GregorianCalendar (Java 2 Platform SE 5.0) (original) (raw)
java.util
Class GregorianCalendar
java.lang.Object
java.util.Calendar
java.util.GregorianCalendar
All Implemented Interfaces:
Serializable, Cloneable, Comparable<Calendar>
public class GregorianCalendar
extends Calendar
GregorianCalendar
is a concrete subclass ofCalendar
and provides the standard calendar system used by most of the world.
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 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, 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.
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,GregorianCalendar
may be used for all years to generate meaningful and consistent results. However, dates obtained usingGregorianCalendar
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 WEEK_OF_YEAR
field range from 1 to 53. Week 1 for a year is the earliest seven day period starting ongetFirstDayOfWeek()
that contains at leastgetMinimalDaysInFirstWeek()
days from that year. It thus depends on the values of getMinimalDaysInFirstWeek()
,getFirstDayOfWeek()
, and the day of the week of January 1. Weeks between week 1 of one year and week 1 of the following year are numbered sequentially from 2 to 52 or 53 (as needed).
For example, January 1, 1998 was a Thursday. IfgetFirstDayOfWeek()
is MONDAY
andgetMinimalDaysInFirstWeek()
is 4 (these are the values reflecting ISO 8601 and many national standards), then week 1 of 1998 starts on December 29, 1997, and ends on January 4, 1998. If, however,getFirstDayOfWeek()
is 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.
Values calculated for the 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 leastgetMinimalDaysInFirstWeek()
contiguous days in that month, ending on the day before getFirstDayOfWeek()
. Unlike week 1 of a year, week 1 of a month may be shorter than 7 days, need not start on getFirstDayOfWeek()
, and will not include days of the previous month. Days of a month before week 1 have aWEEK_OF_MONTH
of 0.
For example, if getFirstDayOfWeek()
is SUNDAY
and getMinimalDaysInFirstWeek()
is 4, then the first week of January 1998 is Sunday, January 4 through Saturday, January 10. These days have a WEEK_OF_MONTH
of 1. Thursday, January 1 through Saturday, January 3 have a WEEK_OF_MONTH
of 0. IfgetMinimalDaysInFirstWeek()
is changed to 3, then January 1 through January 3 have a WEEK_OF_MONTH
of 1.
The clear
methods set calendar field(s) undefined. GregorianCalendar
uses the following default value for each calendar field if its value is undefined.
Field | Default Value |
---|---|
ERA | AD |
YEAR | 1970 |
MONTH | JANUARY |
DAY_OF_MONTH | 1 |
DAY_OF_WEEK | the first day of week |
WEEK_OF_MONTH | 0 |
DAY_OF_WEEK_IN_MONTH | 1 |
AM_PM | AM |
HOUR, HOUR_OF_DAY, MINUTE, SECOND, MILLISECOND | 0 |
Default values are not applicable for the fields not listed above.
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 savings 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)/(60601000))); System.out.println("DST_OFFSET: " + (calendar.get(Calendar.DST_OFFSET)/(60601000)));
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)/(60601000))); // in hours System.out.println("DST_OFFSET: " + (calendar.get(Calendar.DST_OFFSET)/(60601000))); // in hours
Since:
JDK1.1
See Also:
Field Summary | |
---|---|
static int | AD Value of the ERA field indicating the common era (Anno Domini), also known as CE. |
static int | BC Value of the ERA field indicating the period before the common era (before Christ), also known as BCE. |
Fields inherited from class java.util.Calendar |
---|
AM, AM_PM, APRIL, areFieldsSet, AUGUST, DATE, DAY_OF_MONTH, DAY_OF_WEEK, DAY_OF_WEEK_IN_MONTH, DAY_OF_YEAR, DECEMBER, DST_OFFSET, ERA, FEBRUARY, FIELD_COUNT, fields, FRIDAY, HOUR, HOUR_OF_DAY, isSet, isTimeSet, JANUARY, JULY, JUNE, MARCH, MAY, MILLISECOND, MINUTE, MONDAY, MONTH, NOVEMBER, OCTOBER, PM, SATURDAY, SECOND, SEPTEMBER, SUNDAY, THURSDAY, time, TUESDAY, UNDECIMBER, WEDNESDAY, WEEK_OF_MONTH, WEEK_OF_YEAR, YEAR, ZONE_OFFSET |
Constructor Summary |
---|
GregorianCalendar() Constructs a default GregorianCalendar using the current time in the default time zone with the default locale. |
[GregorianCalendar](../../java/util/GregorianCalendar.html#GregorianCalendar%28int, int, int%29)(int year, int month, int dayOfMonth) Constructs a GregorianCalendar with the given date set in the default time zone with the default locale. |
[GregorianCalendar](../../java/util/GregorianCalendar.html#GregorianCalendar%28int, int, int, int, int%29)(int year, int month, int dayOfMonth, int hourOfDay, int minute) Constructs a GregorianCalendar with the given date and time set for the default time zone with the default locale. |
[GregorianCalendar](../../java/util/GregorianCalendar.html#GregorianCalendar%28int, int, int, int, int, int%29)(int year, int month, int dayOfMonth, int hourOfDay, int minute, int second) Constructs a GregorianCalendar with the given date and time set for the default time zone with the default locale. |
GregorianCalendar(Locale aLocale) Constructs a GregorianCalendar based on the current time in the default time zone with the given locale. |
GregorianCalendar(TimeZone zone) Constructs a GregorianCalendar based on the current time in the given time zone with the default locale. |
[GregorianCalendar](../../java/util/GregorianCalendar.html#GregorianCalendar%28java.util.TimeZone, java.util.Locale%29)(TimeZone zone,Locale aLocale) Constructs a GregorianCalendar based on the current time in the given time zone with the given locale. |
Method Summary | |
---|---|
void | [add](../../java/util/GregorianCalendar.html#add%28int, int%29)(int field, int amount) Adds the specified (signed) amount of time to the given calendar field, based on the calendar's rules. |
Object | clone() Creates and returns a copy of this object. |
protected void | computeFields() Converts the time value (millisecond offset from the Epoch) to calendar field values. |
protected void | computeTime() Converts calendar field values to the time value (millisecond offset from the Epoch). |
boolean | equals(Object obj) Compares this GregorianCalendar to the specifiedObject. |
int | getActualMaximum(int field) Returns the maximum value that this calendar field could have, taking into consideration the given time value and the current values of thegetFirstDayOfWeek,getMinimalDaysInFirstWeek,getGregorianChange andgetTimeZone methods. |
int | getActualMinimum(int field) Returns the minimum value that this calendar field could have, taking into consideration the given time value and the current values of thegetFirstDayOfWeek,getMinimalDaysInFirstWeek,getGregorianChange andgetTimeZone methods. |
int | getGreatestMinimum(int field) Returns the highest minimum value for the given calendar field of this GregorianCalendar instance. |
Date | getGregorianChange() Gets the Gregorian Calendar change date. |
int | getLeastMaximum(int field) Returns the lowest maximum value for the given calendar field of this GregorianCalendar instance. |
int | getMaximum(int field) Returns the maximum value for the given calendar field of thisGregorianCalendar instance. |
int | getMinimum(int field) Returns the minimum value for the given calendar field of thisGregorianCalendar instance. |
TimeZone | getTimeZone() Gets the time zone. |
int | hashCode() Generates the hash code for this GregorianCalendar object. |
boolean | isLeapYear(int year) Determines if the given year is a leap year. |
void | [roll](../../java/util/GregorianCalendar.html#roll%28int, boolean%29)(int field, boolean up) Adds or subtracts (up/down) a single unit of time on the given time field without changing larger fields. |
void | [roll](../../java/util/GregorianCalendar.html#roll%28int, int%29)(int field, int amount) Adds a signed amount to the specified calendar field without changing larger fields. |
void | setGregorianChange(Date date) Sets the GregorianCalendar change date. |
void | setTimeZone(TimeZone zone) Sets the time zone with the given time zone value. |
Methods inherited from class java.util.Calendar |
---|
after, before, clear, clear, compareTo, complete, get, getAvailableLocales, getFirstDayOfWeek, getInstance, getInstance, getInstance, [getInstance](../../java/util/Calendar.html#getInstance%28java.util.TimeZone, java.util.Locale%29), getMinimalDaysInFirstWeek, getTime, getTimeInMillis, internalGet, isLenient, isSet, [set](../../java/util/Calendar.html#set%28int, int%29), [set](../../java/util/Calendar.html#set%28int, int, int%29), [set](../../java/util/Calendar.html#set%28int, int, int, int, int%29), [set](../../java/util/Calendar.html#set%28int, int, int, int, int, int%29), setFirstDayOfWeek, setLenient, setMinimalDaysInFirstWeek, setTime, setTimeInMillis, toString |
Methods inherited from class java.lang.Object |
---|
finalize, getClass, notify, notifyAll, wait, wait, [wait](../../java/lang/Object.html#wait%28long, int%29) |
Field Detail |
---|
BC
public static final int BC
Value of the ERA
field indicating the period before the common era (before Christ), also known as BCE. The sequence of years at the transition from BC
to AD
is ..., 2 BC, 1 BC, 1 AD, 2 AD,...
See Also:
Calendar.ERA, Constant Field Values
AD
public static final int AD
Value of the ERA
field indicating the common era (Anno Domini), also known as CE. The sequence of years at the transition from BC
to AD
is ..., 2 BC, 1 BC, 1 AD, 2 AD,...
See Also:
Calendar.ERA, Constant Field Values
Constructor Detail |
---|
GregorianCalendar
public GregorianCalendar()
Constructs a default GregorianCalendar
using the current time in the default time zone with the default locale.
GregorianCalendar
public GregorianCalendar(TimeZone zone)
Constructs a GregorianCalendar
based on the current time in the given time zone with the default locale.
Parameters:
zone
- the given time zone.
GregorianCalendar
public GregorianCalendar(Locale aLocale)
Constructs a GregorianCalendar
based on the current time in the default time zone with the given locale.
Parameters:
aLocale
- the given locale.
GregorianCalendar
public GregorianCalendar(TimeZone zone, Locale aLocale)
Constructs a GregorianCalendar
based on the current time in the given time zone with the given locale.
Parameters:
zone
- the given time zone.
aLocale
- the given locale.
GregorianCalendar
public GregorianCalendar(int year, int month, int dayOfMonth)
Constructs a GregorianCalendar
with the given date set in the default time zone with the default locale.
Parameters:
year
- the value used to set the YEAR
calendar field in the calendar.
month
- the value used to set the MONTH
calendar field in the calendar. Month value is 0-based. e.g., 0 for January.
dayOfMonth
- the value used to set the DAY_OF_MONTH
calendar field in the calendar.
GregorianCalendar
public GregorianCalendar(int year, int month, int dayOfMonth, int hourOfDay, int minute)
Constructs a GregorianCalendar
with the given date and time set for the default time zone with the default locale.
Parameters:
year
- the value used to set the YEAR
calendar field in the calendar.
month
- the value used to set the MONTH
calendar field in the calendar. Month value is 0-based. e.g., 0 for January.
dayOfMonth
- the value used to set the DAY_OF_MONTH
calendar field in the calendar.
hourOfDay
- the value used to set the HOUR_OF_DAY
calendar field in the calendar.
minute
- the value used to set the MINUTE
calendar field in the calendar.
GregorianCalendar
public GregorianCalendar(int year, int month, int dayOfMonth, int hourOfDay, int minute, int second)
Constructs a GregorianCalendar with the given date and time set for the default time zone with the default locale.
Parameters:
year
- the value used to set the YEAR
calendar field in the calendar.
month
- the value used to set the MONTH
calendar field in the calendar. Month value is 0-based. e.g., 0 for January.
dayOfMonth
- the value used to set the DAY_OF_MONTH
calendar field in the calendar.
hourOfDay
- the value used to set the HOUR_OF_DAY
calendar field in the calendar.
minute
- the value used to set the MINUTE
calendar field in the calendar.
second
- the value used to set the SECOND
calendar field in the calendar.
Method Detail |
---|
setGregorianChange
public void setGregorianChange(Date date)
Sets the 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 toDate(Long.MAX_VALUE)
. To obtain a pure Gregorian calendar, set the change date to Date(Long.MIN_VALUE)
.
Parameters:
date
- the given Gregorian cutover date.
getGregorianChange
public final Date getGregorianChange()
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.
Returns:
the Gregorian cutover date for this GregorianCalendar
object.
isLeapYear
public boolean isLeapYear(int year)
Determines if the given year is a leap year. Returns true
if the given year is a leap year. To specify BC year numbers,1 - year number
must be given. For example, year BC 4 is specified as -3.
Parameters:
year
- the given year.
Returns:
true
if the given year is a leap year; false
otherwise.
equals
public boolean equals(Object obj)
Compares this GregorianCalendar
to the specifiedObject
. The result is true
if and only if the argument is a GregorianCalendar
object that represents the same time value (millisecond offset from the Epoch) under the sameCalendar
parameters and Gregorian change date as this object.
Overrides:
[equals](../../java/util/Calendar.html#equals%28java.lang.Object%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
obj
- the object to compare with.
Returns:
true
if this object is equal to obj
;false
otherwise.
See Also:
hashCode
public int hashCode()
Generates the hash code for this GregorianCalendar
object.
Overrides:
[hashCode](../../java/util/Calendar.html#hashCode%28%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Returns:
a hash code value for this object.
See Also:
Object.equals(java.lang.Object), Hashtable
add
public void add(int field, int amount)
Adds the specified (signed) amount of time to the given calendar field, based on the calendar's rules.
Add rule 1. The value of field
after the call minus the value of field
before the call is amount
, modulo any overflow that has occurred infield
. 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 afterfield
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. HOUR
is a smaller field thanDAY_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.
Specified by:
[add](../../java/util/Calendar.html#add%28int, int%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
field
- the calendar field.
amount
- the amount of date or time to be added to the field.
Throws:
[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")
- if field
isZONE_OFFSET
, DST_OFFSET
, or unknown, or if any calendar fields have out-of-range values in non-lenient mode.
See Also:
[Calendar.roll(int,int)](../../java/util/Calendar.html#roll%28int, int%29), [Calendar.set(int,int)](../../java/util/Calendar.html#set%28int, int%29)
roll
public void roll(int field, boolean up)
Adds or subtracts (up/down) a single unit of time on the given time field without changing larger fields.
Example: Consider a GregorianCalendar
originally set to December 31, 1999. Calling [roll(Calendar.MONTH, true)](../../java/util/GregorianCalendar.html#roll%28int, boolean%29) sets the calendar to January 31, 1999. The YEAR
field is unchanged because it is a larger field than MONTH
.
Specified by:
[roll](../../java/util/Calendar.html#roll%28int, boolean%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
up
- indicates if the value of the specified calendar field is to be rolled up or rolled down. Use true
if rolling up, false
otherwise.
field
- the time field.
Throws:
[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")
- if field
isZONE_OFFSET
, DST_OFFSET
, or unknown, or if any calendar fields have out-of-range values in non-lenient mode.
See Also:
[add(int,int)](../../java/util/GregorianCalendar.html#add%28int, int%29), [Calendar.set(int,int)](../../java/util/Calendar.html#set%28int, int%29)
roll
public void roll(int field, int amount)
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 Calendar.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 anIllegalArgumentException
is thrown.
Example: Consider a GregorianCalendar
originally set to August 31, 1999. Calling roll(Calendar.MONTH, 8)
sets the calendar to April 30, 1999. Using aGregorianCalendar
, the DAY_OF_MONTH
field cannot be 31 in the month April. DAY_OF_MONTH
is set to the closest possible value, 30. The YEAR
field maintains the value of 1999 because it is a larger field than MONTH
.
Example: Consider a GregorianCalendar
originally set to Sunday June 6, 1999. Callingroll(Calendar.WEEK_OF_MONTH, -1)
sets the calendar to Tuesday June 1, 1999, whereas callingadd(Calendar.WEEK_OF_MONTH, -1)
sets the calendar to Sunday May 30, 1999. This is because the roll rule imposes an additional constraint: The MONTH
must not change when theWEEK_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 DAY_OF_WEEK
, an invariant when changing the WEEK_OF_MONTH
, is set to Tuesday, the closest possible value to Sunday (where Sunday is the first day of the week).
Overrides:
[roll](../../java/util/Calendar.html#roll%28int, int%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
field
- the calendar field.
amount
- the signed amount to add to field
.
Throws:
[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")
- if field
isZONE_OFFSET
, DST_OFFSET
, or unknown, or if any calendar fields have out-of-range values in non-lenient mode.
Since:
1.2
See Also:
[roll(int,boolean)](../../java/util/GregorianCalendar.html#roll%28int, boolean%29), [add(int,int)](../../java/util/GregorianCalendar.html#add%28int, int%29), [Calendar.set(int,int)](../../java/util/Calendar.html#set%28int, int%29)
getMinimum
public int getMinimum(int field)
Returns the minimum value for the given calendar field of thisGregorianCalendar
instance. The minimum value is defined as the smallest value returned by the get method for any possible time value, taking into consideration the current values of thegetFirstDayOfWeek,getMinimalDaysInFirstWeek,getGregorianChange
andgetTimeZone methods.
Specified by:
[getMinimum](../../java/util/Calendar.html#getMinimum%28int%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
field
- the calendar field.
Returns:
the minimum value for the given calendar field.
See Also:
getMaximum(int), getGreatestMinimum(int), getLeastMaximum(int), getActualMinimum(int), getActualMaximum(int)
getMaximum
public int getMaximum(int field)
Returns the maximum value for the given calendar field of thisGregorianCalendar
instance. The maximum value is defined as the largest value returned by the get method for any possible time value, taking into consideration the current values of thegetFirstDayOfWeek,getMinimalDaysInFirstWeek,getGregorianChange
andgetTimeZone methods.
Specified by:
[getMaximum](../../java/util/Calendar.html#getMaximum%28int%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
field
- the calendar field.
Returns:
the maximum value for the given calendar field.
See Also:
getMinimum(int), getGreatestMinimum(int), getLeastMaximum(int), getActualMinimum(int), getActualMaximum(int)
getGreatestMinimum
public int getGreatestMinimum(int field)
Returns the highest minimum value for the given calendar field of this GregorianCalendar
instance. The highest minimum value is defined as the largest value returned bygetActualMinimum(int) for any possible time value, taking into consideration the current values of thegetFirstDayOfWeek,getMinimalDaysInFirstWeek,getGregorianChange
andgetTimeZone methods.
Specified by:
[getGreatestMinimum](../../java/util/Calendar.html#getGreatestMinimum%28int%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
field
- the calendar field.
Returns:
the highest minimum value for the given calendar field.
See Also:
getMinimum(int), getMaximum(int), getLeastMaximum(int), getActualMinimum(int), getActualMaximum(int)
getLeastMaximum
public int getLeastMaximum(int field)
Returns the lowest maximum value for the given calendar field of this GregorianCalendar
instance. The lowest maximum value is defined as the smallest value returned bygetActualMaximum(int) for any possible time value, taking into consideration the current values of thegetFirstDayOfWeek,getMinimalDaysInFirstWeek,getGregorianChange
andgetTimeZone methods.
Specified by:
[getLeastMaximum](../../java/util/Calendar.html#getLeastMaximum%28int%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
field
- the calendar field
Returns:
the lowest maximum value for the given calendar field.
See Also:
getMinimum(int), getMaximum(int), getGreatestMinimum(int), getActualMinimum(int), getActualMaximum(int)
getActualMinimum
public int getActualMinimum(int field)
Returns the minimum value that this calendar field could have, taking into consideration the given time value and the current values of thegetFirstDayOfWeek,getMinimalDaysInFirstWeek,getGregorianChange
andgetTimeZone methods.
For example, if the Gregorian change date is January 10, 1970 and the date of this GregorianCalendar
is January 20, 1970, the actual minimum value of theDAY_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.
Overrides:
[getActualMinimum](../../java/util/Calendar.html#getActualMinimum%28int%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
field
- the calendar field
Returns:
the minimum of the given field for the time value of this GregorianCalendar
Since:
1.2
See Also:
getMinimum(int), getMaximum(int), getGreatestMinimum(int), getLeastMaximum(int), getActualMaximum(int)
getActualMaximum
public int getActualMaximum(int field)
Returns the maximum value that this calendar field could have, taking into consideration the given time value and the current values of thegetFirstDayOfWeek,getMinimalDaysInFirstWeek,getGregorianChange
andgetTimeZone methods. For example, if the date of this instance is February 1, 2004, the actual maximum value of the 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.
Overrides:
[getActualMaximum](../../java/util/Calendar.html#getActualMaximum%28int%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
field
- the calendar field
Returns:
the maximum of the given field for the time value of this GregorianCalendar
Since:
1.2
See Also:
getMinimum(int), getMaximum(int), getGreatestMinimum(int), getLeastMaximum(int), getActualMinimum(int)
clone
public Object clone()
Description copied from class: [Calendar](../../java/util/Calendar.html#clone%28%29)
Creates and returns a copy of this object.
Overrides:
[clone](../../java/util/Calendar.html#clone%28%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Returns:
a copy of this object.
See Also:
getTimeZone
public TimeZone getTimeZone()
Description copied from class: [Calendar](../../java/util/Calendar.html#getTimeZone%28%29)
Gets the time zone.
Overrides:
[getTimeZone](../../java/util/Calendar.html#getTimeZone%28%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Returns:
the time zone object associated with this calendar.
setTimeZone
public void setTimeZone(TimeZone zone)
Description copied from class: [Calendar](../../java/util/Calendar.html#setTimeZone%28java.util.TimeZone%29)
Sets the time zone with the given time zone value.
Overrides:
[setTimeZone](../../java/util/Calendar.html#setTimeZone%28java.util.TimeZone%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Parameters:
zone
- the given time zone.
computeFields
protected void computeFields()
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 thecomplete
method.
Specified by:
[computeFields](../../java/util/Calendar.html#computeFields%28%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
See Also:
computeTime
protected void computeTime()
Converts calendar field values to the time value (millisecond offset from the Epoch).
Specified by:
[computeTime](../../java/util/Calendar.html#computeTime%28%29)
in class [Calendar](../../java/util/Calendar.html "class in java.util")
Throws:
[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")
- if any calendar fields are invalid.
See Also:
Calendar.complete(), Calendar.computeFields()
Submit a bug or feature
For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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