* COPYRIGHT: *
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* (C) Copyright Taligent, Inc., 1997 *
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* (C) Copyright International Business Machines Corporation, 1997-1998 *
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* Copyright (C) 1999 Alan Liu and others. All rights reserved. *
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* Licensed Material - Program-Property of IBM - All Rights Reserved. *
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* US Government Users Restricted Rights - Use, duplication, or disclosure *
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* restricted by GSA ADP Schedule Contract with IBM Corp. *
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* *
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********************************************************************************
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*
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* File GREGOCAL.CPP
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*
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* Modification History:
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*
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* Date Name Description
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* 02/05/97 clhuang Creation.
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* 03/28/97 aliu Made highly questionable fix to computeFields to
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* handle DST correctly.
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* 04/22/97 aliu Cleaned up code drastically. Added monthLength().
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* Finished unimplemented parts of computeTime() for
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* week-based date determination. Removed quetionable
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* fix and wrote correct fix for computeFields() and
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* daylight time handling. Rewrote inDaylightTime()
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* and computeFields() to handle sensitive Daylight to
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* Standard time transitions correctly.
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* 05/08/97 aliu Added code review changes. Fixed isLeapYear() to
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* not cutover.
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* 08/12/97 aliu Added equivalentTo. Misc other fixes. Updated
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* add() from Java source.
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* 07/28/98 stephen Sync up with JDK 1.2
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* 09/14/98 stephen Changed type of kOneDay, kOneWeek to double.
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* Fixed bug in roll()
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* 10/15/99 aliu Fixed j31, incorrect WEEK_OF_YEAR computation.
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* 10/15/99 aliu Fixed j32, cannot set date to Feb 29 2000 AD.
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* {JDK bug 4210209 4209272}
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********************************************************************************
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*/
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#ifndef _GREGOCAL
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#include "gregocal.h"
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#endif
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// *****************************************************************************
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// class GregorianCalendar
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// *****************************************************************************
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const int32_t GregorianCalendar::kJan1_1JulianDay = 1721426; // January 1, year 1 (Gregorian)
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/**
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* Note that the Julian date used here is not a true Julian date, since
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* it is measured from midnight, not noon. This value is the Julian
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* day number of January 1, 1970 (Gregorian calendar) at noon UTC. [LIU]
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*/
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const int32_t GregorianCalendar::kEpochStartAsJulianDay = 2440588; // January 1, 1970 (Gregorian)
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const int32_t GregorianCalendar::kEpochYear = 1970;
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const int32_t GregorianCalendar::kNumDays[]
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= {0,31,59,90,120,151,181,212,243,273,304,334}; // 0-based, for day-in-year
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const int32_t GregorianCalendar::kLeapNumDays[]
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= {0,31,60,91,121,152,182,213,244,274,305,335}; // 0-based, for day-in-year
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const int32_t GregorianCalendar::kMonthLength[]
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= {31,28,31,30,31,30,31,31,30,31,30,31}; // 0-based
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const int32_t GregorianCalendar::kLeapMonthLength[]
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= {31,29,31,30,31,30,31,31,30,31,30,31}; // 0-based
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// Useful millisecond constants
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const int32_t GregorianCalendar::kOneSecond = 1000;
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const int32_t GregorianCalendar::kOneMinute = 60 * kOneSecond; // 60,000
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const int32_t GregorianCalendar::kOneHour = 60 * kOneMinute; // 3,600,000
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const double GregorianCalendar::kOneDay = 24.0 * kOneHour; // 86,400,000
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const double GregorianCalendar::kOneWeek = 7.0 * kOneDay; // 604,800,000
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// These numbers are 2^52 - 1, the largest allowable mantissa in a 64-bit double
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// with a 0 exponent. These are the absolute largest numbers for millis that
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// this calendar will handle reliably. It will work for larger values, however.
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// The problem is that, once the exponent is not 0, the calendar will jump.
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// When translated into a year, LATEST_SUPPORTED_MILLIS corresponds to 144,683 AD
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// and EARLIEST_SUPPORTED_MILLIS corresponds to 140,742 BC
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const UDate GregorianCalendar::EARLIEST_SUPPORTED_MILLIS = - 4503599627370495.0;
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const UDate GregorianCalendar::LATEST_SUPPORTED_MILLIS = 4503599627370495.0;
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/*
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* <pre>
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* Greatest Least
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* Field name Minimum Minimum Maximum Maximum
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* ---------- ------- ------- ------- -------
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* ERA 0 0 1 1
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* YEAR 1 1 140742 144683
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* MONTH 0 0 11 11
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* WEEK_OF_YEAR 1 1 52 53
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* WEEK_OF_MONTH 0 0 4 6
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* DAY_OF_MONTH 1 1 28 31
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* DAY_OF_YEAR 1 1 365 366
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* DAY_OF_WEEK 1 1 7 7
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* DAY_OF_WEEK_IN_MONTH -1 -1 4 6
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* AM_PM 0 0 1 1
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* HOUR 0 0 11 11
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* HOUR_OF_DAY 0 0 23 23
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* MINUTE 0 0 59 59
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* SECOND 0 0 59 59
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* MILLISECOND 0 0 999 999
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* ZONE_OFFSET -12* -12* 12* 12*
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* DST_OFFSET 0 0 1* 1*
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* </pre>
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* (*) In units of one-hour
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*/
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const int32_t GregorianCalendar::kMinValues[] = {
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0,1,0,1,0,1,1,1,-1,0,0,0,0,0,0,-12*U_MILLIS_PER_HOUR,0
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};
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const int32_t GregorianCalendar::kLeastMaxValues[] = {
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1,140742,11,52,4,28,365,7,4,1,11,23,59,59,999,12*U_MILLIS_PER_HOUR,1*U_MILLIS_PER_HOUR
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};
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const int32_t GregorianCalendar::kMaxValues[] = {
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1,144683,11,53,6,31,366,7,6,1,11,23,59,59,999,12*U_MILLIS_PER_HOUR,1*U_MILLIS_PER_HOUR
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};
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char GregorianCalendar::fgClassID = 0; // Value is irrelevant
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// 00:00:00 UTC, October 15, 1582, expressed in ms from the epoch.
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// Note that only Italy and other Catholic countries actually
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// observed this cutover. Most other countries followed in
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// the next few centuries, some as late as 1928. [LIU]
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// in Java, -12219292800000L
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//const UDate GregorianCalendar::kPapalCutover = -12219292800000L;
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const UDate GregorianCalendar::kPapalCutover = (2299161.0 - kEpochStartAsJulianDay) * kOneDay;
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(UErrorCode& status)
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: Calendar(TimeZone::createDefault(), Locale::getDefault(), status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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setTimeInMillis(getNow(), status);
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(TimeZone* zone, UErrorCode& status)
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: Calendar(zone, Locale::getDefault(), status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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setTimeInMillis(getNow(), status);
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(const TimeZone& zone, UErrorCode& status)
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: Calendar(zone, Locale::getDefault(), status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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setTimeInMillis(getNow(), status);
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(const Locale& aLocale, UErrorCode& status)
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: Calendar(TimeZone::createDefault(), aLocale, status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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setTimeInMillis(getNow(), status);
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(TimeZone* zone, const Locale& aLocale,
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UErrorCode& status)
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: Calendar(zone, aLocale, status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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setTimeInMillis(getNow(), status);
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(const TimeZone& zone, const Locale& aLocale,
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UErrorCode& status)
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: Calendar(zone, aLocale, status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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setTimeInMillis(getNow(), status);
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date,
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UErrorCode& status)
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: Calendar(TimeZone::createDefault(), Locale::getDefault(), status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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set(Calendar::ERA, AD);
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set(Calendar::YEAR, year);
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set(Calendar::MONTH, month);
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set(Calendar::DATE, date);
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date,
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int32_t hour, int32_t minute, UErrorCode& status)
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: Calendar(TimeZone::createDefault(), Locale::getDefault(), status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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set(Calendar::ERA, AD);
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set(Calendar::YEAR, year);
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set(Calendar::MONTH, month);
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set(Calendar::DATE, date);
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set(Calendar::HOUR_OF_DAY, hour);
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set(Calendar::MINUTE, minute);
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(int32_t year, int32_t month, int32_t date,
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int32_t hour, int32_t minute, int32_t second,
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UErrorCode& status)
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: Calendar(TimeZone::createDefault(), Locale::getDefault(), status),
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fGregorianCutover(kPapalCutover),
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fNormalizedGregorianCutover(fGregorianCutover),
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fGregorianCutoverYear(1582)
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{
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set(Calendar::ERA, AD);
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set(Calendar::YEAR, year);
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set(Calendar::MONTH, month);
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set(Calendar::DATE, date);
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set(Calendar::HOUR_OF_DAY, hour);
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set(Calendar::MINUTE, minute);
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set(Calendar::SECOND, second);
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}
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// -------------------------------------
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GregorianCalendar::~GregorianCalendar()
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{
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}
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// -------------------------------------
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GregorianCalendar::GregorianCalendar(const GregorianCalendar &source)
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: Calendar(source),
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fGregorianCutover(source.fGregorianCutover),
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fNormalizedGregorianCutover(source.fNormalizedGregorianCutover),
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fGregorianCutoverYear(source.fGregorianCutoverYear)
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{
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}
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// -------------------------------------
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Calendar* GregorianCalendar::clone() const
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{
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return new GregorianCalendar(*this);
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}
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// -------------------------------------
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GregorianCalendar &
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GregorianCalendar::operator=(const GregorianCalendar &right)
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{
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if (this != &right)
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{
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Calendar::operator=(right);
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fGregorianCutover = right.fGregorianCutover;
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fNormalizedGregorianCutover = right.fNormalizedGregorianCutover;
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fGregorianCutoverYear = right.fGregorianCutoverYear;
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}
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return *this;
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}
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// -------------------------------------
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bool_t
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GregorianCalendar::operator==(const Calendar& that) const
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{
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GregorianCalendar* other = (GregorianCalendar*)&that;
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return (this == &that) ||
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(Calendar::operator==(that) &&
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getDynamicClassID() == that.getDynamicClassID() &&
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fGregorianCutover == other->fGregorianCutover);
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}
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// {sfb} API change?
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bool_t GregorianCalendar::equivalentTo(const Calendar& other) const
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{
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// Calendar override.
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// Return true if another Calendar object is equivalent to this one. An equivalent
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// Calendar will behave exactly as this one does, but may be set to a different time.
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return Calendar::equivalentTo(other) &&
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fGregorianCutover == ((GregorianCalendar*)&other)->fGregorianCutover;
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}
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// -------------------------------------
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void
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GregorianCalendar::setGregorianChange(UDate date, UErrorCode& status)
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{
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if (U_FAILURE(status))
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return;
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fGregorianCutover = date;
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// Precompute two internal variables which we use to do the actual
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// cutover computations. These are the normalized cutover, which is the
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// midnight at or before the cutover, and the cutover year. The
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// normalized cutover is in pure date milliseconds; it contains no time
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// of day or timezone component, and it used to compare against other
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// pure date values.
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UDate cutoverDay = floorDivide(fGregorianCutover, kOneDay);
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fNormalizedGregorianCutover = cutoverDay * kOneDay;
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// Handle the rare case of numeric overflow. If the user specifies a
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// change of UDate(Long.MIN_VALUE), in order to get a pure Gregorian
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// calendar, then the epoch day is -106751991168, which when multiplied
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// by ONE_DAY gives 9223372036794351616 -- the negative value is too
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// large for 64 bits, and overflows into a positive value. We correct
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// this by using the next day, which for all intents is semantically
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// equivalent.
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if (cutoverDay < 0 && fNormalizedGregorianCutover > 0) {
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fNormalizedGregorianCutover = (cutoverDay + 1) * kOneDay;
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}
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// Normalize the year so BC values are represented as 0 and negative
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// values.
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GregorianCalendar *cal = new GregorianCalendar(getTimeZone(), status);
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if(U_FAILURE(status))
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return;
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cal->setTime(date, status);
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fGregorianCutoverYear = cal->get(YEAR, status);
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if (cal->get(ERA, status) == BC)
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fGregorianCutoverYear = 1 - fGregorianCutoverYear;
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delete cal;
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}
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// -------------------------------------
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UDate
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GregorianCalendar::getGregorianChange() const
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{
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return fGregorianCutover;
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}
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// -------------------------------------
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bool_t
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GregorianCalendar::isLeapYear(int32_t year) const
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{
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return (year >= fGregorianCutoverYear ?
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((year%4 == 0) && ((year%100 != 0) || (year%400 == 0))) : // Gregorian
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(year%4 == 0)); // Julian
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}
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// -------------------------------------
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/**
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* Compute the date-based fields given the milliseconds since the epoch start.
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* Do not compute the time-based fields (HOUR, MINUTE, etc.).
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*
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* @param theTime the given time as LOCAL milliseconds, not UTC.
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*/
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void
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GregorianCalendar::timeToFields(UDate theTime, bool_t quick, UErrorCode& status)
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{
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if (U_FAILURE(status))
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return;
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int32_t rawYear;
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int32_t year, month, date, dayOfWeek, dayOfYear, era;
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bool_t isLeap;
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// Compute the year, month, and day of month from the given millis
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if (theTime >= fNormalizedGregorianCutover) {
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// The Gregorian epoch day is zero for Monday January 1, year 1.
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double gregorianEpochDay = millisToJulianDay(theTime) - kJan1_1JulianDay;
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// Here we convert from the day number to the multiple radix
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// representation. We use 400-year, 100-year, and 4-year cycles.
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// For example, the 4-year cycle has 4 years + 1 leap day; giving
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// 1461 == 365*4 + 1 days.
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int32_t rem[1];
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int32_t n400 = floorDivide(gregorianEpochDay, 146097, rem); // 400-year cycle length
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int32_t n100 = floorDivide(rem[0], 36524, rem); // 100-year cycle length
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int32_t n4 = floorDivide(rem[0], 1461, rem); // 4-year cycle length
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int32_t n1 = floorDivide(rem[0], 365, rem);
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rawYear = 400*n400 + 100*n100 + 4*n4 + n1;
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dayOfYear = rem[0]; // zero-based day of year
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if (n100 == 4 || n1 == 4)
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dayOfYear = 365; // Dec 31 at end of 4- or 400-yr cycle
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else
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++rawYear;
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isLeap = ((rawYear&0x3) == 0) && // equiv. to (rawYear%4 == 0)
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(rawYear%100 != 0 || rawYear%400 == 0);
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// Gregorian day zero is a Monday
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dayOfWeek = (int32_t)icu_fmod(gregorianEpochDay + 1, 7);
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}
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else {
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// The Julian epoch day (not the same as Julian Day)
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// is zero on Saturday December 30, 0 (Gregorian).
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double julianEpochDay = millisToJulianDay(theTime) - (kJan1_1JulianDay - 2);
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rawYear = (int32_t) floorDivide(4*julianEpochDay + 1464, 1461.0);
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// Compute the Julian calendar day number for January 1, rawYear
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double january1 = 365.0 * (rawYear - 1) + floorDivide((double)(rawYear - 1), 4.0);
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dayOfYear = (int32_t)(julianEpochDay - january1); // 0-based
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// Julian leap years occurred historically every 4 years starting
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// with 8 AD. Before 8 AD the spacing is irregular; every 3 years
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// from 45 BC to 9 BC, and then none until 8 AD. However, we don't
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// implement this historical detail; instead, we implement the
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// computatinally cleaner proleptic calendar, which assumes
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// consistent 4-year cycles throughout time.
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isLeap = ((rawYear & 0x3) == 0); // equiv. to (rawYear%4 == 0)
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// Julian calendar day zero is a Saturday
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dayOfWeek = (int32_t)icu_fmod(julianEpochDay-1, 7);
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}
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// Common Julian/Gregorian calculation
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int32_t correction = 0;
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int32_t march1 = isLeap ? 60 : 59; // zero-based DOY for March 1
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if (dayOfYear >= march1)
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correction = isLeap ? 1 : 2;
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month = (12 * (dayOfYear + correction) + 6) / 367; // zero-based month
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date = dayOfYear -
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(isLeap ? kLeapNumDays[month] : kNumDays[month]) + 1; // one-based DOM
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// Normalize day of week
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dayOfWeek += (dayOfWeek < 0) ? (SUNDAY+7) : SUNDAY;
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era = AD;
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year = rawYear;
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if (year < 1) {
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era = BC;
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year = 1 - year;
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}
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internalSet(ERA, era);
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internalSet(YEAR, year);
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internalSet(MONTH, month + JANUARY); // 0-based
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internalSet(DATE, date);
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internalSet(DAY_OF_WEEK, dayOfWeek);
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internalSet(DAY_OF_YEAR, ++dayOfYear); // Convert from 0-based to 1-based
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if (quick)
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return;
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// Compute the week of the year. Valid week numbers run from 1 to 52
|
|
// or 53, depending on the year, the first day of the week, and the
|
|
// minimal days in the first week. Days at the start of the year may
|
|
// fall into the last week of the previous year; days at the end of
|
|
// the year may fall into the first week of the next year.
|
|
int32_t relDow = (dayOfWeek + 7 - getFirstDayOfWeek()) % 7; // 0..6
|
|
int32_t relDowJan1 = (dayOfWeek - dayOfYear + 701 - getFirstDayOfWeek()) % 7; // 0..6
|
|
int32_t woy = (dayOfYear - 1 + relDowJan1) / 7; // 0..53
|
|
if ((7 - relDowJan1) >= getMinimalDaysInFirstWeek()) {
|
|
++woy;
|
|
// Check to see if we are in the last week; if so, we need
|
|
// to handle the case in which we are the first week of the
|
|
// next year.
|
|
int32_t lastDoy = yearLength();
|
|
int32_t lastRelDow = (relDow + lastDoy - dayOfYear) % 7;
|
|
if (lastRelDow < 0) lastRelDow += 7;
|
|
if (dayOfYear > 359 && // Fast check which eliminates most cases
|
|
(6 - lastRelDow) >= getMinimalDaysInFirstWeek() &&
|
|
(dayOfYear + 7 - relDow) > lastDoy) woy = 1;
|
|
}
|
|
else if (woy == 0) {
|
|
// We are the last week of the previous year.
|
|
int32_t prevDoy = dayOfYear + yearLength(rawYear - 1);
|
|
woy = weekNumber(prevDoy, dayOfWeek);
|
|
}
|
|
internalSet(WEEK_OF_YEAR, woy);
|
|
|
|
internalSet(WEEK_OF_MONTH, weekNumber(date, dayOfWeek));
|
|
internalSet(DAY_OF_WEEK_IN_MONTH, (date-1) / 7 + 1);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
/**
|
|
* Return the week number of a day, within a period. This may be the week number in
|
|
* a year, or the week number in a month. Usually this will be a value >= 1, but if
|
|
* some initial days of the period are excluded from week 1, because
|
|
* minimalDaysInFirstWeek is > 1, then the week number will be zero for those
|
|
* initial days. Requires the day of week for the given date in order to determine
|
|
* the day of week of the first day of the period.
|
|
*
|
|
* @param dayOfPeriod Day-of-year or day-of-month. Should be 1 for first day of period.
|
|
* @param day Day-of-week for given dayOfPeriod. 1-based with 1=Sunday.
|
|
* @return Week number, one-based, or zero if the day falls in part of the
|
|
* month before the first week, when there are days before the first
|
|
* week because the minimum days in the first week is more than one.
|
|
*/
|
|
int32_t
|
|
GregorianCalendar::weekNumber(int32_t dayOfPeriod, int32_t dayOfWeek)
|
|
{
|
|
// Determine the day of the week of the first day of the period
|
|
// in question (either a year or a month). Zero represents the
|
|
// first day of the week on this calendar.
|
|
int32_t periodStartDayOfWeek = (dayOfWeek - getFirstDayOfWeek() - dayOfPeriod + 1) % 7;
|
|
if (periodStartDayOfWeek < 0)
|
|
periodStartDayOfWeek += 7;
|
|
|
|
// Compute the week number. Initially, ignore the first week, which
|
|
// may be fractional (or may not be). We add periodStartDayOfWeek in
|
|
// order to fill out the first week, if it is fractional.
|
|
int32_t weekNo = (dayOfPeriod + periodStartDayOfWeek - 1)/7;
|
|
|
|
// If the first week is long enough, then count it. If
|
|
// the minimal days in the first week is one, or if the period start
|
|
// is zero, we always increment weekNo.
|
|
if ((7 - periodStartDayOfWeek) >= getMinimalDaysInFirstWeek())
|
|
++weekNo;
|
|
|
|
return weekNo;
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::monthLength(int32_t month) const
|
|
{
|
|
int32_t year = internalGet(YEAR);
|
|
if(internalGetEra() == BC) {
|
|
year = 1 - year;
|
|
}
|
|
|
|
return monthLength(month, year);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::monthLength(int32_t month, int32_t year) const
|
|
{
|
|
return isLeapYear(year) ? kLeapMonthLength[month] : kMonthLength[month];
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::yearLength(int32_t year) const
|
|
{
|
|
return isLeapYear(year) ? 366 : 365;
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::yearLength() const
|
|
{
|
|
return isLeapYear(internalGet(YEAR)) ? 366 : 365;
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
/**
|
|
* Overrides Calendar
|
|
* Converts UTC as milliseconds to time field values.
|
|
* The time is <em>not</em>
|
|
* recomputed first; to recompute the time, then the fields, call the
|
|
* <code>complete</code> method.
|
|
* @see Calendar#complete
|
|
*/
|
|
void
|
|
GregorianCalendar::computeFields(UErrorCode& status)
|
|
{
|
|
if (U_FAILURE(status))
|
|
return;
|
|
|
|
int32_t rawOffset = getTimeZone().getRawOffset();
|
|
double localMillis = internalGetTime() + rawOffset;
|
|
|
|
/* Check for very extreme values -- millis near Long.MIN_VALUE or
|
|
* Long.MAX_VALUE. For these values, adding the zone offset can push
|
|
* the millis past MAX_VALUE to MIN_VALUE, or vice versa. This produces
|
|
* the undesirable effect that the time can wrap around at the ends,
|
|
* yielding, for example, a UDate(Long.MAX_VALUE) with a big BC year
|
|
* (should be AD). Handle this by pinning such values to Long.MIN_VALUE
|
|
* or Long.MAX_VALUE. - liu 8/11/98 bug 4149677 */
|
|
|
|
/* {sfb} 9/04/98
|
|
* Since in C++ we use doubles instead of longs for dates, there is
|
|
* an inherent loss of range in the calendar (because in Java you have all 64
|
|
* bits to store data, while in C++ you have only 52 bits of mantissa.
|
|
* So, I will pin to these (2^52 - 1) values instead */
|
|
|
|
if(internalGetTime() > 0 && localMillis < 0 && rawOffset > 0) {
|
|
localMillis = LATEST_SUPPORTED_MILLIS;
|
|
}
|
|
else if(internalGetTime() < 0 && localMillis > 0 && rawOffset < 0) {
|
|
localMillis = EARLIEST_SUPPORTED_MILLIS;
|
|
}
|
|
|
|
// Time to fields takes the wall millis (Standard or DST).
|
|
timeToFields(localMillis, FALSE, status);
|
|
|
|
uint8_t era = (uint8_t) internalGetEra();
|
|
int32_t year = internalGet(YEAR);
|
|
int32_t month = internalGet(MONTH);
|
|
int32_t date = internalGet(DATE);
|
|
uint8_t dayOfWeek = (uint8_t) internalGet(DAY_OF_WEEK);
|
|
|
|
double days = icu_floor(localMillis / kOneDay);
|
|
int32_t millisInDay = (int32_t) (localMillis - (days * kOneDay));
|
|
if (millisInDay < 0)
|
|
millisInDay += U_MILLIS_PER_DAY;
|
|
|
|
// Call getOffset() to get the TimeZone offset. The millisInDay value must
|
|
// be standard local millis.
|
|
int32_t dstOffset = getTimeZone().getOffset(era, year, month, date, dayOfWeek, millisInDay,
|
|
monthLength(month), status) - rawOffset;
|
|
if(U_FAILURE(status))
|
|
return;
|
|
|
|
// Adjust our millisInDay for DST, if necessary.
|
|
millisInDay += dstOffset;
|
|
|
|
// If DST has pushed us into the next day, we must call timeToFields() again.
|
|
// This happens in DST between 12:00 am and 1:00 am every day. The call to
|
|
// timeToFields() will give the wrong day, since the Standard time is in the
|
|
// previous day.
|
|
if (millisInDay >= U_MILLIS_PER_DAY) {
|
|
UDate dstMillis = localMillis + dstOffset;
|
|
millisInDay -= U_MILLIS_PER_DAY;
|
|
// As above, check for and pin extreme values
|
|
if(localMillis > 0 && dstMillis < 0 && dstOffset > 0) {
|
|
dstMillis = LATEST_SUPPORTED_MILLIS;
|
|
}
|
|
else if(localMillis < 0 && dstMillis > 0 && dstOffset < 0) {
|
|
dstMillis = EARLIEST_SUPPORTED_MILLIS;
|
|
}
|
|
timeToFields(dstMillis, FALSE, status);
|
|
}
|
|
|
|
// Fill in all time-related fields based on millisInDay. Call internalSet()
|
|
// so as not to perturb flags.
|
|
internalSet(MILLISECOND, millisInDay % 1000);
|
|
millisInDay /= 1000;
|
|
internalSet(SECOND, millisInDay % 60);
|
|
millisInDay /= 60;
|
|
internalSet(MINUTE, millisInDay % 60);
|
|
millisInDay /= 60;
|
|
internalSet(HOUR_OF_DAY, millisInDay);
|
|
internalSet(AM_PM, millisInDay / 12); // Assume AM == 0
|
|
internalSet(HOUR, millisInDay % 12);
|
|
|
|
internalSet(ZONE_OFFSET, rawOffset);
|
|
internalSet(DST_OFFSET, dstOffset);
|
|
|
|
// Careful here: We are manually setting the time stamps[] flags to
|
|
// INTERNALLY_SET, so we must be sure that the above code actually does
|
|
// set all these fields.
|
|
for (int i=0; i<FIELD_COUNT; ++i) {
|
|
fStamp[i] = kInternallySet;
|
|
fIsSet[i] = TRUE; // Remove later
|
|
}
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
/**
|
|
* After adjustments such as add(MONTH), add(YEAR), we don't want the
|
|
* month to jump around. E.g., we don't want Jan 31 + 1 month to go to Mar
|
|
* 3, we want it to go to Feb 28. Adjustments which might run into this
|
|
* problem call this method to retain the proper month.
|
|
*/
|
|
void
|
|
GregorianCalendar::pinDayOfMonth()
|
|
{
|
|
int32_t monthLen = monthLength(internalGet(MONTH));
|
|
int32_t dom = internalGet(DAY_OF_MONTH);
|
|
if(dom > monthLen)
|
|
set(DAY_OF_MONTH, monthLen);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
bool_t
|
|
GregorianCalendar::validateFields() const
|
|
{
|
|
for (int32_t field = 0; field < FIELD_COUNT; field++) {
|
|
// Ignore DATE and DAY_OF_YEAR which are handled below
|
|
if (field != DATE &&
|
|
field != DAY_OF_YEAR &&
|
|
isSet((EDateFields)field) &&
|
|
! boundsCheck(internalGet((EDateFields)field), (EDateFields)field))
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
// Values differ in Least-Maximum and Maximum should be handled
|
|
// specially.
|
|
if (isSet(DATE)) {
|
|
int32_t date = internalGet(DATE);
|
|
if (date < getMinimum(DATE) ||
|
|
date > monthLength(internalGet(MONTH))) {
|
|
return FALSE;
|
|
}
|
|
}
|
|
|
|
if (isSet(DAY_OF_YEAR)) {
|
|
int32_t days = internalGet(DAY_OF_YEAR);
|
|
if (days < 1 || days > yearLength())
|
|
return FALSE;
|
|
}
|
|
|
|
// Handle DAY_OF_WEEK_IN_MONTH, which must not have the value zero.
|
|
// We've checked against minimum and maximum above already.
|
|
if (isSet(DAY_OF_WEEK_IN_MONTH) &&
|
|
0 == internalGet(DAY_OF_WEEK_IN_MONTH))
|
|
return FALSE;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
bool_t
|
|
GregorianCalendar::boundsCheck(int32_t value, EDateFields field) const
|
|
{
|
|
return value >= getMinimum(field) && value <= getMaximum(field);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
UDate
|
|
GregorianCalendar::getEpochDay(UErrorCode& status)
|
|
{
|
|
complete(status);
|
|
// Divide by 1000 (convert to seconds) in order to prevent overflow when
|
|
// dealing with UDate(Long.MIN_VALUE) and UDate(Long.MAX_VALUE).
|
|
double wallSec = internalGetTime()/1000 + (internalGet(ZONE_OFFSET) + internalGet(DST_OFFSET))/1000;
|
|
|
|
// {sfb} force conversion to double
|
|
return icu_trunc(wallSec / (kOneDay/1000.0));
|
|
//return floorDivide(wallSec, kOneDay/1000.0);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
void
|
|
GregorianCalendar::computeTime(UErrorCode& status)
|
|
{
|
|
if (U_FAILURE(status))
|
|
return;
|
|
|
|
if (! isLenient() && ! validateFields()) {
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return;
|
|
}
|
|
|
|
// This function takes advantage of the fact that unset fields in
|
|
// the time field list have a value of zero.
|
|
|
|
// The year defaults to the epoch start.
|
|
int32_t year = (fStamp[YEAR] != kUnset) ? internalGet(YEAR) : kEpochYear;
|
|
|
|
int32_t era = AD;
|
|
if (fStamp[ERA] != kUnset) {
|
|
era = internalGet(ERA);
|
|
if (era == BC)
|
|
year = 1 - year;
|
|
// Even in lenient mode we disallow ERA values other than AD & BC
|
|
else if (era != AD) {
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return;
|
|
}
|
|
}
|
|
|
|
// First, use the year to determine whether to use the Gregorian or the
|
|
// Julian calendar. If the year is not the year of the cutover, this
|
|
// computation will be correct. But if the year is the cutover year,
|
|
// this may be incorrect. In that case, assume the Gregorian calendar,
|
|
// make the computation, and then recompute if the resultant millis
|
|
// indicate the wrong calendar has been assumed.
|
|
|
|
// A date such as Oct. 10, 1582 does not exist in a Gregorian calendar
|
|
// with the default changeover of Oct. 15, 1582, since in such a
|
|
// calendar Oct. 4 (Julian) is followed by Oct. 15 (Gregorian). This
|
|
// algorithm will interpret such a date using the Julian calendar,
|
|
// yielding Oct. 20, 1582 (Gregorian).
|
|
bool_t isGregorian = year >= fGregorianCutoverYear;
|
|
double julianDay = computeJulianDay(isGregorian, year);
|
|
double millis = julianDayToMillis(julianDay);
|
|
|
|
// The following check handles portions of the cutover year BEFORE the
|
|
// cutover itself happens. The check for the julianDate number is for a
|
|
// rare case; it's a hardcoded number, but it's efficient. The given
|
|
// Julian day number corresponds to Dec 3, 292269055 BC, which
|
|
// corresponds to millis near Long.MIN_VALUE. The need for the check
|
|
// arises because for extremely negative Julian day numbers, the millis
|
|
// actually overflow to be positive values. Without the check, the
|
|
// initial date is interpreted with the Gregorian calendar, even when
|
|
// the cutover doesn't warrant it.
|
|
if (isGregorian != (millis >= fNormalizedGregorianCutover) &&
|
|
julianDay != -106749550580.0) { // See above
|
|
julianDay = computeJulianDay(!isGregorian, year);
|
|
millis = julianDayToMillis(julianDay);
|
|
}
|
|
|
|
// Do the time portion of the conversion.
|
|
|
|
int32_t millisInDay = 0;
|
|
|
|
// Find the best set of fields specifying the time of day. There
|
|
// are only two possibilities here; the HOUR_OF_DAY or the
|
|
// AM_PM and the HOUR.
|
|
int32_t hourOfDayStamp = fStamp[HOUR_OF_DAY];
|
|
int32_t hourStamp = fStamp[HOUR];
|
|
int32_t bestStamp = (hourStamp > hourOfDayStamp) ? hourStamp : hourOfDayStamp;
|
|
|
|
// Hours
|
|
if (bestStamp != kUnset) {
|
|
if (bestStamp == hourOfDayStamp)
|
|
// Don't normalize here; let overflow bump into the next period.
|
|
// This is consistent with how we handle other fields.
|
|
millisInDay += internalGet(HOUR_OF_DAY);
|
|
|
|
else {
|
|
// Don't normalize here; let overflow bump into the next period.
|
|
// This is consistent with how we handle other fields.
|
|
millisInDay += internalGet(HOUR);
|
|
|
|
millisInDay += 12 * internalGet(AM_PM); // Default works for unset AM_PM
|
|
}
|
|
}
|
|
|
|
// We use the fact that unset == 0; we start with millisInDay
|
|
// == HOUR_OF_DAY.
|
|
millisInDay *= 60;
|
|
millisInDay += internalGet(MINUTE); // now have minutes
|
|
millisInDay *= 60;
|
|
millisInDay += internalGet(SECOND); // now have seconds
|
|
millisInDay *= 1000;
|
|
millisInDay += internalGet(MILLISECOND); // now have millis
|
|
|
|
// Compute the time zone offset and DST offset. There are two potential
|
|
// ambiguities here. We'll assume a 2:00 am (wall time) switchover time
|
|
// for discussion purposes here.
|
|
// 1. The transition into DST. Here, a designated time of 2:00 am - 2:59 am
|
|
// can be in standard or in DST depending. However, 2:00 am is an invalid
|
|
// representation (the representation jumps from 1:59:59 am Std to 3:00:00 am DST).
|
|
// We assume standard time.
|
|
// 2. The transition out of DST. Here, a designated time of 1:00 am - 1:59 am
|
|
// can be in standard or DST. Both are valid representations (the rep
|
|
// jumps from 1:59:59 DST to 1:00:00 Std).
|
|
// Again, we assume standard time.
|
|
// We use the TimeZone object, unless the user has explicitly set the ZONE_OFFSET
|
|
// or DST_OFFSET fields; then we use those fields.
|
|
const TimeZone& zone = getTimeZone();
|
|
int32_t zoneOffset = (fStamp[ZONE_OFFSET] >= kMinimumUserStamp)
|
|
/*isSet(ZONE_OFFSET) && userSetZoneOffset*/ ?
|
|
internalGet(ZONE_OFFSET) : zone.getRawOffset();
|
|
|
|
// Now add date and millisInDay together, to make millis contain local wall
|
|
// millis, with no zone or DST adjustments
|
|
millis += millisInDay;
|
|
|
|
int32_t dstOffset = 0;
|
|
if (fStamp[ZONE_OFFSET] >= kMinimumUserStamp
|
|
/*isSet(DST_OFFSET) && userSetDSTOffset*/)
|
|
dstOffset = internalGet(DST_OFFSET);
|
|
else {
|
|
/* Normalize the millisInDay to 0..ONE_DAY-1. If the millis is out
|
|
* of range, then we must call timeToFields() to recompute our
|
|
* fields. */
|
|
int32_t normalizedMillisInDay [1];
|
|
floorDivide(millis, (int32_t)kOneDay, normalizedMillisInDay);
|
|
|
|
// We need to have the month, the day, and the day of the week.
|
|
// Calling timeToFields will compute the MONTH and DATE fields.
|
|
// If we're lenient then we need to call timeToFields() to
|
|
// normalize the year, month, and date numbers.
|
|
uint8_t dow;
|
|
if (isLenient() || fStamp[MONTH] == kUnset || fStamp[DATE] == kUnset
|
|
|| millisInDay != normalizedMillisInDay[0]) {
|
|
timeToFields(millis, TRUE, status); // Use wall time; true == do quick computation
|
|
dow = (uint8_t) internalGet(DAY_OF_WEEK); // DOW is computed by timeToFields
|
|
}
|
|
else {
|
|
// It's tempting to try to use DAY_OF_WEEK here, if it
|
|
// is set, but we CAN'T. Even if it's set, it might have
|
|
// been set wrong by the user. We should rely only on
|
|
// the Julian day number, which has been computed correctly
|
|
// using the disambiguation algorithm above. [LIU]
|
|
dow = julianDayToDayOfWeek(julianDay);
|
|
}
|
|
|
|
// It's tempting to try to use DAY_OF_WEEK here, if it
|
|
// is set, but we CAN'T. Even if it's set, it might have
|
|
// been set wrong by the user. We should rely only on
|
|
// the Julian day number, which has been computed correctly
|
|
// using the disambiguation algorithm above. [LIU]
|
|
dstOffset = zone.getOffset((uint8_t)era,
|
|
internalGet(YEAR),
|
|
internalGet(MONTH),
|
|
internalGet(DATE),
|
|
dow,
|
|
normalizedMillisInDay[0],
|
|
monthLength(internalGet(MONTH)),
|
|
status) -
|
|
zoneOffset;
|
|
// Note: Because we pass in wall millisInDay, rather than
|
|
// standard millisInDay, we interpret "1:00 am" on the day
|
|
// of cessation of DST as "1:00 am Std" (assuming the time
|
|
// of cessation is 2:00 am).
|
|
}
|
|
|
|
// Store our final computed GMT time, with timezone adjustments.
|
|
internalSetTime(millis - zoneOffset - dstOffset);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
double
|
|
GregorianCalendar::computeJulianDay(bool_t isGregorian, int32_t year)
|
|
{
|
|
int32_t month = 0;
|
|
int32_t date = 0;
|
|
int32_t y;
|
|
double millis = 0;
|
|
|
|
// Find the most recent set of fields specifying the day within
|
|
// the year. These may be any of the following combinations:
|
|
// MONTH* + DAY_OF_MONTH*
|
|
// MONTH* + WEEK_OF_MONTH* + DAY_OF_WEEK
|
|
// MONTH* + DAY_OF_WEEK_IN_MONTH* + DAY_OF_WEEK
|
|
// DAY_OF_YEAR*
|
|
// WEEK_OF_YEAR* + DAY_OF_WEEK
|
|
// We look for the most recent of the fields marked thus*. If other
|
|
// fields are missing, we use their default values, which are those of
|
|
// the epoch start, or in the case of DAY_OF_WEEK, the first day in
|
|
// the week.
|
|
int32_t monthStamp = fStamp[MONTH];
|
|
int32_t domStamp = fStamp[DAY_OF_MONTH];
|
|
int32_t womStamp = fStamp[WEEK_OF_MONTH];
|
|
int32_t dowimStamp = fStamp[DAY_OF_WEEK_IN_MONTH];
|
|
int32_t doyStamp = fStamp[DAY_OF_YEAR];
|
|
int32_t woyStamp = fStamp[WEEK_OF_YEAR];
|
|
|
|
int32_t bestStamp = (monthStamp > domStamp) ? monthStamp : domStamp;
|
|
if (womStamp > bestStamp) bestStamp = womStamp;
|
|
if (dowimStamp > bestStamp) bestStamp = dowimStamp;
|
|
if (doyStamp > bestStamp) bestStamp = doyStamp;
|
|
if (woyStamp > bestStamp) bestStamp = woyStamp;
|
|
|
|
bool_t useMonth = FALSE;
|
|
|
|
if (bestStamp != kUnset &&
|
|
(bestStamp == monthStamp ||
|
|
bestStamp == domStamp ||
|
|
bestStamp == womStamp ||
|
|
bestStamp == dowimStamp)) {
|
|
useMonth = TRUE;
|
|
|
|
// We have the month specified. Make it 0-based for the algorithm.
|
|
month = (monthStamp != kUnset) ? internalGet(MONTH) - JANUARY : 0;
|
|
|
|
// If the month is out of range, adjust it into range
|
|
if (month < 0 || month > 11) {
|
|
int32_t rem[1];
|
|
year += floorDivide(month, 12, rem);
|
|
month = rem[0];
|
|
}
|
|
}
|
|
|
|
bool_t isLeap = year%4 == 0;
|
|
y = year - 1;
|
|
double julianDay = 365.0*y + floorDivide(y, 4) + (kJan1_1JulianDay - 3);
|
|
|
|
if (isGregorian) {
|
|
isLeap = isLeap && ((year%100 != 0) || (year%400 == 0));
|
|
// Add 2 because Gregorian calendar starts 2 days after Julian calendar
|
|
julianDay += floorDivide(y, 400) - floorDivide(y, 100) + 2;
|
|
}
|
|
|
|
// At this point julianDay is the 0-based day BEFORE the first day of
|
|
// January 1, year 1 of the given calendar. If julianDay == 0, it
|
|
// specifies (Jan. 1, 1) - 1, in whatever calendar we are using (Julian
|
|
// or Gregorian).
|
|
|
|
if (useMonth) {
|
|
|
|
julianDay += isLeap ? kLeapNumDays[month] : kNumDays[month];
|
|
|
|
if (bestStamp == domStamp ||
|
|
bestStamp == monthStamp) {
|
|
|
|
date = (domStamp != kUnset) ? internalGet(DAY_OF_MONTH) : 1;
|
|
}
|
|
else { // assert(bestStamp == womStamp || bestStamp == dowimStamp)
|
|
// Compute from day of week plus week number or from the day of
|
|
// week plus the day of week in month. The computations are
|
|
// almost identical.
|
|
|
|
// Find the day of the week for the first of this month. This
|
|
// is zero-based, with 0 being the locale-specific first day of
|
|
// the week. Add 1 to get the 1st day of month. Subtract
|
|
// getFirstDayOfWeek() to make 0-based.
|
|
int32_t fdm = julianDayToDayOfWeek(julianDay + 1) - getFirstDayOfWeek();
|
|
if (fdm < 0)
|
|
fdm += 7;
|
|
|
|
// Find the start of the first week. This will be a date from
|
|
// 1..-6. It represents the locale-specific first day of the
|
|
// week of the first day of the month, ignoring minimal days in
|
|
// first week.
|
|
date = 1 - fdm + ((fStamp[DAY_OF_WEEK] != kUnset) ?
|
|
(internalGet(DAY_OF_WEEK) - getFirstDayOfWeek()) : 0);
|
|
|
|
if (bestStamp == womStamp) {
|
|
// Adjust for minimal days in first week.
|
|
if ((7 - fdm) < getMinimalDaysInFirstWeek())
|
|
date += 7;
|
|
|
|
// Now adjust for the week number.
|
|
date += 7 * (internalGet(WEEK_OF_MONTH) - 1);
|
|
}
|
|
else { // assert(bestStamp == dowimStamp)
|
|
// Adjust into the month, if needed.
|
|
if (date < 1) date += 7;
|
|
|
|
// We are basing this on the day-of-week-in-month. The only
|
|
// trickiness occurs if the day-of-week-in-month is
|
|
// negative.
|
|
int32_t dim = internalGet(DAY_OF_WEEK_IN_MONTH);
|
|
if (dim >= 0)
|
|
date += 7*(dim - 1);
|
|
else {
|
|
// Move date to the last of this day-of-week in this
|
|
// month, then back up as needed. If dim==-1, we don't
|
|
// back up at all. If dim==-2, we back up once, etc.
|
|
// Don't back up past the first of the given day-of-week
|
|
// in this month. Note that we handle -2, -3,
|
|
// etc. correctly, even though values < -1 are
|
|
// technically disallowed.
|
|
date += ((monthLength(internalGet(MONTH), year) - date) / 7 + dim + 1) * 7;
|
|
}
|
|
}
|
|
}
|
|
|
|
julianDay += date;
|
|
}
|
|
else {
|
|
// assert(bestStamp == doyStamp || bestStamp == woyStamp ||
|
|
// bestStamp == UNSET). In the last case we should use January 1.
|
|
|
|
// No month, start with January 0 (day before Jan 1), then adjust.
|
|
|
|
if (bestStamp == kUnset) {
|
|
++julianDay; // Advance to January 1
|
|
}
|
|
else if (bestStamp == doyStamp) {
|
|
julianDay += internalGet(DAY_OF_YEAR);
|
|
}
|
|
else if (bestStamp == woyStamp) {
|
|
// Compute from day of week plus week of year
|
|
|
|
// Find the day of the week for the first of this year. This
|
|
// is zero-based, with 0 being the locale-specific first day of
|
|
// the week. Add 1 to get the 1st day of month. Subtract
|
|
// getFirstDayOfWeek() to make 0-based.
|
|
int32_t fdy = julianDayToDayOfWeek(julianDay + 1) - getFirstDayOfWeek();
|
|
if (fdy < 0)
|
|
fdy += 7;
|
|
|
|
// Find the start of the first week. This may be a valid date
|
|
// from 1..7, or a date before the first, from 0..-6. It
|
|
// represents the locale-specific first day of the week
|
|
// of the first day of the year.
|
|
|
|
// First ignore the minimal days in first week.
|
|
date = 1 - fdy + ((fStamp[DAY_OF_WEEK] != kUnset) ?
|
|
(internalGet(DAY_OF_WEEK) - getFirstDayOfWeek()) : 0);
|
|
|
|
// Adjust for minimal days in first week.
|
|
if ((7 - fdy) < getMinimalDaysInFirstWeek())
|
|
date += 7;
|
|
|
|
// Now adjust for the week number.
|
|
date += 7 * (internalGet(WEEK_OF_YEAR) - 1);
|
|
|
|
julianDay += date;
|
|
}
|
|
}
|
|
|
|
return julianDay;
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
double
|
|
GregorianCalendar::millisToJulianDay(UDate millis)
|
|
{
|
|
return (double)kEpochStartAsJulianDay + floorDivide(millis, kOneDay);
|
|
//return kEpochStartAsJulianDay + icu_trunc(millis / kOneDay);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
UDate
|
|
GregorianCalendar::julianDayToMillis(double julian)
|
|
{
|
|
return (UDate) ((julian - kEpochStartAsJulianDay) * (double) kOneDay);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
double
|
|
GregorianCalendar::floorDivide(double numerator, double denominator)
|
|
{
|
|
return icu_floor(numerator / denominator);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::floorDivide(int32_t numerator, int32_t denominator)
|
|
{
|
|
// We do this computation in order to handle
|
|
// a numerator of Long.MIN_VALUE correctly
|
|
return (numerator >= 0) ?
|
|
numerator / denominator :
|
|
((numerator + 1) / denominator) - 1;
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::floorDivide(int32_t numerator, int32_t denominator, int32_t remainder[])
|
|
{
|
|
if (numerator >= 0) {
|
|
remainder[0] = numerator % denominator;
|
|
return numerator / denominator;
|
|
}
|
|
int32_t quotient = ((numerator + 1) / denominator) - 1;
|
|
remainder[0] = numerator - (quotient * denominator);
|
|
return quotient;
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::floorDivide(double numerator, int32_t denominator, int32_t remainder[])
|
|
{
|
|
if (numerator >= 0) {
|
|
remainder[0] = (int32_t)icu_fmod(numerator, denominator);
|
|
return (int32_t)icu_trunc(numerator / denominator);
|
|
}
|
|
int32_t quotient = (int32_t)(icu_trunc((numerator + 1) / denominator) - 1);
|
|
remainder[0] = (int32_t)(numerator - ((double)quotient * denominator));
|
|
return quotient;
|
|
}
|
|
|
|
|
|
// -------------------------------------
|
|
|
|
// {sfb} why does this work, while Calendar::EStampValues doesn't?
|
|
GregorianCalendar::EStampValues
|
|
GregorianCalendar::aggregateStamp(EStampValues stamp_a, EStampValues stamp_b)
|
|
{
|
|
return ((EStampValues)((stamp_a != kUnset && stamp_b != kUnset)
|
|
? icu_max((int32_t)stamp_a, (int32_t)stamp_b)
|
|
: kUnset));
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
void
|
|
GregorianCalendar::add(EDateFields field, int32_t amount, UErrorCode& status)
|
|
{
|
|
if (U_FAILURE(status))
|
|
return;
|
|
|
|
if (amount == 0)
|
|
return; // Do nothing!
|
|
complete(status);
|
|
|
|
if (field == YEAR) {
|
|
int32_t year = internalGet(YEAR);
|
|
if (internalGetEra() == AD) {
|
|
year += amount;
|
|
if (year > 0)
|
|
set(YEAR, year);
|
|
else { // year <= 0
|
|
set(YEAR, 1 - year);
|
|
// if year == 0, you get 1 BC
|
|
set(ERA, BC);
|
|
}
|
|
}
|
|
else { // era == BC
|
|
year -= amount;
|
|
if (year > 0)
|
|
set(YEAR, year);
|
|
else { // year <= 0
|
|
set(YEAR, 1 - year);
|
|
// if year == 0, you get 1 AD
|
|
set(ERA, AD);
|
|
}
|
|
}
|
|
pinDayOfMonth();
|
|
}
|
|
else if (field == MONTH) {
|
|
int32_t month = internalGet(MONTH) + amount;
|
|
if (month >= 0) {
|
|
add(YEAR, (int32_t) (month / 12), status);
|
|
set(MONTH, (int32_t) (month % 12));
|
|
}
|
|
else { // month < 0
|
|
|
|
add(YEAR, (int32_t) ((month + 1) / 12) - 1, status);
|
|
month %= 12;
|
|
if (month < 0)
|
|
month += 12;
|
|
set(MONTH, JANUARY + month);
|
|
}
|
|
pinDayOfMonth();
|
|
}
|
|
else if (field == ERA) {
|
|
int32_t era = internalGet(ERA) + amount;
|
|
if (era < 0)
|
|
era = 0;
|
|
if (era > 1)
|
|
era = 1;
|
|
set(ERA, era);
|
|
}
|
|
else {
|
|
// We handle most fields here. The algorithm is to add a computed amount
|
|
// of millis to the current millis. The only wrinkle is with DST -- if
|
|
// the result of the add operation is to move from DST to Standard, or vice
|
|
// versa, we need to adjust by an hour forward or back, respectively.
|
|
// Otherwise you get weird effects in which the hour seems to shift when
|
|
// you add to the DAY_OF_MONTH field, for instance.
|
|
|
|
// We only adjust the DST for fields larger than an hour. For fields
|
|
// smaller than an hour, we cannot adjust for DST without causing problems.
|
|
// for instance, if you add one hour to April 5, 1998, 1:00 AM, in PST,
|
|
// the time becomes "2:00 AM PDT" (an illegal value), but then the adjustment
|
|
// sees the change and compensates by subtracting an hour. As a result the
|
|
// time doesn't advance at all.
|
|
|
|
// {sfb} do we want to use a double here, or a int32_t?
|
|
// probably a double, since if we used a int32_t in the
|
|
// WEEK_OF_YEAR clause below, if delta was greater than approx.
|
|
// 7.1 we would reach the limit of a int32_t
|
|
double delta = amount;
|
|
bool_t adjustDST = TRUE;
|
|
|
|
switch (field) {
|
|
case WEEK_OF_YEAR:
|
|
case WEEK_OF_MONTH:
|
|
case DAY_OF_WEEK_IN_MONTH:
|
|
delta *= 7 * 24 * 60 * 60 * 1000; // 7 days
|
|
break;
|
|
|
|
case AM_PM:
|
|
delta *= 12 * 60 * 60 * 1000; // 12 hrs
|
|
break;
|
|
|
|
case DATE: // synonym of DAY_OF_MONTH
|
|
case DAY_OF_YEAR:
|
|
case DAY_OF_WEEK:
|
|
delta *= 24 * 60 * 60 * 1000; // 1 day
|
|
break;
|
|
|
|
case HOUR_OF_DAY:
|
|
case HOUR:
|
|
delta *= 60 * 60 * 1000; // 1 hour
|
|
adjustDST = FALSE;
|
|
break;
|
|
|
|
case MINUTE:
|
|
delta *= 60 * 1000; // 1 minute
|
|
adjustDST = FALSE;
|
|
break;
|
|
|
|
case SECOND:
|
|
delta *= 1000; // 1 second
|
|
adjustDST = FALSE;
|
|
break;
|
|
|
|
case MILLISECOND:
|
|
adjustDST = FALSE;
|
|
break;
|
|
|
|
case ZONE_OFFSET:
|
|
case DST_OFFSET:
|
|
default:
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return;
|
|
}
|
|
|
|
// Save the current DST state.
|
|
int32_t dst = 0;
|
|
if (adjustDST)
|
|
dst = internalGet(DST_OFFSET);
|
|
|
|
setTimeInMillis(internalGetTime() + delta, status); // Automatically computes fields if necessary
|
|
|
|
if (adjustDST) {
|
|
// Now do the DST adjustment alluded to above.
|
|
// Only call setTimeInMillis if necessary, because it's an expensive call.
|
|
dst -= internalGet(DST_OFFSET);
|
|
if(dst!= 0)
|
|
setTimeInMillis(internalGetTime() + dst, status);
|
|
}
|
|
}
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
/**
|
|
* Roll a field by a signed amount.
|
|
* Note: This will be made public later. [LIU]
|
|
*/
|
|
void
|
|
GregorianCalendar::roll(EDateFields field, int32_t amount, UErrorCode& status)
|
|
{
|
|
if(U_FAILURE(status))
|
|
return;
|
|
|
|
if (amount == 0)
|
|
return; // Nothing to do
|
|
|
|
int32_t min = 0, max = 0, gap;
|
|
if (field >= 0 && field < FIELD_COUNT) {
|
|
complete(status);
|
|
min = getMinimum(field);
|
|
max = getMaximum(field);
|
|
}
|
|
|
|
switch (field) {
|
|
case ERA:
|
|
case YEAR:
|
|
case AM_PM:
|
|
case MINUTE:
|
|
case SECOND:
|
|
case MILLISECOND:
|
|
// These fields are handled simply, since they have fixed minima
|
|
// and maxima. The field DAY_OF_MONTH is almost as simple. Other
|
|
// fields are complicated, since the range within they must roll
|
|
// varies depending on the date.
|
|
break;
|
|
|
|
case HOUR:
|
|
case HOUR_OF_DAY:
|
|
// Rolling the hour is difficult on the ONSET and CEASE days of
|
|
// daylight savings. For example, if the change occurs at
|
|
// 2 AM, we have the following progression:
|
|
// ONSET: 12 Std -> 1 Std -> 3 Dst -> 4 Dst
|
|
// CEASE: 12 Dst -> 1 Dst -> 1 Std -> 2 Std
|
|
// To get around this problem we don't use fields; we manipulate
|
|
// the time in millis directly.
|
|
{
|
|
// Assume min == 0 in calculations below
|
|
UDate start = getTime(status);
|
|
int32_t oldHour = internalGet(field);
|
|
int32_t newHour = (oldHour + amount) % (max + 1);
|
|
if(newHour < 0)
|
|
newHour += max + 1;
|
|
setTime(start + ((double)kOneHour * (newHour - oldHour)), status);
|
|
return;
|
|
}
|
|
case MONTH:
|
|
// Rolling the month involves both pinning the final value to [0, 11]
|
|
// and adjusting the DAY_OF_MONTH if necessary. We only adjust the
|
|
// DAY_OF_MONTH if, after updating the MONTH field, it is illegal.
|
|
// E.g., <jan31>.roll(MONTH, 1) -> <feb28> or <feb29>.
|
|
{
|
|
int32_t mon = (internalGet(MONTH) + amount) % 12;
|
|
if (mon < 0)
|
|
mon += 12;
|
|
set(MONTH, mon);
|
|
|
|
// Keep the day of month in range. We don't want to spill over
|
|
// into the next month; e.g., we don't want jan31 + 1 mo -> feb31 ->
|
|
// mar3.
|
|
// NOTE: We could optimize this later by checking for dom <= 28
|
|
// first. Do this if there appears to be a need. [LIU]
|
|
int32_t monthLen = monthLength(mon);
|
|
int32_t dom = internalGet(DAY_OF_MONTH);
|
|
if (dom > monthLen)
|
|
set(DAY_OF_MONTH, monthLen);
|
|
return;
|
|
}
|
|
|
|
case WEEK_OF_YEAR:
|
|
{
|
|
// Unlike WEEK_OF_MONTH, WEEK_OF_YEAR never shifts the day of the
|
|
// week. Also, rolling the week of the year can have seemingly
|
|
// strange effects simply because the year of the week of year
|
|
// may be different from the calendar year. For example, the
|
|
// date Dec 28, 1997 is the first day of week 1 of 1998 (if
|
|
// weeks start on Sunday and the minimal days in first week is
|
|
// <= 3).
|
|
int32_t woy = internalGet(WEEK_OF_YEAR);
|
|
// Get the ISO year, which matches the week of year. This
|
|
// may be one year before or after the calendar year.
|
|
int32_t isoYear = internalGet(YEAR);
|
|
int32_t isoDoy = internalGet(DAY_OF_YEAR);
|
|
if (internalGet(MONTH) == Calendar::JANUARY) {
|
|
if (woy >= 52) {
|
|
--isoYear;
|
|
isoDoy += yearLength(isoYear);
|
|
}
|
|
}
|
|
else {
|
|
if (woy == 1) {
|
|
isoDoy -= yearLength(isoYear);
|
|
++isoYear;
|
|
}
|
|
}
|
|
woy += amount;
|
|
// Do fast checks to avoid unnecessary computation:
|
|
if (woy < 1 || woy > 52) {
|
|
// Determine the last week of the ISO year.
|
|
// We do this using the standard formula we use
|
|
// everywhere in this file. If we can see that the
|
|
// days at the end of the year are going to fall into
|
|
// week 1 of the next year, we drop the last week by
|
|
// subtracting 7 from the last day of the year.
|
|
int32_t lastDoy = yearLength(isoYear);
|
|
int32_t lastRelDow = (lastDoy - isoDoy + internalGet(DAY_OF_WEEK) -
|
|
getFirstDayOfWeek()) % 7;
|
|
if (lastRelDow < 0)
|
|
lastRelDow += 7;
|
|
if ((6 - lastRelDow) >= getMinimalDaysInFirstWeek())
|
|
lastDoy -= 7;
|
|
int32_t lastWoy = weekNumber(lastDoy, lastRelDow + 1);
|
|
woy = ((woy + lastWoy - 1) % lastWoy) + 1;
|
|
}
|
|
set(WEEK_OF_YEAR, woy);
|
|
set(YEAR, isoYear);
|
|
return;
|
|
}
|
|
case WEEK_OF_MONTH:
|
|
{
|
|
// This is tricky, because during the roll we may have to shift
|
|
// to a different day of the week. For example:
|
|
|
|
// s m t w r f s
|
|
// 1 2 3 4 5
|
|
// 6 7 8 9 10 11 12
|
|
|
|
// When rolling from the 6th or 7th back one week, we go to the
|
|
// 1st (assuming that the first partial week counts). The same
|
|
// thing happens at the end of the month.
|
|
|
|
// The other tricky thing is that we have to figure out whether
|
|
// the first partial week actually counts or not, based on the
|
|
// minimal first days in the week. And we have to use the
|
|
// correct first day of the week to delineate the week
|
|
// boundaries.
|
|
|
|
// Here's our algorithm. First, we find the real boundaries of
|
|
// the month. Then we discard the first partial week if it
|
|
// doesn't count in this locale. Then we fill in the ends with
|
|
// phantom days, so that the first partial week and the last
|
|
// partial week are full weeks. We then have a nice square
|
|
// block of weeks. We do the usual rolling within this block,
|
|
// as is done elsewhere in this method. If we wind up on one of
|
|
// the phantom days that we added, we recognize this and pin to
|
|
// the first or the last day of the month. Easy, eh?
|
|
|
|
// Normalize the DAY_OF_WEEK so that 0 is the first day of the week
|
|
// in this locale. We have dow in 0..6.
|
|
int32_t dow = internalGet(DAY_OF_WEEK) - getFirstDayOfWeek();
|
|
if (dow < 0)
|
|
dow += 7;
|
|
|
|
// Find the day of the week (normalized for locale) for the first
|
|
// of the month.
|
|
int32_t fdm = (dow - internalGet(DAY_OF_MONTH) + 1) % 7;
|
|
if (fdm < 0)
|
|
fdm += 7;
|
|
|
|
// Get the first day of the first full week of the month,
|
|
// including phantom days, if any. Figure out if the first week
|
|
// counts or not; if it counts, then fill in phantom days. If
|
|
// not, advance to the first real full week (skip the partial week).
|
|
int32_t start;
|
|
if ((7 - fdm) < getMinimalDaysInFirstWeek())
|
|
start = 8 - fdm; // Skip the first partial week
|
|
else
|
|
start = 1 - fdm; // This may be zero or negative
|
|
|
|
// Get the day of the week (normalized for locale) for the last
|
|
// day of the month.
|
|
int32_t monthLen = monthLength(internalGet(MONTH));
|
|
int32_t ldm = (monthLen - internalGet(DAY_OF_MONTH) + dow) % 7;
|
|
// We know monthLen >= DAY_OF_MONTH so we skip the += 7 step here.
|
|
|
|
// Get the limit day for the blocked-off rectangular month; that
|
|
// is, the day which is one past the last day of the month,
|
|
// after the month has already been filled in with phantom days
|
|
// to fill out the last week. This day has a normalized DOW of 0.
|
|
int32_t limit = monthLen + 7 - ldm;
|
|
|
|
// Now roll between start and (limit - 1).
|
|
gap = limit - start;
|
|
int32_t day_of_month = (internalGet(DAY_OF_MONTH) + amount*7 -
|
|
start) % gap;
|
|
if (day_of_month < 0)
|
|
day_of_month += gap;
|
|
day_of_month += start;
|
|
|
|
// Finally, pin to the real start and end of the month.
|
|
if (day_of_month < 1)
|
|
day_of_month = 1;
|
|
if (day_of_month > monthLen)
|
|
day_of_month = monthLen;
|
|
|
|
// Set the DAY_OF_MONTH. We rely on the fact that this field
|
|
// takes precedence over everything else (since all other fields
|
|
// are also set at this point). If this fact changes (if the
|
|
// disambiguation algorithm changes) then we will have to unset
|
|
// the appropriate fields here so that DAY_OF_MONTH is attended
|
|
// to.
|
|
set(DAY_OF_MONTH, day_of_month);
|
|
return;
|
|
}
|
|
case DAY_OF_MONTH:
|
|
max = monthLength(internalGet(MONTH));
|
|
break;
|
|
case DAY_OF_YEAR:
|
|
{
|
|
// Roll the day of year using millis. Compute the millis for
|
|
// the start of the year, and get the length of the year.
|
|
double delta = amount * kOneDay; // Scale up from days to millis
|
|
double min2 = internalGetTime() - (internalGet(DAY_OF_YEAR) - 1) * kOneDay;
|
|
int32_t yearLen = yearLength();
|
|
internalSetTime( icu_fmod((internalGetTime() + delta - min2), (yearLen * kOneDay)));
|
|
if (internalGetTime() < 0)
|
|
internalSetTime( internalGetTime() + yearLen * kOneDay);
|
|
|
|
setTimeInMillis(internalGetTime() + min2, status);
|
|
return;
|
|
}
|
|
case DAY_OF_WEEK:
|
|
{
|
|
// Roll the day of week using millis. Compute the millis for
|
|
// the start of the week, using the first day of week setting.
|
|
// Restrict the millis to [start, start+7days).
|
|
double delta = amount * kOneDay; // Scale up from days to millis
|
|
// Compute the number of days before the current day in this
|
|
// week. This will be a value 0..6.
|
|
int32_t leadDays = internalGet(DAY_OF_WEEK) - getFirstDayOfWeek();
|
|
if (leadDays < 0)
|
|
leadDays += 7;
|
|
double min2 = internalGetTime() - leadDays * kOneDay;
|
|
internalSetTime(icu_fmod((internalGetTime() + delta - min2), kOneWeek));
|
|
if (internalGetTime() < 0)
|
|
internalSetTime(internalGetTime() + kOneWeek);
|
|
setTimeInMillis(internalGetTime() + min2, status);
|
|
return;
|
|
}
|
|
case DAY_OF_WEEK_IN_MONTH:
|
|
{
|
|
// Roll the day of week in the month using millis. Determine
|
|
// the first day of the week in the month, and then the last,
|
|
// and then roll within that range.
|
|
double delta = amount * kOneWeek; // Scale up from weeks to millis
|
|
// Find the number of same days of the week before this one
|
|
// in this month.
|
|
int32_t preWeeks = (internalGet(DAY_OF_MONTH) - 1) / 7;
|
|
// Find the number of same days of the week after this one
|
|
// in this month.
|
|
int32_t postWeeks = (monthLength(internalGet(MONTH)) - internalGet(DAY_OF_MONTH)) / 7;
|
|
// From these compute the min and gap millis for rolling.
|
|
double min2 = internalGetTime() - preWeeks * kOneWeek;
|
|
double gap2 = kOneWeek * (preWeeks + postWeeks + 1); // Must add 1!
|
|
// Roll within this range
|
|
internalSetTime(icu_fmod((internalGetTime() + delta - min2), gap2));
|
|
if (internalGetTime() < 0)
|
|
internalSetTime(internalGetTime() + gap2);
|
|
setTimeInMillis(internalGetTime() + min2, status);
|
|
return;
|
|
}
|
|
case ZONE_OFFSET:
|
|
case DST_OFFSET:
|
|
default:
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return;
|
|
// These fields cannot be rolled
|
|
}
|
|
|
|
// These are the standard roll instructions. These work for all
|
|
// simple cases, that is, cases in which the limits are fixed, such
|
|
// as the hour, the month, and the era.
|
|
gap = max - min + 1;
|
|
int32_t value = internalGet(field) + amount;
|
|
value = (value - min) % gap;
|
|
if (value < 0)
|
|
value += gap;
|
|
value += min;
|
|
|
|
set(field, value);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::getMinimum(EDateFields field) const
|
|
{
|
|
return kMinValues[field];
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::getMaximum(EDateFields field) const
|
|
{
|
|
return kMaxValues[field];
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::getGreatestMinimum(EDateFields field) const
|
|
{
|
|
return kMinValues[field];
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::getLeastMaximum(EDateFields field) const
|
|
{
|
|
return kLeastMaxValues[field];
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::getActualMinimum(EDateFields field) const
|
|
{
|
|
return getMinimum(field);
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::getActualMaximum(EDateFields field) const
|
|
{
|
|
/* It is a known limitation that the code here (and in getActualMinimum)
|
|
* won't behave properly at the extreme limits of GregorianCalendar's
|
|
* representable range (except for the code that handles the YEAR
|
|
* field). That's because the ends of the representable range are at
|
|
* odd spots in the year. For calendars with the default Gregorian
|
|
* cutover, these limits are Sun Dec 02 16:47:04 GMT 292269055 BC to Sun
|
|
* Aug 17 07:12:55 GMT 292278994 AD, somewhat different for non-GMT
|
|
* zones. As a result, if the calendar is set to Aug 1 292278994 AD,
|
|
* the actual maximum of DAY_OF_MONTH is 17, not 30. If the date is Mar
|
|
* 31 in that year, the actual maximum month might be Jul, whereas is
|
|
* the date is Mar 15, the actual maximum might be Aug -- depending on
|
|
* the precise semantics that are desired. Similar considerations
|
|
* affect all fields. Nonetheless, this effect is sufficiently arcane
|
|
* that we permit it, rather than complicating the code to handle such
|
|
* intricacies. - liu 8/20/98 */
|
|
|
|
UErrorCode status = U_ZERO_ERROR;
|
|
|
|
switch (field) {
|
|
// we have functions that enable us to fast-path number of days in month
|
|
// of year
|
|
case DAY_OF_MONTH:
|
|
return monthLength(get(MONTH, status));
|
|
|
|
case DAY_OF_YEAR:
|
|
return yearLength();
|
|
|
|
// for week of year, week of month, or day of week in month, we
|
|
// just fall back on the default implementation in Calendar (I'm not sure
|
|
// we could do better by having special calculations here)
|
|
case WEEK_OF_YEAR:
|
|
case WEEK_OF_MONTH:
|
|
case DAY_OF_WEEK_IN_MONTH:
|
|
return Calendar::getActualMaximum(field, status);
|
|
|
|
case YEAR:
|
|
/* The year computation is no different, in principle, from the
|
|
* others, however, the range of possible maxima is large. In
|
|
* addition, the way we know we've exceeded the range is different.
|
|
* For these reasons, we use the special case code below to handle
|
|
* this field.
|
|
*
|
|
* The actual maxima for YEAR depend on the type of calendar:
|
|
*
|
|
* Gregorian = May 17, 292275056 BC - Aug 17, 292278994 AD
|
|
* Julian = Dec 2, 292269055 BC - Jan 3, 292272993 AD
|
|
* Hybrid = Dec 2, 292269055 BC - Aug 17, 292278994 AD
|
|
*
|
|
* We know we've exceeded the maximum when either the month, date,
|
|
* time, or era changes in response to setting the year. We don't
|
|
* check for month, date, and time here because the year and era are
|
|
* sufficient to detect an invalid year setting. NOTE: If code is
|
|
* added to check the month and date in the future for some reason,
|
|
* Feb 29 must be allowed to shift to Mar 1 when setting the year.
|
|
*/
|
|
{
|
|
Calendar *cal = (Calendar*)this->clone();
|
|
cal->setLenient(TRUE);
|
|
|
|
int32_t era = cal->get(ERA, status);
|
|
if(U_FAILURE(status))
|
|
return 0;
|
|
|
|
UDate d = cal->getTime(status);
|
|
if(U_FAILURE(status))
|
|
return 0;
|
|
|
|
/* Perform a binary search, with the invariant that lowGood is a
|
|
* valid year, and highBad is an out of range year.
|
|
*/
|
|
int32_t lowGood = kLeastMaxValues[YEAR];
|
|
int32_t highBad = kMaxValues[YEAR] + 1;
|
|
while((lowGood + 1) < highBad) {
|
|
int32_t y = (lowGood + highBad) / 2;
|
|
cal->set(YEAR, y);
|
|
if(cal->get(YEAR, status) == y && cal->get(ERA, status) == era) {
|
|
lowGood = y;
|
|
}
|
|
else {
|
|
highBad = y;
|
|
cal->setTime(d, status); // Restore original fields
|
|
}
|
|
}
|
|
|
|
delete cal;
|
|
return lowGood;
|
|
}
|
|
|
|
// and we know none of the other fields have variable maxima in
|
|
// GregorianCalendar, so we can just return the fixed maximum
|
|
default:
|
|
return getMaximum(field);
|
|
}
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
bool_t
|
|
GregorianCalendar::inDaylightTime(UErrorCode& status) const
|
|
{
|
|
if (U_FAILURE(status) || !getTimeZone().useDaylightTime())
|
|
return FALSE;
|
|
|
|
// Force an update of the state of the Calendar.
|
|
((GregorianCalendar*)this)->complete(status); // cast away const
|
|
|
|
return U_SUCCESS(status) ? (internalGet(DST_OFFSET) != 0) : FALSE;
|
|
}
|
|
|
|
// -------------------------------------
|
|
|
|
int32_t
|
|
GregorianCalendar::getISOYear(UErrorCode& status)
|
|
{
|
|
((GregorianCalendar*)this)->complete(status);
|
|
|
|
int32_t woy = internalGet(WEEK_OF_YEAR);
|
|
// Get the ISO year, which matches the week of year. This
|
|
// may be one year before or after the calendar year.
|
|
int32_t isoYear = internalGet(YEAR);
|
|
if (internalGet(MONTH) == Calendar::JANUARY) {
|
|
if (woy >= 52) {
|
|
--isoYear;
|
|
}
|
|
}
|
|
else {
|
|
if (woy == 1) {
|
|
++isoYear;
|
|
}
|
|
}
|
|
return isoYear;
|
|
}
|
|
|
|
/**
|
|
* Return the ERA. We need a special method for this because the
|
|
* default ERA is AD, but a zero (unset) ERA is BC.
|
|
*/
|
|
int32_t
|
|
GregorianCalendar::internalGetEra() const {
|
|
return isSet(ERA) ? internalGet(ERA) : AD;
|
|
}
|
|
|
|
//eof
|