{@code GregorianCalendar} is a hybrid calendar that * supports both the Julian and Gregorian calendar systems with the * support of a single discontinuity, which corresponds by default to * the Gregorian date when the Gregorian calendar was instituted * (October 15, 1582 in some countries, later in others). The cutover * date may be changed by the caller by calling {@link * #setGregorianChange(Date) setGregorianChange()}. * *
* Historically, in those countries which adopted the Gregorian calendar first, * October 4, 1582 (Julian) was thus followed by October 15, 1582 (Gregorian). This calendar models * this correctly. Before the Gregorian cutover, {@code GregorianCalendar} * implements the Julian calendar. The only difference between the Gregorian * and the Julian calendar is the leap year rule. The Julian calendar specifies * leap years every four years, whereas the Gregorian calendar omits century * years which are not divisible by 400. * *
* {@code GregorianCalendar} implements proleptic Gregorian and * Julian calendars. That is, dates are computed by extrapolating the current * rules indefinitely far backward and forward in time. As a result, * {@code GregorianCalendar} may be used for all years to generate * meaningful and consistent results. However, dates obtained using * {@code GregorianCalendar} are historically accurate only from March 1, 4 * AD onward, when modern Julian calendar rules were adopted. Before this date, * leap year rules were applied irregularly, and before 45 BC the Julian * calendar did not even exist. * *
* Prior to the institution of the Gregorian calendar, New Year's Day was * March 25. To avoid confusion, this calendar always uses January 1. A manual * adjustment may be made if desired for dates that are prior to the Gregorian * changeover and which fall between January 1 and March 24. * *
Values calculated for the {@link Calendar#WEEK_OF_YEAR * WEEK_OF_YEAR} field range from 1 to 53. The first week of a * calendar year is the earliest seven day period starting on {@link * Calendar#getFirstDayOfWeek() getFirstDayOfWeek()} that contains at * least {@link Calendar#getMinimalDaysInFirstWeek() * getMinimalDaysInFirstWeek()} days from that year. It thus depends * on the values of {@code getMinimalDaysInFirstWeek()}, {@code * getFirstDayOfWeek()}, and the day of the week of January 1. Weeks * between week 1 of one year and week 1 of the following year * (exclusive) are numbered sequentially from 2 to 52 or 53 (except * for year(s) involved in the Julian-Gregorian transition). * *
The {@code getFirstDayOfWeek()} and {@code * getMinimalDaysInFirstWeek()} values are initialized using * locale-dependent resources when constructing a {@code * GregorianCalendar}. The week * determination is compatible with the ISO 8601 standard when {@code * getFirstDayOfWeek()} is {@code MONDAY} and {@code * getMinimalDaysInFirstWeek()} is 4, which values are used in locales * where the standard is preferred. These values can explicitly be set by * calling {@link Calendar#setFirstDayOfWeek(int) setFirstDayOfWeek()} and * {@link Calendar#setMinimalDaysInFirstWeek(int) * setMinimalDaysInFirstWeek()}. * *
A week year is in sync with a * {@code WEEK_OF_YEAR} cycle. All weeks between the first and last * weeks (inclusive) have the same week year value. * Therefore, the first and last days of a week year may have * different calendar year values. * *
For example, January 1, 1998 is a Thursday. If {@code * getFirstDayOfWeek()} is {@code MONDAY} and {@code * getMinimalDaysInFirstWeek()} is 4 (ISO 8601 standard compatible * setting), then week 1 of 1998 starts on December 29, 1997, and ends * on January 4, 1998. The week year is 1998 for the last three days * of calendar year 1997. If, however, {@code getFirstDayOfWeek()} is * {@code SUNDAY}, then week 1 of 1998 starts on January 4, 1998, and * ends on January 10, 1998; the first three days of 1998 then are * part of week 53 of 1997 and their week year is 1997. * *
Values calculated for the {@code WEEK_OF_MONTH} field range from 0
* to 6. Week 1 of a month (the days with WEEK_OF_MONTH =
* 1) is the earliest set of at least
* {@code getMinimalDaysInFirstWeek()} contiguous days in that month,
* ending on the day before {@code getFirstDayOfWeek()}. Unlike
* week 1 of a year, week 1 of a month may be shorter than 7 days, need
* not start on {@code getFirstDayOfWeek()}, and will not include days of
* the previous month. Days of a month before week 1 have a
* {@code WEEK_OF_MONTH} of 0.
*
*
For example, if {@code getFirstDayOfWeek()} is {@code SUNDAY} * and {@code getMinimalDaysInFirstWeek()} is 4, then the first week of * January 1998 is Sunday, January 4 through Saturday, January 10. These days * have a {@code WEEK_OF_MONTH} of 1. Thursday, January 1 through * Saturday, January 3 have a {@code WEEK_OF_MONTH} of 0. If * {@code getMinimalDaysInFirstWeek()} is changed to 3, then January 1 * through January 3 have a {@code WEEK_OF_MONTH} of 1. * *
The {@code clear} method sets calendar field(s) * undefined. {@code GregorianCalendar} uses the following * default value for each calendar field if its value is undefined. * *
| * Field * | ** Default Value * | *
|---|---|
| * {@code ERA} * | ** {@code AD} * | *
| * {@code YEAR} * | ** {@code 1970} * | *
| * {@code MONTH} * | ** {@code JANUARY} * | *
| * {@code DAY_OF_MONTH} * | ** {@code 1} * | *
| * {@code DAY_OF_WEEK} * | ** {@code the first day of week} * | *
| * {@code WEEK_OF_MONTH} * | ** {@code 0} * | *
| * {@code DAY_OF_WEEK_IN_MONTH} * | ** {@code 1} * | *
| * {@code AM_PM} * | ** {@code AM} * | *
| * {@code HOUR, HOUR_OF_DAY, MINUTE, SECOND, MILLISECOND} * | ** {@code 0} * | *
* Example: *
*
* // get the supported ids for GMT-08:00 (Pacific Standard Time)
* String[] ids = TimeZone.getAvailableIDs(-8 * 60 * 60 * 1000);
* // if no ids were returned, something is wrong. get out.
* if (ids.length == 0)
* System.exit(0);
*
* // begin output
* System.out.println("Current Time");
*
* // create a Pacific Standard Time time zone
* SimpleTimeZone pdt = new SimpleTimeZone(-8 * 60 * 60 * 1000, ids[0]);
*
* // set up rules for Daylight Saving Time
* pdt.setStartRule(Calendar.APRIL, 1, Calendar.SUNDAY, 2 * 60 * 60 * 1000);
* pdt.setEndRule(Calendar.OCTOBER, -1, Calendar.SUNDAY, 2 * 60 * 60 * 1000);
*
* // create a GregorianCalendar with the Pacific Daylight time zone
* // and the current date and time
* Calendar calendar = new GregorianCalendar(pdt);
* Date trialTime = new Date();
* calendar.setTime(trialTime);
*
* // print out a bunch of interesting things
* System.out.println("ERA: " + calendar.get(Calendar.ERA));
* System.out.println("YEAR: " + calendar.get(Calendar.YEAR));
* System.out.println("MONTH: " + calendar.get(Calendar.MONTH));
* System.out.println("WEEK_OF_YEAR: " + calendar.get(Calendar.WEEK_OF_YEAR));
* System.out.println("WEEK_OF_MONTH: " + calendar.get(Calendar.WEEK_OF_MONTH));
* System.out.println("DATE: " + calendar.get(Calendar.DATE));
* System.out.println("DAY_OF_MONTH: " + calendar.get(Calendar.DAY_OF_MONTH));
* System.out.println("DAY_OF_YEAR: " + calendar.get(Calendar.DAY_OF_YEAR));
* System.out.println("DAY_OF_WEEK: " + calendar.get(Calendar.DAY_OF_WEEK));
* System.out.println("DAY_OF_WEEK_IN_MONTH: "
* + calendar.get(Calendar.DAY_OF_WEEK_IN_MONTH));
* System.out.println("AM_PM: " + calendar.get(Calendar.AM_PM));
* System.out.println("HOUR: " + calendar.get(Calendar.HOUR));
* System.out.println("HOUR_OF_DAY: " + calendar.get(Calendar.HOUR_OF_DAY));
* System.out.println("MINUTE: " + calendar.get(Calendar.MINUTE));
* System.out.println("SECOND: " + calendar.get(Calendar.SECOND));
* System.out.println("MILLISECOND: " + calendar.get(Calendar.MILLISECOND));
* System.out.println("ZONE_OFFSET: "
* + (calendar.get(Calendar.ZONE_OFFSET)/(60*60*1000)));
* System.out.println("DST_OFFSET: "
* + (calendar.get(Calendar.DST_OFFSET)/(60*60*1000)));
* System.out.println("Current Time, with hour reset to 3");
* calendar.clear(Calendar.HOUR_OF_DAY); // so doesn't override
* calendar.set(Calendar.HOUR, 3);
* System.out.println("ERA: " + calendar.get(Calendar.ERA));
* System.out.println("YEAR: " + calendar.get(Calendar.YEAR));
* System.out.println("MONTH: " + calendar.get(Calendar.MONTH));
* System.out.println("WEEK_OF_YEAR: " + calendar.get(Calendar.WEEK_OF_YEAR));
* System.out.println("WEEK_OF_MONTH: " + calendar.get(Calendar.WEEK_OF_MONTH));
* System.out.println("DATE: " + calendar.get(Calendar.DATE));
* System.out.println("DAY_OF_MONTH: " + calendar.get(Calendar.DAY_OF_MONTH));
* System.out.println("DAY_OF_YEAR: " + calendar.get(Calendar.DAY_OF_YEAR));
* System.out.println("DAY_OF_WEEK: " + calendar.get(Calendar.DAY_OF_WEEK));
* System.out.println("DAY_OF_WEEK_IN_MONTH: "
* + calendar.get(Calendar.DAY_OF_WEEK_IN_MONTH));
* System.out.println("AM_PM: " + calendar.get(Calendar.AM_PM));
* System.out.println("HOUR: " + calendar.get(Calendar.HOUR));
* System.out.println("HOUR_OF_DAY: " + calendar.get(Calendar.HOUR_OF_DAY));
* System.out.println("MINUTE: " + calendar.get(Calendar.MINUTE));
* System.out.println("SECOND: " + calendar.get(Calendar.SECOND));
* System.out.println("MILLISECOND: " + calendar.get(Calendar.MILLISECOND));
* System.out.println("ZONE_OFFSET: "
* + (calendar.get(Calendar.ZONE_OFFSET)/(60*60*1000))); // in hours
* System.out.println("DST_OFFSET: "
* + (calendar.get(Calendar.DST_OFFSET)/(60*60*1000))); // in hours
*
*
*
* @see TimeZone
* @author David Goldsmith, Mark Davis, Chen-Lieh Huang, Alan Liu
* @since 1.1
*/
public class GregorianCalendar extends Calendar {
/*
* Implementation Notes
*
* The epoch is the number of days or milliseconds from some defined
* starting point. The epoch for java.util.Date is used here; that is,
* milliseconds from January 1, 1970 (Gregorian), midnight UTC. Other
* epochs which are used are January 1, year 1 (Gregorian), which is day 1
* of the Gregorian calendar, and December 30, year 0 (Gregorian), which is
* day 1 of the Julian calendar.
*
* We implement the proleptic Julian and Gregorian calendars. This means we
* implement the modern definition of the calendar even though the
* historical usage differs. For example, if the Gregorian change is set
* to new Date(Long.MIN_VALUE), we have a pure Gregorian calendar which
* labels dates preceding the invention of the Gregorian calendar in 1582 as
* if the calendar existed then.
*
* Likewise, with the Julian calendar, we assume a consistent
* 4-year leap year rule, even though the historical pattern of
* leap years is irregular, being every 3 years from 45 BCE
* through 9 BCE, then every 4 years from 8 CE onwards, with no
* leap years in-between. Thus date computations and functions
* such as isLeapYear() are not intended to be historically
* accurate.
*/
//////////////////
// Class Variables
//////////////////
/**
* Value of the {@code ERA} field indicating
* the period before the common era (before Christ), also known as BCE.
* The sequence of years at the transition from {@code BC} to {@code AD} is
* ..., 2 BC, 1 BC, 1 AD, 2 AD,...
*
* @see #ERA
*/
public static final int BC = 0;
/**
* Value of the {@link #ERA} field indicating
* the period before the common era, the same value as {@link #BC}.
*
* @see #CE
*/
static final int BCE = 0;
/**
* Value of the {@code ERA} field indicating
* the common era (Anno Domini), also known as CE.
* The sequence of years at the transition from {@code BC} to {@code AD} is
* ..., 2 BC, 1 BC, 1 AD, 2 AD,...
*
* @see #ERA
*/
public static final int AD = 1;
/**
* Value of the {@link #ERA} field indicating
* the common era, the same value as {@link #AD}.
*
* @see #BCE
*/
static final int CE = 1;
private static final int EPOCH_OFFSET = 719163; // Fixed date of January 1, 1970 (Gregorian)
private static final int EPOCH_YEAR = 1970;
static final int MONTH_LENGTH[]
= {31,28,31,30,31,30,31,31,30,31,30,31}; // 0-based
static final int LEAP_MONTH_LENGTH[]
= {31,29,31,30,31,30,31,31,30,31,30,31}; // 0-based
// Useful millisecond constants. Although ONE_DAY and ONE_WEEK can fit
// into ints, they must be longs in order to prevent arithmetic overflow
// when performing (bug 4173516).
private static final int ONE_SECOND = 1000;
private static final int ONE_MINUTE = 60*ONE_SECOND;
private static final int ONE_HOUR = 60*ONE_MINUTE;
private static final long ONE_DAY = 24*ONE_HOUR;
private static final long ONE_WEEK = 7*ONE_DAY;
/*
*
* Greatest Least
* Field name Minimum Minimum Maximum Maximum
* ---------- ------- ------- ------- -------
* ERA 0 0 1 1
* YEAR 1 1 292269054 292278994
* MONTH 0 0 11 11
* WEEK_OF_YEAR 1 1 52* 53
* WEEK_OF_MONTH 0 0 4* 6
* DAY_OF_MONTH 1 1 28* 31
* DAY_OF_YEAR 1 1 365* 366
* DAY_OF_WEEK 1 1 7 7
* DAY_OF_WEEK_IN_MONTH 1 1 4* 6
* AM_PM 0 0 1 1
* HOUR 0 0 11 11
* HOUR_OF_DAY 0 0 23 23
* MINUTE 0 0 59 59
* SECOND 0 0 59 59
* MILLISECOND 0 0 999 999
* ZONE_OFFSET -13:00 -13:00 14:00 14:00
* DST_OFFSET 0:00 0:00 0:20 2:00
*
* *: depends on the Gregorian change date
*/
static final int MIN_VALUES[] = {
BCE, // ERA
1, // YEAR
JANUARY, // MONTH
1, // WEEK_OF_YEAR
0, // WEEK_OF_MONTH
1, // DAY_OF_MONTH
1, // DAY_OF_YEAR
SUNDAY, // DAY_OF_WEEK
1, // DAY_OF_WEEK_IN_MONTH
AM, // AM_PM
0, // HOUR
0, // HOUR_OF_DAY
0, // MINUTE
0, // SECOND
0, // MILLISECOND
-13*ONE_HOUR, // ZONE_OFFSET (UNIX compatibility)
0 // DST_OFFSET
};
static final int LEAST_MAX_VALUES[] = {
CE, // ERA
292269054, // YEAR
DECEMBER, // MONTH
52, // WEEK_OF_YEAR
4, // WEEK_OF_MONTH
28, // DAY_OF_MONTH
365, // DAY_OF_YEAR
SATURDAY, // DAY_OF_WEEK
4, // DAY_OF_WEEK_IN
PM, // AM_PM
11, // HOUR
23, // HOUR_OF_DAY
59, // MINUTE
59, // SECOND
999, // MILLISECOND
14*ONE_HOUR, // ZONE_OFFSET
20*ONE_MINUTE // DST_OFFSET (historical least maximum)
};
static final int MAX_VALUES[] = {
CE, // ERA
292278994, // YEAR
DECEMBER, // MONTH
53, // WEEK_OF_YEAR
6, // WEEK_OF_MONTH
31, // DAY_OF_MONTH
366, // DAY_OF_YEAR
SATURDAY, // DAY_OF_WEEK
6, // DAY_OF_WEEK_IN
PM, // AM_PM
11, // HOUR
23, // HOUR_OF_DAY
59, // MINUTE
59, // SECOND
999, // MILLISECOND
14*ONE_HOUR, // ZONE_OFFSET
2*ONE_HOUR // DST_OFFSET (double summer time)
};
// Proclaim serialization compatibility with JDK 1.1
@SuppressWarnings("FieldNameHidesFieldInSuperclass")
@java.io.Serial
static final long serialVersionUID = -8125100834729963327L;
// Reference to the sun.util.calendar.Gregorian instance (singleton).
private static final Gregorian gcal =
CalendarSystem.getGregorianCalendar();
// Reference to the JulianCalendar instance (singleton), set as needed. See
// getJulianCalendarSystem().
private static JulianCalendar jcal;
// JulianCalendar eras. See getJulianCalendarSystem().
private static Era[] jeras;
// The default value of gregorianCutover.
static final long DEFAULT_GREGORIAN_CUTOVER = -12219292800000L;
/////////////////////
// Instance Variables
/////////////////////
/**
* The point at which the Gregorian calendar rules are used, measured in
* milliseconds from the standard epoch. Default is October 15, 1582
* (Gregorian) 00:00:00 UTC or -12219292800000L. For this value, October 4,
* 1582 (Julian) is followed by October 15, 1582 (Gregorian). This
* corresponds to Julian day number 2299161.
* @serial
*/
private long gregorianCutover = DEFAULT_GREGORIAN_CUTOVER;
/**
* The fixed date of the gregorianCutover.
*/
private transient long gregorianCutoverDate =
(((DEFAULT_GREGORIAN_CUTOVER + 1)/ONE_DAY) - 1) + EPOCH_OFFSET; // == 577736
/**
* The normalized year of the gregorianCutover in Gregorian, with
* 0 representing 1 BCE, -1 representing 2 BCE, etc.
*/
private transient int gregorianCutoverYear = 1582;
/**
* The normalized year of the gregorianCutover in Julian, with 0
* representing 1 BCE, -1 representing 2 BCE, etc.
*/
private transient int gregorianCutoverYearJulian = 1582;
/**
* gdate always has a sun.util.calendar.Gregorian.Date instance to
* avoid overhead of creating it. The assumption is that most
* applications will need only Gregorian calendar calculations.
*/
private transient BaseCalendar.Date gdate;
/**
* Reference to either gdate or a JulianCalendar.Date
* instance. After calling complete(), this value is guaranteed to
* be set.
*/
private transient BaseCalendar.Date cdate;
/**
* The CalendarSystem used to calculate the date in cdate. After
* calling complete(), this value is guaranteed to be set and
* consistent with the cdate value.
*/
private transient BaseCalendar calsys;
/**
* Temporary int[2] to get time zone offsets. zoneOffsets[0] gets
* the GMT offset value and zoneOffsets[1] gets the DST saving
* value.
*/
private transient int[] zoneOffsets;
/**
* Temporary storage for saving original fields[] values in
* non-lenient mode.
*/
private transient int[] originalFields;
///////////////
// Constructors
///////////////
/**
* Constructs a default {@code GregorianCalendar} using the current time
* in the default time zone with the default
* {@link Locale.Category#FORMAT FORMAT} locale.
*/
public GregorianCalendar() {
this(TimeZone.getDefaultRef(), Locale.getDefault(Locale.Category.FORMAT));
setZoneShared(true);
}
/**
* Constructs a {@code GregorianCalendar} based on the current time
* in the given time zone with the default
* {@link Locale.Category#FORMAT FORMAT} locale.
*
* @param zone the given time zone.
*/
public GregorianCalendar(TimeZone zone) {
this(zone, Locale.getDefault(Locale.Category.FORMAT));
}
/**
* Constructs a {@code GregorianCalendar} based on the current time
* in the default time zone with the given locale.
*
* @param aLocale the given locale.
*/
public GregorianCalendar(Locale aLocale) {
this(TimeZone.getDefaultRef(), aLocale);
setZoneShared(true);
}
/**
* Constructs a {@code GregorianCalendar} based on the current time
* in the given time zone with the given locale.
*
* @param zone the given time zone.
* @param aLocale the given locale.
*/
public GregorianCalendar(TimeZone zone, Locale aLocale) {
super(zone, aLocale);
gdate = (BaseCalendar.Date) gcal.newCalendarDate(zone);
setTimeInMillis(System.currentTimeMillis());
}
/**
* Constructs a {@code GregorianCalendar} with the given date set
* in the default time zone with the default locale.
*
* @param year the value used to set the {@code YEAR} calendar field in the calendar.
* @param month the value used to set the {@code MONTH} calendar field in the calendar.
* Month value is 0-based. e.g., 0 for January.
* @param dayOfMonth the value used to set the {@code DAY_OF_MONTH} calendar field in the calendar.
*/
public GregorianCalendar(int year, int month, int dayOfMonth) {
this(year, month, dayOfMonth, 0, 0, 0, 0);
}
/**
* Constructs a {@code GregorianCalendar} with the given date
* and time set for the default time zone with the default locale.
*
* @param year the value used to set the {@code YEAR} calendar field in the calendar.
* @param month the value used to set the {@code MONTH} calendar field in the calendar.
* Month value is 0-based. e.g., 0 for January.
* @param dayOfMonth the value used to set the {@code DAY_OF_MONTH} calendar field in the calendar.
* @param hourOfDay the value used to set the {@code HOUR_OF_DAY} calendar field
* in the calendar.
* @param minute the value used to set the {@code MINUTE} calendar field
* in the calendar.
*/
public GregorianCalendar(int year, int month, int dayOfMonth, int hourOfDay,
int minute) {
this(year, month, dayOfMonth, hourOfDay, minute, 0, 0);
}
/**
* Constructs a GregorianCalendar with the given date
* and time set for the default time zone with the default locale.
*
* @param year the value used to set the {@code YEAR} calendar field in the calendar.
* @param month the value used to set the {@code MONTH} calendar field in the calendar.
* Month value is 0-based. e.g., 0 for January.
* @param dayOfMonth the value used to set the {@code DAY_OF_MONTH} calendar field in the calendar.
* @param hourOfDay the value used to set the {@code HOUR_OF_DAY} calendar field
* in the calendar.
* @param minute the value used to set the {@code MINUTE} calendar field
* in the calendar.
* @param second the value used to set the {@code SECOND} calendar field
* in the calendar.
*/
public GregorianCalendar(int year, int month, int dayOfMonth, int hourOfDay,
int minute, int second) {
this(year, month, dayOfMonth, hourOfDay, minute, second, 0);
}
/**
* Constructs a {@code GregorianCalendar} with the given date
* and time set for the default time zone with the default locale.
*
* @param year the value used to set the {@code YEAR} calendar field in the calendar.
* @param month the value used to set the {@code MONTH} calendar field in the calendar.
* Month value is 0-based. e.g., 0 for January.
* @param dayOfMonth the value used to set the {@code DAY_OF_MONTH} calendar field in the calendar.
* @param hourOfDay the value used to set the {@code HOUR_OF_DAY} calendar field
* in the calendar.
* @param minute the value used to set the {@code MINUTE} calendar field
* in the calendar.
* @param second the value used to set the {@code SECOND} calendar field
* in the calendar.
* @param millis the value used to set the {@code MILLISECOND} calendar field
*/
GregorianCalendar(int year, int month, int dayOfMonth,
int hourOfDay, int minute, int second, int millis) {
super();
gdate = (BaseCalendar.Date) gcal.newCalendarDate(getZone());
this.set(YEAR, year);
this.set(MONTH, month);
this.set(DAY_OF_MONTH, dayOfMonth);
// Set AM_PM and HOUR here to set their stamp values before
// setting HOUR_OF_DAY (6178071).
if (hourOfDay >= 12 && hourOfDay <= 23) {
// If hourOfDay is a valid PM hour, set the correct PM values
// so that it won't throw an exception in case it's set to
// non-lenient later.
this.internalSet(AM_PM, PM);
this.internalSet(HOUR, hourOfDay - 12);
} else {
// The default value for AM_PM is AM.
// We don't care any out of range value here for leniency.
this.internalSet(HOUR, hourOfDay);
}
// The stamp values of AM_PM and HOUR must be COMPUTED. (6440854)
setFieldsComputed(HOUR_MASK|AM_PM_MASK);
this.set(HOUR_OF_DAY, hourOfDay);
this.set(MINUTE, minute);
this.set(SECOND, second);
// should be changed to set() when this constructor is made
// public.
this.internalSet(MILLISECOND, millis);
}
/**
* Constructs an empty GregorianCalendar.
*
* @param zone the given time zone
* @param locale the given locale
* @param flag the flag requesting an empty instance
*/
GregorianCalendar(TimeZone zone, Locale locale, boolean flag) {
super(zone, locale);
gdate = (BaseCalendar.Date) gcal.newCalendarDate(getZone());
}
// BEGIN Android-added: Constructor.
GregorianCalendar(long milliseconds) {
this();
setTimeInMillis(milliseconds);
}
// END Android-added: Constructor.
/////////////////
// Public methods
/////////////////
/**
* Sets the {@code GregorianCalendar} change date. This is the point when the switch
* from Julian dates to Gregorian dates occurred. Default is October 15,
* 1582 (Gregorian). Previous to this, dates will be in the Julian calendar.
* * To obtain a pure Julian calendar, set the change date to * {@code Date(Long.MAX_VALUE)}. To obtain a pure Gregorian calendar, * set the change date to {@code Date(Long.MIN_VALUE)}. * * @param date the given Gregorian cutover date. */ public void setGregorianChange(Date date) { long cutoverTime = date.getTime(); if (cutoverTime == gregorianCutover) { return; } // Before changing the cutover date, make sure to have the // time of this calendar. complete(); setGregorianChange(cutoverTime); } private void setGregorianChange(long cutoverTime) { gregorianCutover = cutoverTime; gregorianCutoverDate = CalendarUtils.floorDivide(cutoverTime, ONE_DAY) + EPOCH_OFFSET; // To provide the "pure" Julian calendar as advertised. // Strictly speaking, the last millisecond should be a // Gregorian date. However, the API doc specifies that setting // the cutover date to Long.MAX_VALUE will make this calendar // a pure Julian calendar. (See 4167995) if (cutoverTime == Long.MAX_VALUE) { gregorianCutoverDate++; } BaseCalendar.Date d = getGregorianCutoverDate(); // Set the cutover year (in the Gregorian year numbering) gregorianCutoverYear = d.getYear(); BaseCalendar julianCal = getJulianCalendarSystem(); d = (BaseCalendar.Date) julianCal.newCalendarDate(TimeZone.NO_TIMEZONE); julianCal.getCalendarDateFromFixedDate(d, gregorianCutoverDate - 1); gregorianCutoverYearJulian = d.getNormalizedYear(); if (time < gregorianCutover) { // The field values are no longer valid under the new // cutover date. setUnnormalized(); } } /** * Gets the Gregorian Calendar change date. This is the point when the * switch from Julian dates to Gregorian dates occurred. Default is * October 15, 1582 (Gregorian). Previous to this, dates will be in the Julian * calendar. * * @return the Gregorian cutover date for this {@code GregorianCalendar} object. */ public final Date getGregorianChange() { return new Date(gregorianCutover); } /** * Determines if the given year is a leap year. Returns {@code true} if * the given year is a leap year. To specify BC year numbers, * {@code 1 - year number} must be given. For example, year BC 4 is * specified as -3. * * @param year the given year. * @return {@code true} if the given year is a leap year; {@code false} otherwise. */ public boolean isLeapYear(int year) { if ((year & 3) != 0) { return false; } if (year > gregorianCutoverYear) { return (year%100 != 0) || (year%400 == 0); // Gregorian } if (year < gregorianCutoverYearJulian) { return true; // Julian } boolean gregorian; // If the given year is the Gregorian cutover year, we need to // determine which calendar system to be applied to February in the year. if (gregorianCutoverYear == gregorianCutoverYearJulian) { BaseCalendar.Date d = getCalendarDate(gregorianCutoverDate); // Gregorian gregorian = d.getMonth() < BaseCalendar.MARCH; } else { gregorian = year == gregorianCutoverYear; } return gregorian ? (year%100 != 0) || (year%400 == 0) : true; } /** * Returns {@code "gregory"} as the calendar type. * * @return {@code "gregory"} * @since 1.8 */ @Override public String getCalendarType() { return "gregory"; } /** * Compares this {@code GregorianCalendar} to the specified * {@code Object}. The result is {@code true} if and * only if the argument is a {@code GregorianCalendar} object * that represents the same time value (millisecond offset from * the Epoch) under the same * {@code Calendar} parameters and Gregorian change date as * this object. * * @param obj the object to compare with. * @return {@code true} if this object is equal to {@code obj}; * {@code false} otherwise. * @see Calendar#compareTo(Calendar) */ @Override public boolean equals(Object obj) { return obj instanceof GregorianCalendar && super.equals(obj) && gregorianCutover == ((GregorianCalendar)obj).gregorianCutover; } /** * Generates the hash code for this {@code GregorianCalendar} object. */ @Override public int hashCode() { return super.hashCode() ^ (int)gregorianCutoverDate; } /** * Adds the specified (signed) amount of time to the given calendar field, * based on the calendar's rules. * *
Add rule 1. The value of {@code field} * after the call minus the value of {@code field} before the * call is {@code amount}, modulo any overflow that has occurred in * {@code field}. Overflow occurs when a field value exceeds its * range and, as a result, the next larger field is incremented or * decremented and the field value is adjusted back into its range.
* *Add rule 2. If a smaller field is expected to be * invariant, but it is impossible for it to be equal to its * prior value because of changes in its minimum or maximum after * {@code field} is changed, then its value is adjusted to be as close * as possible to its expected value. A smaller field represents a * smaller unit of time. {@code HOUR} is a smaller field than * {@code DAY_OF_MONTH}. No adjustment is made to smaller fields * that are not expected to be invariant. The calendar system * determines what fields are expected to be invariant.
* * @param field the calendar field. * @param amount the amount of date or time to be added to the field. * @throws IllegalArgumentException if {@code field} is * {@code ZONE_OFFSET}, {@code DST_OFFSET}, or unknown, * or if any calendar fields have out-of-range values in * non-lenient mode. */ @Override public void add(int field, int amount) { // If amount == 0, do nothing even the given field is out of // range. This is tested by JCK. if (amount == 0) { return; // Do nothing! } if (field < 0 || field >= ZONE_OFFSET) { throw new IllegalArgumentException(); } // Sync the time and calendar fields. complete(); if (field == YEAR) { int year = internalGet(YEAR); if (internalGetEra() == CE) { year += amount; if (year > 0) { set(YEAR, year); } else { // year <= 0 set(YEAR, 1 - year); // if year == 0, you get 1 BCE. set(ERA, BCE); } } else { // era == BCE year -= amount; if (year > 0) { set(YEAR, year); } else { // year <= 0 set(YEAR, 1 - year); // if year == 0, you get 1 CE set(ERA, CE); } } pinDayOfMonth(); } else if (field == MONTH) { int month = internalGet(MONTH) + amount; int year = internalGet(YEAR); int y_amount; if (month >= 0) { y_amount = month/12; } else { y_amount = (month+1)/12 - 1; } if (y_amount != 0) { if (internalGetEra() == CE) { year += y_amount; if (year > 0) { set(YEAR, year); } else { // year <= 0 set(YEAR, 1 - year); // if year == 0, you get 1 BCE set(ERA, BCE); } } else { // era == BCE year -= y_amount; if (year > 0) { set(YEAR, year); } else { // year <= 0 set(YEAR, 1 - year); // if year == 0, you get 1 CE set(ERA, CE); } } } if (month >= 0) { set(MONTH, month % 12); } else { // month < 0 month %= 12; if (month < 0) { month += 12; } set(MONTH, JANUARY + month); } pinDayOfMonth(); } else if (field == ERA) { int era = internalGet(ERA) + amount; if (era < 0) { era = 0; } if (era > 1) { era = 1; } set(ERA, era); } else { long delta = amount; long timeOfDay = 0; switch (field) { // Handle the time fields here. Convert the given // amount to milliseconds and call setTimeInMillis. case HOUR: case HOUR_OF_DAY: delta *= 60 * 60 * 1000; // hours to minutes break; case MINUTE: delta *= 60 * 1000; // minutes to seconds break; case SECOND: delta *= 1000; // seconds to milliseconds break; case MILLISECOND: break; // Handle week, day and AM_PM fields which involves // time zone offset change adjustment. Convert the // given amount to the number of days. case WEEK_OF_YEAR: case WEEK_OF_MONTH: case DAY_OF_WEEK_IN_MONTH: delta *= 7; break; case DAY_OF_MONTH: // synonym of DATE case DAY_OF_YEAR: case DAY_OF_WEEK: break; case AM_PM: // Convert the amount to the number of days (delta) // and +12 or -12 hours (timeOfDay). delta = amount / 2; timeOfDay = 12 * (amount % 2); break; } // The time fields don't require time zone offset change // adjustment. if (field >= HOUR) { setTimeInMillis(time + delta); return; } // The rest of the fields (week, day or AM_PM fields) // require time zone offset (both GMT and DST) change // adjustment. // Translate the current time to the fixed date and time // of the day. long fd = getCurrentFixedDate(); timeOfDay += internalGet(HOUR_OF_DAY); timeOfDay *= 60; timeOfDay += internalGet(MINUTE); timeOfDay *= 60; timeOfDay += internalGet(SECOND); timeOfDay *= 1000; timeOfDay += internalGet(MILLISECOND); if (timeOfDay >= ONE_DAY) { fd++; timeOfDay -= ONE_DAY; } else if (timeOfDay < 0) { fd--; timeOfDay += ONE_DAY; } fd += delta; // fd is the expected fixed date after the calculation // BEGIN Android-changed: time zone related calculation via helper methods. // Calculate the time in the UTC time zone. long utcTime = (fd - EPOCH_OFFSET) * ONE_DAY + timeOfDay; // Neither of the time zone related fields are relevant because they have not been // set since the call to complete() above. int tzMask = 0; // Adjust the time to account for zone and daylight savings time offset. long millis = adjustForZoneAndDaylightSavingsTime(tzMask, utcTime, getZone()); // Update the time and recompute the fields. setTimeInMillis(millis); // END Android-changed: time zone related calculation via helper methods. } } /** * Adds or subtracts (up/down) a single unit of time on the given time * field without changing larger fields. ** Example: Consider a {@code GregorianCalendar} * originally set to December 31, 1999. Calling {@link #roll(int,boolean) roll(Calendar.MONTH, true)} * sets the calendar to January 31, 1999. The {@code YEAR} field is unchanged * because it is a larger field than {@code MONTH}.
* * @param up indicates if the value of the specified calendar field is to be * rolled up or rolled down. Use {@code true} if rolling up, {@code false} otherwise. * @throws IllegalArgumentException if {@code field} is * {@code ZONE_OFFSET}, {@code DST_OFFSET}, or unknown, * or if any calendar fields have out-of-range values in * non-lenient mode. * @see #add(int,int) * @see #set(int,int) */ @Override public void roll(int field, boolean up) { roll(field, up ? +1 : -1); } /** * Adds a signed amount to the specified calendar field without changing larger fields. * A negative roll amount means to subtract from field without changing * larger fields. If the specified amount is 0, this method performs nothing. * *This method calls {@link #complete()} before adding the * amount so that all the calendar fields are normalized. If there * is any calendar field having an out-of-range value in non-lenient mode, then an * {@code IllegalArgumentException} is thrown. * *
* Example: Consider a {@code GregorianCalendar}
* originally set to August 31, 1999. Calling roll(Calendar.MONTH,
* 8) sets the calendar to April 30, 1999. Using a
* {@code GregorianCalendar}, the {@code DAY_OF_MONTH} field cannot
* be 31 in the month April. {@code DAY_OF_MONTH} is set to the closest possible
* value, 30. The {@code YEAR} field maintains the value of 1999 because it
* is a larger field than {@code MONTH}.
*
* Example: Consider a {@code GregorianCalendar} * originally set to Sunday June 6, 1999. Calling * {@code roll(Calendar.WEEK_OF_MONTH, -1)} sets the calendar to * Tuesday June 1, 1999, whereas calling * {@code add(Calendar.WEEK_OF_MONTH, -1)} sets the calendar to * Sunday May 30, 1999. This is because the roll rule imposes an * additional constraint: The {@code MONTH} must not change when the * {@code WEEK_OF_MONTH} is rolled. Taken together with add rule 1, * the resultant date must be between Tuesday June 1 and Saturday June * 5. According to add rule 2, the {@code DAY_OF_WEEK}, an invariant * when changing the {@code WEEK_OF_MONTH}, is set to Tuesday, the * closest possible value to Sunday (where Sunday is the first day of the * week).
* * @param field the calendar field. * @param amount the signed amount to add to {@code field}. * @throws IllegalArgumentException if {@code field} is * {@code ZONE_OFFSET}, {@code DST_OFFSET}, or unknown, * or if any calendar fields have out-of-range values in * non-lenient mode. * @see #roll(int,boolean) * @see #add(int,int) * @see #set(int,int) * @since 1.2 */ @Override public void roll(int field, int amount) { // If amount == 0, do nothing even the given field is out of // range. This is tested by JCK. if (amount == 0) { return; } if (field < 0 || field >= ZONE_OFFSET) { throw new IllegalArgumentException(); } // Sync the time and calendar fields. complete(); int min = getMinimum(field); int max = getMaximum(field); switch (field) { case AM_PM: case ERA: case YEAR: 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: { int rolledValue = getRolledValue(internalGet(field), amount, min, max); int hourOfDay = rolledValue; if (field == HOUR && internalGet(AM_PM) == PM) { hourOfDay += 12; } // Create the current date/time value to perform wall-clock-based // roll. CalendarDate d = calsys.getCalendarDate(time, getZone()); d.setHours(hourOfDay); time = calsys.getTime(d); // If we stay on the same wall-clock time, try the next or previous hour. if (internalGet(HOUR_OF_DAY) == d.getHours()) { hourOfDay = getRolledValue(rolledValue, amount > 0 ? +1 : -1, min, max); if (field == HOUR && internalGet(AM_PM) == PM) { hourOfDay += 12; } d.setHours(hourOfDay); time = calsys.getTime(d); } // Get the new hourOfDay value which might have changed due to a DST transition. hourOfDay = d.getHours(); // Update the hour related fields internalSet(HOUR_OF_DAY, hourOfDay); internalSet(AM_PM, hourOfDay / 12); internalSet(HOUR, hourOfDay % 12); // Time zone offset and/or daylight saving might have changed. int zoneOffset = d.getZoneOffset(); int saving = d.getDaylightSaving(); internalSet(ZONE_OFFSET, zoneOffset - saving); internalSet(DST_OFFSET, saving); 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.,For example, if the Gregorian change date is January 10, * 1970 and the date of this {@code GregorianCalendar} is * January 20, 1970, the actual minimum value of the * {@code DAY_OF_MONTH} field is 10 because the previous date * of January 10, 1970 is December 27, 1996 (in the Julian * calendar). Therefore, December 28, 1969 to January 9, 1970 * don't exist. * * @param field the calendar field * @return the minimum of the given field for the time value of * this {@code GregorianCalendar} * @see #getMinimum(int) * @see #getMaximum(int) * @see #getGreatestMinimum(int) * @see #getLeastMaximum(int) * @see #getActualMaximum(int) * @since 1.2 */ @Override public int getActualMinimum(int field) { if (field == DAY_OF_MONTH) { GregorianCalendar gc = getNormalizedCalendar(); int year = gc.cdate.getNormalizedYear(); if (year == gregorianCutoverYear || year == gregorianCutoverYearJulian) { long month1 = getFixedDateMonth1(gc.cdate, gc.calsys.getFixedDate(gc.cdate)); BaseCalendar.Date d = getCalendarDate(month1); return d.getDayOfMonth(); } } return getMinimum(field); } /** * Returns the maximum value that this calendar field could have, * taking into consideration the given time value and the current * values of the * {@link Calendar#getFirstDayOfWeek() getFirstDayOfWeek}, * {@link Calendar#getMinimalDaysInFirstWeek() getMinimalDaysInFirstWeek}, * {@link #getGregorianChange() getGregorianChange} and * {@link Calendar#getTimeZone() getTimeZone} methods. * For example, if the date of this instance is February 1, 2004, * the actual maximum value of the {@code DAY_OF_MONTH} field * is 29 because 2004 is a leap year, and if the date of this * instance is February 1, 2005, it's 28. * *
This method calculates the maximum value of {@link
* Calendar#WEEK_OF_YEAR WEEK_OF_YEAR} based on the {@link
* Calendar#YEAR YEAR} (calendar year) value, not the week year. Call {@link
* #getWeeksInWeekYear()} to get the maximum value of {@code
* WEEK_OF_YEAR} in the week year of this {@code GregorianCalendar}.
*
* @param field the calendar field
* @return the maximum of the given field for the time value of
* this {@code GregorianCalendar}
* @see #getMinimum(int)
* @see #getMaximum(int)
* @see #getGreatestMinimum(int)
* @see #getLeastMaximum(int)
* @see #getActualMinimum(int)
* @since 1.2
*/
@Override
public int getActualMaximum(int field) {
final int fieldsForFixedMax = ERA_MASK|DAY_OF_WEEK_MASK|HOUR_MASK|AM_PM_MASK|
HOUR_OF_DAY_MASK|MINUTE_MASK|SECOND_MASK|MILLISECOND_MASK|
ZONE_OFFSET_MASK|DST_OFFSET_MASK;
if ((fieldsForFixedMax & (1< This method calls {@link Calendar#complete()} before
* calculating the week year.
*
* @return the week year represented by this {@code GregorianCalendar}.
* If the {@link Calendar#ERA ERA} value is {@link #BC}, the year is
* represented by 0 or a negative number: BC 1 is 0, BC 2
* is -1, BC 3 is -2, and so on.
* @throws IllegalArgumentException
* if any of the calendar fields is invalid in non-lenient mode.
* @see #isWeekDateSupported()
* @see #getWeeksInWeekYear()
* @see Calendar#getFirstDayOfWeek()
* @see Calendar#getMinimalDaysInFirstWeek()
* @since 1.7
*/
@Override
public int getWeekYear() {
int year = get(YEAR); // implicitly calls complete()
if (internalGetEra() == BCE) {
year = 1 - year;
}
// Fast path for the Gregorian calendar years that are never
// affected by the Julian-Gregorian transition
if (year > gregorianCutoverYear + 1) {
int weekOfYear = internalGet(WEEK_OF_YEAR);
if (internalGet(MONTH) == JANUARY) {
if (weekOfYear >= 52) {
--year;
}
} else {
if (weekOfYear == 1) {
++year;
}
}
return year;
}
// General (slow) path
int dayOfYear = internalGet(DAY_OF_YEAR);
int maxDayOfYear = getActualMaximum(DAY_OF_YEAR);
int minimalDays = getMinimalDaysInFirstWeek();
// Quickly check the possibility of year adjustments before
// cloning this GregorianCalendar.
if (dayOfYear > minimalDays && dayOfYear < (maxDayOfYear - 6)) {
return year;
}
// Create a clone to work on the calculation
GregorianCalendar cal = (GregorianCalendar) clone();
cal.setLenient(true);
// Use GMT so that intermediate date calculations won't
// affect the time of day fields.
cal.setTimeZone(TimeZone.getTimeZone("GMT"));
// Go to the first day of the year, which is usually January 1.
cal.set(DAY_OF_YEAR, 1);
cal.complete();
// Get the first day of the first day-of-week in the year.
int delta = getFirstDayOfWeek() - cal.get(DAY_OF_WEEK);
if (delta != 0) {
if (delta < 0) {
delta += 7;
}
cal.add(DAY_OF_YEAR, delta);
}
int minDayOfYear = cal.get(DAY_OF_YEAR);
if (dayOfYear < minDayOfYear) {
if (minDayOfYear <= minimalDays) {
--year;
}
} else {
cal.set(YEAR, year + 1);
cal.set(DAY_OF_YEAR, 1);
cal.complete();
int del = getFirstDayOfWeek() - cal.get(DAY_OF_WEEK);
if (del != 0) {
if (del < 0) {
del += 7;
}
cal.add(DAY_OF_YEAR, del);
}
minDayOfYear = cal.get(DAY_OF_YEAR) - 1;
if (minDayOfYear == 0) {
minDayOfYear = 7;
}
if (minDayOfYear >= minimalDays) {
int days = maxDayOfYear - dayOfYear + 1;
if (days <= (7 - minDayOfYear)) {
++year;
}
}
}
return year;
}
/**
* Sets this {@code GregorianCalendar} to the date given by the
* date specifiers - {@code weekYear},
* {@code weekOfYear}, and {@code dayOfWeek}. {@code weekOfYear}
* follows the {@code WEEK_OF_YEAR}
* numbering. The {@code dayOfWeek} value must be one of the
* {@link Calendar#DAY_OF_WEEK DAY_OF_WEEK} values: {@link
* Calendar#SUNDAY SUNDAY} to {@link Calendar#SATURDAY SATURDAY}.
*
* Note that the numeric day-of-week representation differs from
* the ISO 8601 standard, and that the {@code weekOfYear}
* numbering is compatible with the standard when {@code
* getFirstDayOfWeek()} is {@code MONDAY} and {@code
* getMinimalDaysInFirstWeek()} is 4.
*
* Unlike the {@code set} method, all of the calendar fields
* and the instant of time value are calculated upon return.
*
* If {@code weekOfYear} is out of the valid week-of-year
* range in {@code weekYear}, the {@code weekYear}
* and {@code weekOfYear} values are adjusted in lenient
* mode, or an {@code IllegalArgumentException} is thrown in
* non-lenient mode.
*
* @param weekYear the week year
* @param weekOfYear the week number based on {@code weekYear}
* @param dayOfWeek the day of week value: one of the constants
* for the {@link #DAY_OF_WEEK DAY_OF_WEEK} field:
* {@link Calendar#SUNDAY SUNDAY}, ...,
* {@link Calendar#SATURDAY SATURDAY}.
* @throws IllegalArgumentException
* if any of the given date specifiers is invalid,
* or if any of the calendar fields are inconsistent
* with the given date specifiers in non-lenient mode
* @see GregorianCalendar#isWeekDateSupported()
* @see Calendar#getFirstDayOfWeek()
* @see Calendar#getMinimalDaysInFirstWeek()
* @since 1.7
*/
@Override
public void setWeekDate(int weekYear, int weekOfYear, int dayOfWeek) {
if (dayOfWeek < SUNDAY || dayOfWeek > SATURDAY) {
throw new IllegalArgumentException("invalid dayOfWeek: " + dayOfWeek);
}
// To avoid changing the time of day fields by date
// calculations, use a clone with the GMT time zone.
GregorianCalendar gc = (GregorianCalendar) clone();
gc.setLenient(true);
int era = gc.get(ERA);
gc.clear();
gc.setTimeZone(TimeZone.getTimeZone("GMT"));
gc.set(ERA, era);
gc.set(YEAR, weekYear);
gc.set(WEEK_OF_YEAR, 1);
gc.set(DAY_OF_WEEK, getFirstDayOfWeek());
int days = dayOfWeek - getFirstDayOfWeek();
if (days < 0) {
days += 7;
}
days += 7 * (weekOfYear - 1);
if (days != 0) {
gc.add(DAY_OF_YEAR, days);
} else {
gc.complete();
}
if (!isLenient() &&
(gc.getWeekYear() != weekYear
|| gc.internalGet(WEEK_OF_YEAR) != weekOfYear
|| gc.internalGet(DAY_OF_WEEK) != dayOfWeek)) {
throw new IllegalArgumentException();
}
set(ERA, gc.internalGet(ERA));
set(YEAR, gc.internalGet(YEAR));
set(MONTH, gc.internalGet(MONTH));
set(DAY_OF_MONTH, gc.internalGet(DAY_OF_MONTH));
// to avoid throwing an IllegalArgumentException in
// non-lenient, set WEEK_OF_YEAR internally
internalSet(WEEK_OF_YEAR, weekOfYear);
complete();
}
/**
* Returns the number of weeks in the week year
* represented by this {@code GregorianCalendar}.
*
* For example, if this {@code GregorianCalendar}'s date is
* December 31, 2008 with the ISO
* 8601 compatible setting, this method will return 53 for the
* period: December 29, 2008 to January 3, 2010 while {@link
* #getActualMaximum(int) getActualMaximum(WEEK_OF_YEAR)} will return
* 52 for the period: December 31, 2007 to December 28, 2008.
*
* @return the number of weeks in the week year.
* @see Calendar#WEEK_OF_YEAR
* @see #getWeekYear()
* @see #getActualMaximum(int)
* @since 1.7
*/
@Override
public int getWeeksInWeekYear() {
GregorianCalendar gc = getNormalizedCalendar();
int weekYear = gc.getWeekYear();
if (weekYear == gc.internalGet(YEAR)) {
return gc.getActualMaximum(WEEK_OF_YEAR);
}
// Use the 2nd week for calculating the max of WEEK_OF_YEAR
if (gc == this) {
gc = (GregorianCalendar) gc.clone();
}
gc.setWeekDate(weekYear, 2, internalGet(DAY_OF_WEEK));
return gc.getActualMaximum(WEEK_OF_YEAR);
}
/////////////////////////////
// Time => Fields computation
/////////////////////////////
/**
* The fixed date corresponding to gdate. If the value is
* Long.MIN_VALUE, the fixed date value is unknown. Currently,
* Julian calendar dates are not cached.
*/
private transient long cachedFixedDate = Long.MIN_VALUE;
/**
* Converts the time value (millisecond offset from the Epoch) to calendar field values.
* The time is not
* recomputed first; to recompute the time, then the fields, call the
* {@code complete} method.
*
* @see Calendar#complete
*/
@Override
protected void computeFields() {
int mask;
if (isPartiallyNormalized()) {
// Determine which calendar fields need to be computed.
mask = getSetStateFields();
int fieldMask = ~mask & ALL_FIELDS;
// We have to call computTime in case calsys == null in
// order to set calsys and cdate. (6263644)
if (fieldMask != 0 || calsys == null) {
mask |= computeFields(fieldMask,
mask & (ZONE_OFFSET_MASK|DST_OFFSET_MASK));
assert mask == ALL_FIELDS;
}
} else {
mask = ALL_FIELDS;
computeFields(mask, 0);
}
// After computing all the fields, set the field state to `COMPUTED'.
setFieldsComputed(mask);
}
/**
* This computeFields implements the conversion from UTC
* (millisecond offset from the Epoch) to calendar
* field values. fieldMask specifies which fields to change the
* setting state to COMPUTED, although all fields are set to
* the correct values. This is required to fix 4685354.
*
* @param fieldMask a bit mask to specify which fields to change
* the setting state.
* @param tzMask a bit mask to specify which time zone offset
* fields to be used for time calculations
* @return a new field mask that indicates what field values have
* actually been set.
*/
private int computeFields(int fieldMask, int tzMask) {
int zoneOffset = 0;
TimeZone tz = getZone();
if (zoneOffsets == null) {
zoneOffsets = new int[2];
}
if (tzMask != (ZONE_OFFSET_MASK|DST_OFFSET_MASK)) {
if (tz instanceof ZoneInfo) {
// BEGIN Android-changed: use libcore.util.ZoneInfo.
// The method name to get offsets differs from sun.util.calendar.ZoneInfo
// zoneOffset = ((ZoneInfo)tz).getOffsets(time, zoneOffsets);
ZoneInfo zoneInfo = (ZoneInfo) tz;
zoneOffset = zoneInfo.getOffsetsByUtcTime(time, zoneOffsets);
// END Android-changed: use libcore.util.ZoneInfo.
} else {
zoneOffset = tz.getOffset(time);
zoneOffsets[0] = tz.getRawOffset();
zoneOffsets[1] = zoneOffset - zoneOffsets[0];
}
}
if (tzMask != 0) {
if (isFieldSet(tzMask, ZONE_OFFSET)) {
zoneOffsets[0] = internalGet(ZONE_OFFSET);
}
if (isFieldSet(tzMask, DST_OFFSET)) {
zoneOffsets[1] = internalGet(DST_OFFSET);
}
zoneOffset = zoneOffsets[0] + zoneOffsets[1];
}
// By computing time and zoneOffset separately, we can take
// the wider range of time+zoneOffset than the previous
// implementation.
long fixedDate = zoneOffset / ONE_DAY;
int timeOfDay = zoneOffset % (int)ONE_DAY;
fixedDate += time / ONE_DAY;
timeOfDay += (int) (time % ONE_DAY);
if (timeOfDay >= ONE_DAY) {
timeOfDay -= ONE_DAY;
++fixedDate;
} else {
while (timeOfDay < 0) {
timeOfDay += ONE_DAY;
--fixedDate;
}
}
fixedDate += EPOCH_OFFSET;
int era = CE;
int year;
if (fixedDate >= gregorianCutoverDate) {
// Handle Gregorian dates.
assert cachedFixedDate == Long.MIN_VALUE || gdate.isNormalized()
: "cache control: not normalized";
assert cachedFixedDate == Long.MIN_VALUE ||
gcal.getFixedDate(gdate.getNormalizedYear(),
gdate.getMonth(),
gdate.getDayOfMonth(), gdate)
== cachedFixedDate
: "cache control: inconsictency" +
", cachedFixedDate=" + cachedFixedDate +
", computed=" +
gcal.getFixedDate(gdate.getNormalizedYear(),
gdate.getMonth(),
gdate.getDayOfMonth(),
gdate) +
", date=" + gdate;
// See if we can use gdate to avoid date calculation.
if (fixedDate != cachedFixedDate) {
gcal.getCalendarDateFromFixedDate(gdate, fixedDate);
cachedFixedDate = fixedDate;
}
year = gdate.getYear();
if (year <= 0) {
year = 1 - year;
era = BCE;
}
calsys = gcal;
cdate = gdate;
assert cdate.getDayOfWeek() > 0 : "dow="+cdate.getDayOfWeek()+", date="+cdate;
} else {
// Handle Julian calendar dates.
calsys = getJulianCalendarSystem();
cdate = (BaseCalendar.Date) jcal.newCalendarDate(getZone());
jcal.getCalendarDateFromFixedDate(cdate, fixedDate);
Era e = cdate.getEra();
if (e == jeras[0]) {
era = BCE;
}
year = cdate.getYear();
}
// Always set the ERA and YEAR values.
internalSet(ERA, era);
internalSet(YEAR, year);
int mask = fieldMask | (ERA_MASK|YEAR_MASK);
int month = cdate.getMonth() - 1; // 0-based
int dayOfMonth = cdate.getDayOfMonth();
// Set the basic date fields.
if ((fieldMask & (MONTH_MASK|DAY_OF_MONTH_MASK|DAY_OF_WEEK_MASK))
!= 0) {
internalSet(MONTH, month);
internalSet(DAY_OF_MONTH, dayOfMonth);
internalSet(DAY_OF_WEEK, cdate.getDayOfWeek());
mask |= MONTH_MASK|DAY_OF_MONTH_MASK|DAY_OF_WEEK_MASK;
}
if ((fieldMask & (HOUR_OF_DAY_MASK|AM_PM_MASK|HOUR_MASK
|MINUTE_MASK|SECOND_MASK|MILLISECOND_MASK)) != 0) {
if (timeOfDay != 0) {
int hours = timeOfDay / ONE_HOUR;
internalSet(HOUR_OF_DAY, hours);
internalSet(AM_PM, hours / 12); // Assume AM == 0
internalSet(HOUR, hours % 12);
int r = timeOfDay % ONE_HOUR;
internalSet(MINUTE, r / ONE_MINUTE);
r %= ONE_MINUTE;
internalSet(SECOND, r / ONE_SECOND);
internalSet(MILLISECOND, r % ONE_SECOND);
} else {
internalSet(HOUR_OF_DAY, 0);
internalSet(AM_PM, AM);
internalSet(HOUR, 0);
internalSet(MINUTE, 0);
internalSet(SECOND, 0);
internalSet(MILLISECOND, 0);
}
mask |= (HOUR_OF_DAY_MASK|AM_PM_MASK|HOUR_MASK
|MINUTE_MASK|SECOND_MASK|MILLISECOND_MASK);
}
if ((fieldMask & (ZONE_OFFSET_MASK|DST_OFFSET_MASK)) != 0) {
internalSet(ZONE_OFFSET, zoneOffsets[0]);
internalSet(DST_OFFSET, zoneOffsets[1]);
mask |= (ZONE_OFFSET_MASK|DST_OFFSET_MASK);
}
if ((fieldMask & (DAY_OF_YEAR_MASK|WEEK_OF_YEAR_MASK|WEEK_OF_MONTH_MASK|DAY_OF_WEEK_IN_MONTH_MASK)) != 0) {
int normalizedYear = cdate.getNormalizedYear();
long fixedDateJan1 = calsys.getFixedDate(normalizedYear, 1, 1, cdate);
int dayOfYear = (int)(fixedDate - fixedDateJan1) + 1;
long fixedDateMonth1 = fixedDate - dayOfMonth + 1;
int cutoverGap = 0;
int cutoverYear = (calsys == gcal) ? gregorianCutoverYear : gregorianCutoverYearJulian;
int relativeDayOfMonth = dayOfMonth - 1;
// If we are in the cutover year, we need some special handling.
if (normalizedYear == cutoverYear) {
// Need to take care of the "missing" days.
if (gregorianCutoverYearJulian <= gregorianCutoverYear) {
// We need to find out where we are. The cutover
// gap could even be more than one year. (One
// year difference in ~48667 years.)
fixedDateJan1 = getFixedDateJan1(cdate, fixedDate);
if (fixedDate >= gregorianCutoverDate) {
fixedDateMonth1 = getFixedDateMonth1(cdate, fixedDate);
}
}
int realDayOfYear = (int)(fixedDate - fixedDateJan1) + 1;
cutoverGap = dayOfYear - realDayOfYear;
dayOfYear = realDayOfYear;
relativeDayOfMonth = (int)(fixedDate - fixedDateMonth1);
}
internalSet(DAY_OF_YEAR, dayOfYear);
internalSet(DAY_OF_WEEK_IN_MONTH, relativeDayOfMonth / 7 + 1);
int weekOfYear = getWeekNumber(fixedDateJan1, fixedDate);
// The spec is to calculate WEEK_OF_YEAR in the
// ISO8601-style. This creates problems, though.
if (weekOfYear == 0) {
// If the date belongs to the last week of the
// previous year, use the week number of "12/31" of
// the "previous" year. Again, if the previous year is
// the Gregorian cutover year, we need to take care of
// it. Usually the previous day of January 1 is
// December 31, which is not always true in
// GregorianCalendar.
long fixedDec31 = fixedDateJan1 - 1;
long prevJan1 = fixedDateJan1 - 365;
if (normalizedYear > (cutoverYear + 1)) {
if (CalendarUtils.isGregorianLeapYear(normalizedYear - 1)) {
--prevJan1;
}
} else if (normalizedYear <= gregorianCutoverYearJulian) {
if (CalendarUtils.isJulianLeapYear(normalizedYear - 1)) {
--prevJan1;
}
} else {
BaseCalendar calForJan1 = calsys;
//int prevYear = normalizedYear - 1;
int prevYear = getCalendarDate(fixedDec31).getNormalizedYear();
if (prevYear == gregorianCutoverYear) {
calForJan1 = getCutoverCalendarSystem();
if (calForJan1 == jcal) {
prevJan1 = calForJan1.getFixedDate(prevYear,
BaseCalendar.JANUARY,
1,
null);
} else {
prevJan1 = gregorianCutoverDate;
calForJan1 = gcal;
}
} else if (prevYear <= gregorianCutoverYearJulian) {
calForJan1 = getJulianCalendarSystem();
prevJan1 = calForJan1.getFixedDate(prevYear,
BaseCalendar.JANUARY,
1,
null);
}
}
weekOfYear = getWeekNumber(prevJan1, fixedDec31);
} else {
if (normalizedYear > gregorianCutoverYear ||
normalizedYear < (gregorianCutoverYearJulian - 1)) {
// Regular years
if (weekOfYear >= 52) {
long nextJan1 = fixedDateJan1 + 365;
if (cdate.isLeapYear()) {
nextJan1++;
}
long nextJan1st = BaseCalendar.getDayOfWeekDateOnOrBefore(nextJan1 + 6,
getFirstDayOfWeek());
int ndays = (int)(nextJan1st - nextJan1);
if (ndays >= getMinimalDaysInFirstWeek() && fixedDate >= (nextJan1st - 7)) {
// The first days forms a week in which the date is included.
weekOfYear = 1;
}
}
} else {
BaseCalendar calForJan1 = calsys;
int nextYear = normalizedYear + 1;
if (nextYear == (gregorianCutoverYearJulian + 1) &&
nextYear < gregorianCutoverYear) {
// In case the gap is more than one year.
nextYear = gregorianCutoverYear;
}
if (nextYear == gregorianCutoverYear) {
calForJan1 = getCutoverCalendarSystem();
}
long nextJan1;
if (nextYear > gregorianCutoverYear
|| gregorianCutoverYearJulian == gregorianCutoverYear
|| nextYear == gregorianCutoverYearJulian) {
nextJan1 = calForJan1.getFixedDate(nextYear,
BaseCalendar.JANUARY,
1,
null);
} else {
nextJan1 = gregorianCutoverDate;
calForJan1 = gcal;
}
long nextJan1st = BaseCalendar.getDayOfWeekDateOnOrBefore(nextJan1 + 6,
getFirstDayOfWeek());
int ndays = (int)(nextJan1st - nextJan1);
if (ndays >= getMinimalDaysInFirstWeek() && fixedDate >= (nextJan1st - 7)) {
// The first days forms a week in which the date is included.
weekOfYear = 1;
}
}
}
internalSet(WEEK_OF_YEAR, weekOfYear);
internalSet(WEEK_OF_MONTH, getWeekNumber(fixedDateMonth1, fixedDate));
mask |= (DAY_OF_YEAR_MASK|WEEK_OF_YEAR_MASK|WEEK_OF_MONTH_MASK|DAY_OF_WEEK_IN_MONTH_MASK);
}
return mask;
}
/**
* Returns the number of weeks in a period between fixedDay1 and
* fixedDate. The getFirstDayOfWeek-getMinimalDaysInFirstWeek rule
* is applied to calculate the number of weeks.
*
* @param fixedDay1 the fixed date of the first day of the period
* @param fixedDate the fixed date of the last day of the period
* @return the number of weeks of the given period
*/
private int getWeekNumber(long fixedDay1, long fixedDate) {
// We can always use `gcal' since Julian and Gregorian are the
// same thing for this calculation.
long fixedDay1st = Gregorian.getDayOfWeekDateOnOrBefore(fixedDay1 + 6,
getFirstDayOfWeek());
int ndays = (int)(fixedDay1st - fixedDay1);
assert ndays <= 7;
if (ndays >= getMinimalDaysInFirstWeek()) {
fixedDay1st -= 7;
}
int normalizedDayOfPeriod = (int)(fixedDate - fixedDay1st);
if (normalizedDayOfPeriod >= 0) {
return normalizedDayOfPeriod / 7 + 1;
}
return CalendarUtils.floorDivide(normalizedDayOfPeriod, 7) + 1;
}
/**
* Converts calendar field values to the time value (millisecond
* offset from the Epoch).
*
* @throws IllegalArgumentException if any calendar fields are invalid.
*/
@Override
protected void computeTime() {
// In non-lenient mode, perform brief checking of calendar
// fields which have been set externally. Through this
// checking, the field values are stored in originalFields[]
// to see if any of them are normalized later.
if (!isLenient()) {
if (originalFields == null) {
originalFields = new int[FIELD_COUNT];
}
for (int field = 0; field < FIELD_COUNT; field++) {
int value = internalGet(field);
if (isExternallySet(field)) {
// Quick validation for any out of range values
if (value < getMinimum(field) || value > getMaximum(field)) {
throw new IllegalArgumentException(getFieldName(field));
}
}
originalFields[field] = value;
}
}
// Let the super class determine which calendar fields to be
// used to calculate the time.
int fieldMask = selectFields();
// The year defaults to the epoch start. We don't check
// fieldMask for YEAR because YEAR is a mandatory field to
// determine the date.
int year = isSet(YEAR) ? internalGet(YEAR) : EPOCH_YEAR;
int era = internalGetEra();
if (era == BCE) {
year = 1 - year;
} else if (era != CE) {
// Even in lenient mode we disallow ERA values other than CE & BCE.
// (The same normalization rule as add()/roll() could be
// applied here in lenient mode. But this checking is kept
// unchanged for compatibility as of 1.5.)
throw new IllegalArgumentException("Invalid era");
}
// If year is 0 or negative, we need to set the ERA value later.
if (year <= 0 && !isSet(ERA)) {
fieldMask |= ERA_MASK;
setFieldsComputed(ERA_MASK);
}
// Calculate the time of day. We rely on the convention that
// an UNSET field has 0.
long timeOfDay = 0;
if (isFieldSet(fieldMask, HOUR_OF_DAY)) {
timeOfDay += (long) internalGet(HOUR_OF_DAY);
} else {
timeOfDay += internalGet(HOUR);
// The default value of AM_PM is 0 which designates AM.
if (isFieldSet(fieldMask, AM_PM)) {
timeOfDay += 12 * internalGet(AM_PM);
}
}
timeOfDay *= 60;
timeOfDay += internalGet(MINUTE);
timeOfDay *= 60;
timeOfDay += internalGet(SECOND);
timeOfDay *= 1000;
timeOfDay += internalGet(MILLISECOND);
// Convert the time of day to the number of days and the
// millisecond offset from midnight.
long fixedDate = timeOfDay / ONE_DAY;
timeOfDay %= ONE_DAY;
while (timeOfDay < 0) {
timeOfDay += ONE_DAY;
--fixedDate;
}
// Calculate the fixed date since January 1, 1 (Gregorian).
calculateFixedDate: {
long gfd, jfd;
if (year > gregorianCutoverYear && year > gregorianCutoverYearJulian) {
gfd = fixedDate + getFixedDate(gcal, year, fieldMask);
if (gfd >= gregorianCutoverDate) {
fixedDate = gfd;
break calculateFixedDate;
}
jfd = fixedDate + getFixedDate(getJulianCalendarSystem(), year, fieldMask);
} else if (year < gregorianCutoverYear && year < gregorianCutoverYearJulian) {
jfd = fixedDate + getFixedDate(getJulianCalendarSystem(), year, fieldMask);
if (jfd < gregorianCutoverDate) {
fixedDate = jfd;
break calculateFixedDate;
}
gfd = jfd;
} else {
jfd = fixedDate + getFixedDate(getJulianCalendarSystem(), year, fieldMask);
gfd = fixedDate + getFixedDate(gcal, year, fieldMask);
}
// Now we have to determine which calendar date it is.
// If the date is relative from the beginning of the year
// in the Julian calendar, then use jfd;
if (isFieldSet(fieldMask, DAY_OF_YEAR) || isFieldSet(fieldMask, WEEK_OF_YEAR)) {
if (gregorianCutoverYear == gregorianCutoverYearJulian) {
fixedDate = jfd;
break calculateFixedDate;
} else if (year == gregorianCutoverYear) {
fixedDate = gfd;
break calculateFixedDate;
}
}
if (gfd >= gregorianCutoverDate) {
if (jfd >= gregorianCutoverDate) {
fixedDate = gfd;
} else {
// The date is in an "overlapping" period. No way
// to disambiguate it. Determine it using the
// previous date calculation.
if (calsys == gcal || calsys == null) {
fixedDate = gfd;
} else {
fixedDate = jfd;
}
}
} else {
if (jfd < gregorianCutoverDate) {
fixedDate = jfd;
} else {
// The date is in a "missing" period.
if (!isLenient()) {
throw new IllegalArgumentException("the specified date doesn't exist");
}
// Take the Julian date for compatibility, which
// will produce a Gregorian date.
fixedDate = jfd;
}
}
}
// millis represents local wall-clock time in milliseconds.
long millis = (fixedDate - EPOCH_OFFSET) * ONE_DAY + timeOfDay;
// 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.
TimeZone zone = getZone();
// BEGIN Android-changed: time zone related calculation via helper methods.
int tzMask = fieldMask & (ZONE_OFFSET_MASK|DST_OFFSET_MASK);
millis = adjustForZoneAndDaylightSavingsTime(tzMask, millis, zone);
// END Android-changed: time zone related calculation via helper methods.
// Set this calendar's time in milliseconds
time = millis;
int mask = computeFields(fieldMask | getSetStateFields(), tzMask);
if (!isLenient()) {
for (int field = 0; field < FIELD_COUNT; field++) {
if (!isExternallySet(field)) {
continue;
}
if (originalFields[field] != internalGet(field)) {
String s = originalFields[field] + " -> " + internalGet(field);
// Restore the original field values
System.arraycopy(originalFields, 0, fields, 0, fields.length);
throw new IllegalArgumentException(getFieldName(field) + ": " + s);
}
}
}
setFieldsNormalized(mask);
}
// BEGIN Android-added: helper methods for time zone related calculation.
/**
* Calculates the time in milliseconds that this calendar represents using the UTC time,
* timezone information (specifically Daylight Savings Time (DST) rules, if any) and knowledge
* of what fields were explicitly set on the calendar.
*
* A time is represented as the number of milliseconds since
* 1st January 1970 00:00:00.000 UTC.
*
* This uses the terms {@link SimpleTimeZone#STANDARD_TIME standard time},
* {@link SimpleTimeZone#WALL_TIME} wall time} and {@link SimpleTimeZone#UTC_TIME UTC time} as
* used in {@link SimpleTimeZone}. Specifically:
*
* The {@code utcTimeInMillis} value supplied was calculated as if the fields represented
* a standard time in the {@code UTC} time zone. It is the value that would be returned by
* {@link #getTimeInMillis()} when called on this calendar if it was in UTC time zone. e.g. If
* the calendar was set to say 2014 March 19th 13:27.53 -08:00 then the value of
* {@code utcTimeInMillis} would be the value of {@link #getTimeInMillis()} when called on a
* calendar set to 2014 March 19th 13:27.53 -00:00, note the time zone offset is set to
* 0.
*
* To adjust from a UTC time in millis to the standard time in millis we must
* subtract the offset from UTC. e.g. given an offset of UTC-08:00, to convert
* "14:00 UTC" to "14:00 UTC-08:00" we must subtract -08:00 (i.e. add 8 hours). Another way to
* think about it is that 8 hours has to elapse after 14:00 UTC before it is 14:00 UTC-08:00.
*
* As the zone offset can depend on the time and we cannot calculate the time properly until
* we know the time there is a bit of a catch-22. So, what this does is use the
* {@link TimeZone#getRawOffset() raw offset} to calculate a ballpark standard time and then
* uses that value to retrieve the appropriate zone and DST offsets from the time zone. They
* are then used to make the final wall time calculation.
*
* The DST offset will need clearing if the standard time is not a valid wall clock. See
* {@link #adjustDstOffsetForInvalidWallClock(long, TimeZone, int)} for more information.
*
* @param tzMask the set of time zone related fields, i.e. {@link #ZONE_OFFSET_MASK} and
* {@link #DST_OFFSET_MASK}
* @param utcTimeInMillis the time in millis, calculated assuming the time zone was GMT.
* @param zone the actual time zone.
* @return the UTC time in millis after adjusting for zone and DST offset.
*/
private long adjustForZoneAndDaylightSavingsTime(
int tzMask, long utcTimeInMillis, TimeZone zone) {
// The following don't actually need to be initialized because they are always set before
// they are used but the compiler cannot detect that.
int zoneOffset = 0;
int dstOffset = 0;
// If either of the ZONE_OFFSET or DST_OFFSET fields are not set then get the information
// from the TimeZone.
if (tzMask != (ZONE_OFFSET_MASK|DST_OFFSET_MASK)) {
if (zoneOffsets == null) {
zoneOffsets = new int[2];
}
int gmtOffset = isFieldSet(tzMask, ZONE_OFFSET) ?
internalGet(ZONE_OFFSET) : zone.getRawOffset();
// Calculate the standard time (no DST) in the supplied zone. This is a ballpark figure
// and not used in the final calculation as the offset used here may not be the same as
// the actual offset the time zone requires be used for this time. This is to handle
// situations like Honolulu, where its raw offset changed from GMT-10:30 to GMT-10:00
// in 1947. The TimeZone always uses a raw offset of -10:00 but will return -10:30
// for dates before the change over.
long standardTimeInZone = utcTimeInMillis - gmtOffset;
// Retrieve the correct zone and DST offsets from the time zone.
if (zone instanceof ZoneInfo) {
// Android-changed: libcore ZoneInfo uses different method to get offsets.
ZoneInfo zoneInfo = (ZoneInfo) zone;
zoneInfo.getOffsetsByUtcTime(standardTimeInZone, zoneOffsets);
} else {
zone.getOffsets(standardTimeInZone, zoneOffsets);
}
zoneOffset = zoneOffsets[0];
dstOffset = zoneOffsets[1];
// If necessary adjust the DST offset to handle an invalid wall clock sensibly.
dstOffset = adjustDstOffsetForInvalidWallClock(standardTimeInZone, zone, dstOffset);
}
// If either ZONE_OFFSET of DST_OFFSET fields are set then get the information from the
// fields, potentially overriding information from the TimeZone.
if (tzMask != 0) {
if (isFieldSet(tzMask, ZONE_OFFSET)) {
zoneOffset = internalGet(ZONE_OFFSET);
}
if (isFieldSet(tzMask, DST_OFFSET)) {
dstOffset = internalGet(DST_OFFSET);
}
}
// Adjust the time zone offset values to get the UTC time.
long standardTimeInZone = utcTimeInMillis - zoneOffset;
return standardTimeInZone - dstOffset;
}
/**
* If the supplied millis is in daylight savings time (DST) and is the result of an invalid
* wall clock then adjust the DST offset to ensure sensible behavior.
*
* When transitioning into DST, i.e. when the clocks spring forward (usually by one hour)
* there is a wall clock period that is invalid, it literally doesn't exist. e.g. If clocks
* go forward one hour at 02:00 on 9th March 2014 (standard time) then the wall time of
* 02:00-02:59:59.999 is not a valid. The wall clock jumps straight from 01:59:59.999 to
* 03:00. The following table shows the relationship between the time in millis, the standard
* time and the wall time at the point of transitioning into DST. As can be seen there is no
* 02:00 in the wall time.
*
* The calendar fields represent wall time. If the user sets the fields on the calendar so
* that it is in that invalid period then this code attempts to do something sensible. It
* treats 02:MM:SS.SSS as if it is {@code 01:MM:SS.SSS + 1 hour}. That makes sense from both
* the input calendar fields perspective and from the time in millis perspective. Of course the
* result of that is that when the time is formatted in that time zone that the time is
* actually 03:MM:SS.SSS.
*
* The way that works is as follows. First the standard time is calculated and the DST
* offset is determined. Then if the time is in DST (the DST offset is not 0) but it was not in
* DST an hour earlier (or however long the DST offset is) then it must be in that invalid
* period, in which case set the DST offset to 0. That is then subtracted from the time in
* millis to produce the correct result. The following diagram illustrates the process.
*
*
* Since this object supports a Julian-Gregorian cutover date and
* {@code ZonedDateTime} does not, it is possible that the resulting year,
* month and day will have different values. The result will represent the
* correct date in the ISO calendar system, which will also be the same value
* for Modified Julian Days.
*
* @return a zoned date-time representing the same point on the time-line
* as this gregorian calendar
* @since 1.8
*/
public ZonedDateTime toZonedDateTime() {
return ZonedDateTime.ofInstant(Instant.ofEpochMilli(getTimeInMillis()),
getTimeZone().toZoneId());
}
/**
* Obtains an instance of {@code GregorianCalendar} with the default locale
* from a {@code ZonedDateTime} object.
*
* Since {@code ZonedDateTime} does not support a Julian-Gregorian cutover
* date and uses ISO calendar system, the return GregorianCalendar is a pure
* Gregorian calendar and uses ISO 8601 standard for week definitions,
* which has {@code MONDAY} as the {@link Calendar#getFirstDayOfWeek()
* FirstDayOfWeek} and {@code 4} as the value of the
* {@link Calendar#getMinimalDaysInFirstWeek() MinimalDaysInFirstWeek}.
*
* {@code ZoneDateTime} can store points on the time-line further in the
* future and further in the past than {@code GregorianCalendar}. In this
* scenario, this method will throw an {@code IllegalArgumentException}
* exception.
*
* @param zdt the zoned date-time object to convert
* @return the gregorian calendar representing the same point on the
* time-line as the zoned date-time provided
* @throws NullPointerException if {@code zdt} is null
* @throws IllegalArgumentException if the zoned date-time is too
* large to represent as a {@code GregorianCalendar}
* @since 1.8
*/
public static GregorianCalendar from(ZonedDateTime zdt) {
GregorianCalendar cal = new GregorianCalendar(TimeZone.getTimeZone(zdt.getZone()));
cal.setGregorianChange(new Date(Long.MIN_VALUE));
cal.setFirstDayOfWeek(MONDAY);
cal.setMinimalDaysInFirstWeek(4);
try {
cal.setTimeInMillis(Math.addExact(Math.multiplyExact(zdt.toEpochSecond(), 1000),
zdt.get(ChronoField.MILLI_OF_SECOND)));
} catch (ArithmeticException ex) {
throw new IllegalArgumentException(ex);
}
return cal;
}
}
*
*
*
* Time In Millis - ...... x+1h ..... x+2h ..... x+3h
* Standard Time - ...... 01:00 ..... 02:00 ..... 03:00 .....
* Wall Time - ...... 01:00 ..... 03:00 ..... 04:00 .....
* ^
* 02:00 missing
*
*
*
* Wall Time - ...... 01:00 ..... 02:00 ..... 03:00 ..... 04:00 .....
* Time In Millis - ...... x+1h ..... x+2h ..... x+2h ..... x+3h .....
*
*
*
* Standard Time - ...... 01:00 ..... 02:00 ..... 03:00 ..... 04:00 .....
* Time In Millis - ...... x+1h ..... x+2h ..... x+3h ..... x+4h .....
* DST Offset - ...... 0h ..... 1h ..... 1h ..... 1h .....
* Adjusted DST - ...... 0h ..... 0h ..... 1h ..... 1h .....
* Adjusted Time - ...... x+1h ..... x+2h ..... x+2h ..... x+3h .....
*
*
* @return the adjusted DST offset.
*/
private int adjustDstOffsetForInvalidWallClock(
long standardTimeInZone, TimeZone zone, int dstOffset) {
if (dstOffset != 0) {
// If applying the DST offset produces a time that is outside DST then it must be
// an invalid wall clock so clear the DST offset to avoid that happening.
if (!zone.inDaylightTime(new Date(standardTimeInZone - dstOffset))) {
dstOffset = 0;
}
}
return dstOffset;
}
// END Android-added: helper methods for time zone related calculation.
/**
* Computes the fixed date under either the Gregorian or the
* Julian calendar, using the given year and the specified calendar fields.
*
* @param cal the CalendarSystem to be used for the date calculation
* @param year the normalized year number, with 0 indicating the
* year 1 BCE, -1 indicating 2 BCE, etc.
* @param fieldMask the calendar fields to be used for the date calculation
* @return the fixed date
* @see Calendar#selectFields
*/
private long getFixedDate(BaseCalendar cal, int year, int fieldMask) {
int month = JANUARY;
if (isFieldSet(fieldMask, MONTH)) {
// No need to check if MONTH has been set (no isSet(MONTH)
// call) since its unset value happens to be JANUARY (0).
month = internalGet(MONTH);
// If the month is out of range, adjust it into range
if (month > DECEMBER) {
year += month / 12;
month %= 12;
} else if (month < JANUARY) {
int[] rem = new int[1];
year += CalendarUtils.floorDivide(month, 12, rem);
month = rem[0];
}
}
// Get the fixed date since Jan 1, 1 (Gregorian). We are on
// the first day of either `month' or January in 'year'.
long fixedDate = cal.getFixedDate(year, month + 1, 1,
cal == gcal ? gdate : null);
if (isFieldSet(fieldMask, MONTH)) {
// Month-based calculations
if (isFieldSet(fieldMask, DAY_OF_MONTH)) {
// We are on the first day of the month. Just add the
// offset if DAY_OF_MONTH is set. If the isSet call
// returns false, that means DAY_OF_MONTH has been
// selected just because of the selected
// combination. We don't need to add any since the
// default value is the 1st.
if (isSet(DAY_OF_MONTH)) {
// To avoid underflow with DAY_OF_MONTH-1, add
// DAY_OF_MONTH, then subtract 1.
fixedDate += internalGet(DAY_OF_MONTH);
fixedDate--;
}
} else {
if (isFieldSet(fieldMask, WEEK_OF_MONTH)) {
long firstDayOfWeek = BaseCalendar.getDayOfWeekDateOnOrBefore(fixedDate + 6,
getFirstDayOfWeek());
// If we have enough days in the first week, then
// move to the previous week.
if ((firstDayOfWeek - fixedDate) >= getMinimalDaysInFirstWeek()) {
firstDayOfWeek -= 7;
}
if (isFieldSet(fieldMask, DAY_OF_WEEK)) {
firstDayOfWeek = BaseCalendar.getDayOfWeekDateOnOrBefore(firstDayOfWeek + 6,
internalGet(DAY_OF_WEEK));
}
// In lenient mode, we treat days of the previous
// months as a part of the specified
// WEEK_OF_MONTH. See 4633646.
fixedDate = firstDayOfWeek + 7 * (internalGet(WEEK_OF_MONTH) - 1);
} else {
int dayOfWeek;
if (isFieldSet(fieldMask, DAY_OF_WEEK)) {
dayOfWeek = internalGet(DAY_OF_WEEK);
} else {
dayOfWeek = getFirstDayOfWeek();
}
// We are basing this on the day-of-week-in-month. The only
// trickiness occurs if the day-of-week-in-month is
// negative.
int dowim;
if (isFieldSet(fieldMask, DAY_OF_WEEK_IN_MONTH)) {
dowim = internalGet(DAY_OF_WEEK_IN_MONTH);
} else {
dowim = 1;
}
if (dowim >= 0) {
fixedDate = BaseCalendar.getDayOfWeekDateOnOrBefore(fixedDate + (7 * dowim) - 1,
dayOfWeek);
} else {
// Go to the first day of the next week of
// the specified week boundary.
int lastDate = monthLength(month, year) + (7 * (dowim + 1));
// Then, get the day of week date on or before the last date.
fixedDate = BaseCalendar.getDayOfWeekDateOnOrBefore(fixedDate + lastDate - 1,
dayOfWeek);
}
}
}
} else {
if (year == gregorianCutoverYear && cal == gcal
&& fixedDate < gregorianCutoverDate
&& gregorianCutoverYear != gregorianCutoverYearJulian) {
// January 1 of the year doesn't exist. Use
// gregorianCutoverDate as the first day of the
// year.
fixedDate = gregorianCutoverDate;
}
// We are on the first day of the year.
if (isFieldSet(fieldMask, DAY_OF_YEAR)) {
// Add the offset, then subtract 1. (Make sure to avoid underflow.)
fixedDate += internalGet(DAY_OF_YEAR);
fixedDate--;
} else {
long firstDayOfWeek = BaseCalendar.getDayOfWeekDateOnOrBefore(fixedDate + 6,
getFirstDayOfWeek());
// If we have enough days in the first week, then move
// to the previous week.
if ((firstDayOfWeek - fixedDate) >= getMinimalDaysInFirstWeek()) {
firstDayOfWeek -= 7;
}
if (isFieldSet(fieldMask, DAY_OF_WEEK)) {
int dayOfWeek = internalGet(DAY_OF_WEEK);
if (dayOfWeek != getFirstDayOfWeek()) {
firstDayOfWeek = BaseCalendar.getDayOfWeekDateOnOrBefore(firstDayOfWeek + 6,
dayOfWeek);
}
}
fixedDate = firstDayOfWeek + 7 * ((long)internalGet(WEEK_OF_YEAR) - 1);
}
}
return fixedDate;
}
/**
* Returns this object if it's normalized (all fields and time are
* in sync). Otherwise, a cloned object is returned after calling
* complete() in lenient mode.
*/
private GregorianCalendar getNormalizedCalendar() {
GregorianCalendar gc;
if (isFullyNormalized()) {
gc = this;
} else {
// Create a clone and normalize the calendar fields
gc = (GregorianCalendar) this.clone();
gc.setLenient(true);
gc.complete();
}
return gc;
}
/**
* Returns the Julian calendar system instance (singleton). 'jcal'
* and 'jeras' are set upon the return.
*/
private static synchronized BaseCalendar getJulianCalendarSystem() {
if (jcal == null) {
jcal = (JulianCalendar) CalendarSystem.forName("julian");
jeras = jcal.getEras();
}
return jcal;
}
/**
* Returns the calendar system for dates before the cutover date
* in the cutover year. If the cutover date is January 1, the
* method returns Gregorian. Otherwise, Julian.
*/
private BaseCalendar getCutoverCalendarSystem() {
if (gregorianCutoverYearJulian < gregorianCutoverYear) {
return gcal;
}
return getJulianCalendarSystem();
}
/**
* Determines if the specified year (normalized) is the Gregorian
* cutover year. This object must have been normalized.
*/
private boolean isCutoverYear(int normalizedYear) {
int cutoverYear = (calsys == gcal) ? gregorianCutoverYear : gregorianCutoverYearJulian;
return normalizedYear == cutoverYear;
}
/**
* Returns the fixed date of the first day of the year (usually
* January 1) before the specified date.
*
* @param date the date for which the first day of the year is
* calculated. The date has to be in the cut-over year (Gregorian
* or Julian).
* @param fixedDate the fixed date representation of the date
*/
private long getFixedDateJan1(BaseCalendar.Date date, long fixedDate) {
assert date.getNormalizedYear() == gregorianCutoverYear ||
date.getNormalizedYear() == gregorianCutoverYearJulian;
if (gregorianCutoverYear != gregorianCutoverYearJulian) {
if (fixedDate >= gregorianCutoverDate) {
// Dates before the cutover date don't exist
// in the same (Gregorian) year. So, no
// January 1 exists in the year. Use the
// cutover date as the first day of the year.
return gregorianCutoverDate;
}
}
// January 1 of the normalized year should exist.
BaseCalendar juliancal = getJulianCalendarSystem();
return juliancal.getFixedDate(date.getNormalizedYear(), BaseCalendar.JANUARY, 1, null);
}
/**
* Returns the fixed date of the first date of the month (usually
* the 1st of the month) before the specified date.
*
* @param date the date for which the first day of the month is
* calculated. The date has to be in the cut-over year (Gregorian
* or Julian).
* @param fixedDate the fixed date representation of the date
*/
private long getFixedDateMonth1(BaseCalendar.Date date, long fixedDate) {
assert date.getNormalizedYear() == gregorianCutoverYear ||
date.getNormalizedYear() == gregorianCutoverYearJulian;
BaseCalendar.Date gCutover = getGregorianCutoverDate();
if (gCutover.getMonth() == BaseCalendar.JANUARY
&& gCutover.getDayOfMonth() == 1) {
// The cutover happened on January 1.
return fixedDate - date.getDayOfMonth() + 1;
}
long fixedDateMonth1;
// The cutover happened sometime during the year.
if (date.getMonth() == gCutover.getMonth()) {
// The cutover happened in the month.
BaseCalendar.Date jLastDate = getLastJulianDate();
if (gregorianCutoverYear == gregorianCutoverYearJulian
&& gCutover.getMonth() == jLastDate.getMonth()) {
// The "gap" fits in the same month.
fixedDateMonth1 = jcal.getFixedDate(date.getNormalizedYear(),
date.getMonth(),
1,
null);
} else {
// Use the cutover date as the first day of the month.
fixedDateMonth1 = gregorianCutoverDate;
}
} else {
// The cutover happened before the month.
fixedDateMonth1 = fixedDate - date.getDayOfMonth() + 1;
}
return fixedDateMonth1;
}
/**
* Returns a CalendarDate produced from the specified fixed date.
*
* @param fd the fixed date
*/
private BaseCalendar.Date getCalendarDate(long fd) {
BaseCalendar cal = (fd >= gregorianCutoverDate) ? gcal : getJulianCalendarSystem();
BaseCalendar.Date d = (BaseCalendar.Date) cal.newCalendarDate(TimeZone.NO_TIMEZONE);
cal.getCalendarDateFromFixedDate(d, fd);
return d;
}
/**
* Returns the Gregorian cutover date as a BaseCalendar.Date. The
* date is a Gregorian date.
*/
private BaseCalendar.Date getGregorianCutoverDate() {
return getCalendarDate(gregorianCutoverDate);
}
/**
* Returns the day before the Gregorian cutover date as a
* BaseCalendar.Date. The date is a Julian date.
*/
private BaseCalendar.Date getLastJulianDate() {
return getCalendarDate(gregorianCutoverDate - 1);
}
/**
* Returns the length of the specified month in the specified
* year. The year number must be normalized.
*
* @see #isLeapYear(int)
*/
private int monthLength(int month, int year) {
return isLeapYear(year) ? LEAP_MONTH_LENGTH[month] : MONTH_LENGTH[month];
}
/**
* Returns the length of the specified month in the year provided
* by internalGet(YEAR).
*
* @see #isLeapYear(int)
*/
private int monthLength(int month) {
int year = internalGet(YEAR);
if (internalGetEra() == BCE) {
year = 1 - year;
}
return monthLength(month, year);
}
private int actualMonthLength() {
int year = cdate.getNormalizedYear();
if (year != gregorianCutoverYear && year != gregorianCutoverYearJulian) {
return calsys.getMonthLength(cdate);
}
BaseCalendar.Date date = (BaseCalendar.Date) cdate.clone();
long fd = calsys.getFixedDate(date);
long month1 = getFixedDateMonth1(date, fd);
long next1 = month1 + calsys.getMonthLength(date);
if (next1 < gregorianCutoverDate) {
return (int)(next1 - month1);
}
if (cdate != gdate) {
date = (BaseCalendar.Date) gcal.newCalendarDate(TimeZone.NO_TIMEZONE);
}
gcal.getCalendarDateFromFixedDate(date, next1);
next1 = getFixedDateMonth1(date, next1);
return (int)(next1 - month1);
}
/**
* Returns the length (in days) of the specified year. The year
* must be normalized.
*/
private int yearLength(int year) {
return isLeapYear(year) ? 366 : 365;
}
/**
* Returns the length (in days) of the year provided by
* internalGet(YEAR).
*/
private int yearLength() {
int year = internalGet(YEAR);
if (internalGetEra() == BCE) {
year = 1 - year;
}
return yearLength(year);
}
/**
* 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.
*/
private void pinDayOfMonth() {
int year = internalGet(YEAR);
int monthLen;
if (year > gregorianCutoverYear || year < gregorianCutoverYearJulian) {
monthLen = monthLength(internalGet(MONTH));
} else {
GregorianCalendar gc = getNormalizedCalendar();
monthLen = gc.getActualMaximum(DAY_OF_MONTH);
}
int dom = internalGet(DAY_OF_MONTH);
if (dom > monthLen) {
set(DAY_OF_MONTH, monthLen);
}
}
/**
* Returns the fixed date value of this object. The time value and
* calendar fields must be in synch.
*/
private long getCurrentFixedDate() {
return (calsys == gcal) ? cachedFixedDate : calsys.getFixedDate(cdate);
}
/**
* Returns the new value after 'roll'ing the specified value and amount.
*/
private static int getRolledValue(int value, int amount, int min, int max) {
assert value >= min && value <= max;
int range = max - min + 1;
amount %= range;
int n = value + amount;
if (n > max) {
n -= range;
} else if (n < min) {
n += range;
}
assert n >= min && n <= max;
return n;
}
/**
* Returns the ERA. We need a special method for this because the
* default ERA is CE, but a zero (unset) ERA is BCE.
*/
private int internalGetEra() {
return isSet(ERA) ? internalGet(ERA) : CE;
}
/**
* Updates internal state.
*/
@java.io.Serial
private void readObject(ObjectInputStream stream)
throws IOException, ClassNotFoundException {
stream.defaultReadObject();
if (gdate == null) {
gdate = (BaseCalendar.Date) gcal.newCalendarDate(getZone());
cachedFixedDate = Long.MIN_VALUE;
}
setGregorianChange(gregorianCutover);
}
/**
* Converts this object to a {@code ZonedDateTime} that represents
* the same point on the time-line as this {@code GregorianCalendar}.
*