Module java.base
Package java.util

Class Calendar

  • All Implemented Interfaces:
    Serializable,Cloneable,Comparable<Calendar>
    Direct Known Subclasses:
    GregorianCalendar

    public abstract classCalendarextendsObjectimplementsSerializable,Cloneable,Comparable<Calendar>
    TheCalendar class is an abstract class that provides methods for converting between a specific instant in time and a set ofcalendar fields such asYEAR,MONTH,DAY_OF_MONTH,HOUR, and so on, and for manipulating the calendar fields, such as getting the date of the next week. An instant in time can be represented by a millisecond value that is an offset from theEpoch, January 1, 1970 00:00:00.000 GMT (Gregorian).

    The class also provides additional fields and methods for implementing a concrete calendar system outside the package. Those fields and methods are defined asprotected.

    Like other locale-sensitive classes,Calendar provides a class method,getInstance, for getting a generally useful object of this type.Calendar'sgetInstance method returns aCalendar object whose calendar fields have been initialized with the current date and time:

         Calendar rightNow = Calendar.getInstance();

    ACalendar object can produce all the calendar field values needed to implement the date-time formatting for a particular language and calendar style (for example, Japanese-Gregorian, Japanese-Traditional).Calendar defines the range of values returned by certain calendar fields, as well as their meaning. For example, the first month of the calendar system has valueMONTH == JANUARY for all calendars. Other values are defined by the concrete subclass, such asERA. See individual field documentation and subclass documentation for details.

    Getting and Setting Calendar Field Values

    The calendar field values can be set by calling theset methods. Any field values set in aCalendar will not be interpreted until it needs to calculate its time value (milliseconds from the Epoch) or values of the calendar fields. Calling theget,getTimeInMillis,getTime,add androll involves such calculation.

    Leniency

    Calendar has two modes for interpreting the calendar fields,lenient andnon-lenient. When aCalendar is in lenient mode, it accepts a wider range of calendar field values than it produces. When aCalendar recomputes calendar field values for return byget(), all of the calendar fields are normalized. For example, a lenientGregorianCalendar interpretsMONTH == JANUARY,DAY_OF_MONTH == 32 as February 1.

    When aCalendar is in non-lenient mode, it throws an exception if there is any inconsistency in its calendar fields. For example, aGregorianCalendar always producesDAY_OF_MONTH values between 1 and the length of the month. A non-lenientGregorianCalendar throws an exception upon calculating its time or calendar field values if any out-of-range field value has been set.

    First Week

    Calendar defines a locale-specific seven day week using two parameters: the first day of the week and the minimal days in first week (from 1 to 7). These numbers are taken from the locale resource data or the locale itself when aCalendar is constructed. If the designated locale contains "fw" and/or "rg" Unicode extensions, the first day of the week will be obtained according to those extensions. If both "fw" and "rg" are specified, the value from the "fw" extension supersedes the implicit one from the "rg" extension. They may also be specified explicitly through the methods for setting their values.

    When setting or getting theWEEK_OF_MONTH orWEEK_OF_YEAR fields,Calendar must determine the first week of the month or year as a reference point. The first week of a month or year is defined as the earliest seven day period beginning ongetFirstDayOfWeek() and containing at leastgetMinimalDaysInFirstWeek() days of that month or year. Weeks numbered ..., -1, 0 precede the first week; weeks numbered 2, 3,... follow it. Note that the normalized numbering returned byget() may be different. For example, a specificCalendar subclass may designate the week before week 1 of a year as weekn of the previous year.

    Calendar Fields Resolution

    When computing a date and time from the calendar fields, there may be insufficient information for the computation (such as only year and month with no day of month), or there may be inconsistent information (such as Tuesday, July 15, 1996 (Gregorian) -- July 15, 1996 is actually a Monday).Calendar will resolve calendar field values to determine the date and time in the following way.

    If there is any conflict in calendar field values,Calendar gives priorities to calendar fields that have been set more recently. The following are the default combinations of the calendar fields. The most recent combination, as determined by the most recently set single field, will be used.

    For the date fields:

     YEAR + MONTH + DAY_OF_MONTH YEAR + MONTH + WEEK_OF_MONTH + DAY_OF_WEEK YEAR + MONTH + DAY_OF_WEEK_IN_MONTH + DAY_OF_WEEK YEAR + DAY_OF_YEAR YEAR + DAY_OF_WEEK + WEEK_OF_YEAR
    For the time of day fields:
     HOUR_OF_DAY AM_PM + HOUR

    If there are any calendar fields whose values haven't been set in the selected field combination,Calendar uses their default values. The default value of each field may vary by concrete calendar systems. For example, inGregorianCalendar, the default of a field is the same as that of the start of the Epoch: i.e.,YEAR = 1970,MONTH = JANUARY,DAY_OF_MONTH = 1, etc.

    Note: There are certain possible ambiguities in interpretation of certain singular times, which are resolved in the following ways:

    1. 23:59 is the last minute of the day and 00:00 is the first minute of the next day. Thus, 23:59 on Dec 31, 1999 < 00:00 on Jan 1, 2000 < 00:01 on Jan 1, 2000.
    2. Although historically not precise, midnight also belongs to "am", and noon belongs to "pm", so on the same day, 12:00 am (midnight) < 12:01 am, and 12:00 pm (noon) < 12:01 pm

    The date or time format strings are not part of the definition of a calendar, as those must be modifiable or overridable by the user at runtime. UseDateFormat to format dates.

    Field Manipulation

    The calendar fields can be changed using three methods:set(),add(), androll().

    set(f, value) changes calendar fieldf tovalue. In addition, it sets an internal member variable to indicate that calendar fieldf has been changed. Although calendar fieldf is changed immediately, the calendar's time value in milliseconds is not recomputed until the next call toget(),getTime(),getTimeInMillis(),add(), orroll() is made. Thus, multiple calls toset() do not trigger multiple, unnecessary computations. As a result of changing a calendar field usingset(), other calendar fields may also change, depending on the calendar field, the calendar field value, and the calendar system. In addition,get(f) will not necessarily returnvalue set by the call to theset method after the calendar fields have been recomputed. The specifics are determined by the concrete calendar class.

    Example: Consider aGregorianCalendar originally set to August 31, 1999. Callingset(Calendar.MONTH, Calendar.SEPTEMBER) sets the date to September 31, 1999. This is a temporary internal representation that resolves to October 1, 1999 ifgetTime()is then called. However, a call toset(Calendar.DAY_OF_MONTH, 30) before the call togetTime() sets the date to September 30, 1999, since no recomputation occurs afterset() itself.

    add(f, delta) addsdelta to fieldf. This is equivalent to callingset(f, get(f) + delta) with two adjustments:

    Add rule 1. The value of fieldf after the call minus the value of fieldf before the call isdelta, modulo any overflow that has occurred in fieldf. 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 fieldf is changed or other constraints, such as time zone offset changes, 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.

    In addition, unlikeset(),add() forces an immediate recomputation of the calendar's milliseconds and all fields.

    Example: Consider aGregorianCalendar originally set to August 31, 1999. Callingadd(Calendar.MONTH, 13) sets the calendar to September 30, 2000.Add rule 1 sets theMONTH field to September, since adding 13 months to August gives September of the next year. SinceDAY_OF_MONTH cannot be 31 in September in aGregorianCalendar,add rule 2 sets theDAY_OF_MONTH to 30, the closest possible value. Although it is a smaller field,DAY_OF_WEEK is not adjusted by rule 2, since it is expected to change when the month changes in aGregorianCalendar.

    roll(f, delta) addsdelta to fieldf without changing larger fields. This is equivalent to callingadd(f, delta) with the following adjustment:

    Roll rule. Larger fields are unchanged after the call. A larger field represents a larger unit of time.DAY_OF_MONTH is a larger field thanHOUR.

    Example: SeeGregorianCalendar.roll(int, int).

    Usage model. To motivate the behavior ofadd() androll(), consider a user interface component with increment and decrement buttons for the month, day, and year, and an underlyingGregorianCalendar. If the interface reads January 31, 1999 and the user presses the month increment button, what should it read? If the underlying implementation usesset(), it might read March 3, 1999. A better result would be February 28, 1999. Furthermore, if the user presses the month increment button again, it should read March 31, 1999, not March 28, 1999. By saving the original date and using eitheradd() orroll(), depending on whether larger fields should be affected, the user interface can behave as most users will intuitively expect.

    Since:
    1.1
    See Also:
    System.currentTimeMillis(),Date,GregorianCalendar,TimeZone,DateFormat,Serialized Form
    • Nested Class Summary

      Nested Classes 
      Modifier and TypeClassDescription
      static class Calendar.Builder
      Calendar.Builder is used for creating aCalendar from various date-time parameters.
    • Field Summary

      Fields 
      Modifier and TypeFieldDescription
      static intALL_STYLES
      A style specifier forgetDisplayNames indicating names in all styles, such as "January" and "Jan".
      static intAM
      Value of theAM_PM field indicating the period of the day from midnight to just before noon.
      static intAM_PM
      Field number forget andset indicating whether theHOUR is before or after noon.
      static intAPRIL
      Value of theMONTH field indicating the fourth month of the year in the Gregorian and Julian calendars.
      protected booleanareFieldsSet
      True iffields[] are in sync with the currently set time.
      static intAUGUST
      Value of theMONTH field indicating the eighth month of the year in the Gregorian and Julian calendars.
      static intDATE
      Field number forget andset indicating the day of the month.
      static intDAY_OF_MONTH
      Field number forget andset indicating the day of the month.
      static intDAY_OF_WEEK
      Field number forget andset indicating the day of the week.
      static intDAY_OF_WEEK_IN_MONTH
      Field number forget andset indicating the ordinal number of the day of the week within the current month.
      static intDAY_OF_YEAR
      Field number forget andset indicating the day number within the current year.
      static intDECEMBER
      Value of theMONTH field indicating the twelfth month of the year in the Gregorian and Julian calendars.
      static intDST_OFFSET
      Field number forget andset indicating the daylight saving offset in milliseconds.
      static intERA
      Field number forget andset indicating the era, e.g., AD or BC in the Julian calendar.
      static intFEBRUARY
      Value of theMONTH field indicating the second month of the year in the Gregorian and Julian calendars.
      static intFIELD_COUNT
      The number of distinct fields recognized byget andset.
      protected int[]fields
      The calendar field values for the currently set time for this calendar.
      static intFRIDAY
      Value of theDAY_OF_WEEK field indicating Friday.
      static intHOUR
      Field number forget andset indicating the hour of the morning or afternoon.
      static intHOUR_OF_DAY
      Field number forget andset indicating the hour of the day.
      protected boolean[]isSet
      The flags which tell if a specified calendar field for the calendar is set.
      protected booleanisTimeSet
      True if then the value oftime is valid.
      static intJANUARY
      Value of theMONTH field indicating the first month of the year in the Gregorian and Julian calendars.
      static intJULY
      Value of theMONTH field indicating the seventh month of the year in the Gregorian and Julian calendars.
      static intJUNE
      Value of theMONTH field indicating the sixth month of the year in the Gregorian and Julian calendars.
      static intLONG
      A style specifier forgetDisplayName andgetDisplayNames equivalent toLONG_FORMAT.
      static intLONG_FORMAT
      A style specifier forgetDisplayName andgetDisplayNames indicating a long name used for format.
      static intLONG_STANDALONE
      A style specifier forgetDisplayName andgetDisplayNames indicating a long name used independently, such as a month name as calendar headers.
      static intMARCH
      Value of theMONTH field indicating the third month of the year in the Gregorian and Julian calendars.
      static intMAY
      Value of theMONTH field indicating the fifth month of the year in the Gregorian and Julian calendars.
      static intMILLISECOND
      Field number forget andset indicating the millisecond within the second.
      static intMINUTE
      Field number forget andset indicating the minute within the hour.
      static intMONDAY
      Value of theDAY_OF_WEEK field indicating Monday.
      static intMONTH
      Field number forget andset indicating the month.
      static intNARROW_FORMAT
      A style specifier forgetDisplayName andgetDisplayNames indicating a narrow name used for format.
      static intNARROW_STANDALONE
      A style specifier forgetDisplayName andgetDisplayNames indicating a narrow name independently.
      static intNOVEMBER
      Value of theMONTH field indicating the eleventh month of the year in the Gregorian and Julian calendars.
      static intOCTOBER
      Value of theMONTH field indicating the tenth month of the year in the Gregorian and Julian calendars.
      static intPM
      Value of theAM_PM field indicating the period of the day from noon to just before midnight.
      static intSATURDAY
      Value of theDAY_OF_WEEK field indicating Saturday.
      static intSECOND
      Field number forget andset indicating the second within the minute.
      static intSEPTEMBER
      Value of theMONTH field indicating the ninth month of the year in the Gregorian and Julian calendars.
      static intSHORT
      A style specifier forgetDisplayName andgetDisplayNames equivalent toSHORT_FORMAT.
      static intSHORT_FORMAT
      A style specifier forgetDisplayName andgetDisplayNames indicating a short name used for format.
      static intSHORT_STANDALONE
      A style specifier forgetDisplayName andgetDisplayNames indicating a short name used independently, such as a month abbreviation as calendar headers.
      static intSUNDAY
      Value of theDAY_OF_WEEK field indicating Sunday.
      static intTHURSDAY
      Value of theDAY_OF_WEEK field indicating Thursday.
      protected longtime
      The currently set time for this calendar, expressed in milliseconds after January 1, 1970, 0:00:00 GMT.
      static intTUESDAY
      Value of theDAY_OF_WEEK field indicating Tuesday.
      static intUNDECIMBER
      Value of theMONTH field indicating the thirteenth month of the year.
      static intWEDNESDAY
      Value of theDAY_OF_WEEK field indicating Wednesday.
      static intWEEK_OF_MONTH
      Field number forget andset indicating the week number within the current month.
      static intWEEK_OF_YEAR
      Field number forget andset indicating the week number within the current year.
      static intYEAR
      Field number forget andset indicating the year.
      static intZONE_OFFSET
      Field number forget andset indicating the raw offset from GMT in milliseconds.
    • Constructor Summary

      Constructors 
      ModifierConstructorDescription
      protectedCalendar()
      Constructs a Calendar with the default time zone and the defaultFORMAT locale.
      protectedCalendar​(TimeZone zone,Locale aLocale)
      Constructs a calendar with the specified time zone and locale.
    • Method Summary

      All Methods Static Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and TypeMethodDescription
      abstract voidadd​(int field, int amount)
      Adds or subtracts the specified amount of time to the given calendar field, based on the calendar's rules.
      booleanafter​(Object when)
      Returns whether thisCalendar represents a time after the time represented by the specifiedObject.
      booleanbefore​(Object when)
      Returns whether thisCalendar represents a time before the time represented by the specifiedObject.
      voidclear()
      Sets all the calendar field values and the time value (millisecond offset from theEpoch) of thisCalendar undefined.
      voidclear​(int field)
      Sets the given calendar field value and the time value (millisecond offset from theEpoch) of thisCalendar undefined.
      Objectclone()
      Creates and returns a copy of this object.
      intcompareTo​(Calendar anotherCalendar)
      Compares the time values (millisecond offsets from theEpoch) represented by twoCalendar objects.
      protected voidcomplete()
      Fills in any unset fields in the calendar fields.
      protected abstract voidcomputeFields()
      Converts the current millisecond time valuetime to calendar field values infields[].
      protected abstract voidcomputeTime()
      Converts the current calendar field values infields[] to the millisecond time valuetime.
      booleanequals​(Object obj)
      Compares thisCalendar to the specifiedObject.
      intget​(int field)
      Returns the value of the given calendar field.
      intgetActualMaximum​(int field)
      Returns the maximum value that the specified calendar field could have, given the time value of thisCalendar.
      intgetActualMinimum​(int field)
      Returns the minimum value that the specified calendar field could have, given the time value of thisCalendar.
      staticSet<String>getAvailableCalendarTypes()
      Returns an unmodifiableSet containing all calendar types supported byCalendar in the runtime environment.
      staticLocale[]getAvailableLocales()
      Returns an array of all locales for which thegetInstance methods of this class can return localized instances.
      StringgetCalendarType()
      Returns the calendar type of thisCalendar.
      StringgetDisplayName​(int field, int style,Locale locale)
      Returns the string representation of the calendarfield value in the givenstyle andlocale.
      Map<String,​Integer>getDisplayNames​(int field, int style,Locale locale)
      Returns aMap containing all names of the calendarfield in the givenstyle andlocale and their corresponding field values.
      intgetFirstDayOfWeek()
      Gets what the first day of the week is; e.g.,SUNDAY in the U.S.,MONDAY in France.
      abstract intgetGreatestMinimum​(int field)
      Returns the highest minimum value for the given calendar field of thisCalendar instance.
      staticCalendargetInstance()
      Gets a calendar using the default time zone and locale.
      staticCalendargetInstance​(Locale aLocale)
      Gets a calendar using the default time zone and specified locale.
      staticCalendargetInstance​(TimeZone zone)
      Gets a calendar using the specified time zone and default locale.
      staticCalendargetInstance​(TimeZone zone,Locale aLocale)
      Gets a calendar with the specified time zone and locale.
      abstract intgetLeastMaximum​(int field)
      Returns the lowest maximum value for the given calendar field of thisCalendar instance.
      abstract intgetMaximum​(int field)
      Returns the maximum value for the given calendar field of thisCalendar instance.
      intgetMinimalDaysInFirstWeek()
      Gets what the minimal days required in the first week of the year are; e.g., if the first week is defined as one that contains the first day of the first month of a year, this method returns 1.
      abstract intgetMinimum​(int field)
      Returns the minimum value for the given calendar field of thisCalendar instance.
      DategetTime()
      Returns aDate object representing thisCalendar's time value (millisecond offset from theEpoch").
      longgetTimeInMillis()
      Returns this Calendar's time value in milliseconds.
      TimeZonegetTimeZone()
      Gets the time zone.
      intgetWeeksInWeekYear()
      Returns the number of weeks in the week year represented by thisCalendar.
      intgetWeekYear()
      Returns the week year represented by thisCalendar.
      inthashCode()
      Returns a hash code for this calendar.
      protected intinternalGet​(int field)
      Returns the value of the given calendar field.
      booleanisLenient()
      Tells whether date/time interpretation is to be lenient.
      booleanisSet​(int field)
      Determines if the given calendar field has a value set, including cases that the value has been set by internal fields calculations triggered by aget method call.
      booleanisWeekDateSupported()
      Returns whether thisCalendar supports week dates.
      abstract voidroll​(int field, boolean up)
      Adds or subtracts (up/down) a single unit of time on the given time field without changing larger fields.
      voidroll​(int field, int amount)
      Adds the specified (signed) amount to the specified calendar field without changing larger fields.
      voidset​(int field, int value)
      Sets the given calendar field to the given value.
      voidset​(int year, int month, int date)
      Sets the values for the calendar fieldsYEAR,MONTH, andDAY_OF_MONTH.
      voidset​(int year, int month, int date, int hourOfDay, int minute)
      Sets the values for the calendar fieldsYEAR,MONTH,DAY_OF_MONTH,HOUR_OF_DAY, andMINUTE.
      voidset​(int year, int month, int date, int hourOfDay, int minute, int second)
      Sets the values for the fieldsYEAR,MONTH,DAY_OF_MONTH,HOUR_OF_DAY,MINUTE, andSECOND.
      voidsetFirstDayOfWeek​(int value)
      Sets what the first day of the week is; e.g.,SUNDAY in the U.S.,MONDAY in France.
      voidsetLenient​(boolean lenient)
      Specifies whether or not date/time interpretation is to be lenient.
      voidsetMinimalDaysInFirstWeek​(int value)
      Sets what the minimal days required in the first week of the year are; For example, if the first week is defined as one that contains the first day of the first month of a year, call this method with value 1.
      voidsetTime​(Date date)
      Sets this Calendar's time with the givenDate.
      voidsetTimeInMillis​(long millis)
      Sets this Calendar's current time from the given long value.
      voidsetTimeZone​(TimeZone value)
      Sets the time zone with the given time zone value.
      voidsetWeekDate​(int weekYear, int weekOfYear, int dayOfWeek)
      Sets the date of thisCalendar with the given date specifiers - week year, week of year, and day of week.
      InstanttoInstant()
      Converts this object to anInstant.
      StringtoString()
      Return a string representation of this calendar.
    • Field Detail

      • YEAR

        public static final int YEAR
        Field number forget andset indicating the year. This is a calendar-specific value; see subclass documentation.
        See Also:
        Constant Field Values
      • WEEK_OF_YEAR

        public static final int WEEK_OF_YEAR
        Field number forget andset indicating the week number within the current year. The first week of the year, as defined bygetFirstDayOfWeek() andgetMinimalDaysInFirstWeek(), has value 1. Subclasses define the value ofWEEK_OF_YEAR for days before the first week of the year.
        See Also:
        getFirstDayOfWeek(),getMinimalDaysInFirstWeek(),Constant Field Values
      • WEEK_OF_MONTH

        public static final int WEEK_OF_MONTH
        Field number forget andset indicating the week number within the current month. The first week of the month, as defined bygetFirstDayOfWeek() andgetMinimalDaysInFirstWeek(), has value 1. Subclasses define the value ofWEEK_OF_MONTH for days before the first week of the month.
        See Also:
        getFirstDayOfWeek(),getMinimalDaysInFirstWeek(),Constant Field Values
      • DATE

        public static final int DATE
        Field number forget andset indicating the day of the month. This is a synonym forDAY_OF_MONTH. The first day of the month has value 1.
        See Also:
        DAY_OF_MONTH,Constant Field Values
      • DAY_OF_MONTH

        public static final int DAY_OF_MONTH
        Field number forget andset indicating the day of the month. This is a synonym forDATE. The first day of the month has value 1.
        See Also:
        DATE,Constant Field Values
      • DAY_OF_YEAR

        public static final int DAY_OF_YEAR
        Field number forget andset indicating the day number within the current year. The first day of the year has value 1.
        See Also:
        Constant Field Values
      • DAY_OF_WEEK_IN_MONTH

        public static final int DAY_OF_WEEK_IN_MONTH
        Field number forget andset indicating the ordinal number of the day of the week within the current month. Together with theDAY_OF_WEEK field, this uniquely specifies a day within a month. UnlikeWEEK_OF_MONTH andWEEK_OF_YEAR, this field's value doesnot depend ongetFirstDayOfWeek() orgetMinimalDaysInFirstWeek().DAY_OF_MONTH 1 through7 always correspond toDAY_OF_WEEK_IN_MONTH 1;8 through14 correspond toDAY_OF_WEEK_IN_MONTH 2, and so on.DAY_OF_WEEK_IN_MONTH 0 indicates the week beforeDAY_OF_WEEK_IN_MONTH 1. Negative values count back from the end of the month, so the last Sunday of a month is specified asDAY_OF_WEEK = SUNDAY, DAY_OF_WEEK_IN_MONTH = -1. Because negative values count backward they will usually be aligned differently within the month than positive values. For example, if a month has 31 days,DAY_OF_WEEK_IN_MONTH -1 will overlapDAY_OF_WEEK_IN_MONTH 5 and the end of4.
        See Also:
        DAY_OF_WEEK,WEEK_OF_MONTH,Constant Field Values
      • AM_PM

        public static final int AM_PM
        Field number forget andset indicating whether theHOUR is before or after noon. E.g., at 10:04:15.250 PM theAM_PM isPM.
        See Also:
        AM,PM,HOUR,Constant Field Values
      • HOUR

        public static final int HOUR
        Field number forget andset indicating the hour of the morning or afternoon.HOUR is used for the 12-hour clock (0 - 11). Noon and midnight are represented by 0, not by 12. E.g., at 10:04:15.250 PM theHOUR is 10.
        See Also:
        AM_PM,HOUR_OF_DAY,Constant Field Values
      • HOUR_OF_DAY

        public static final int HOUR_OF_DAY
        Field number forget andset indicating the hour of the day.HOUR_OF_DAY is used for the 24-hour clock. E.g., at 10:04:15.250 PM theHOUR_OF_DAY is 22.
        See Also:
        HOUR,Constant Field Values
      • MINUTE

        public static final int MINUTE
        Field number forget andset indicating the minute within the hour. E.g., at 10:04:15.250 PM theMINUTE is 4.
        See Also:
        Constant Field Values
      • SECOND

        public static final int SECOND
        Field number forget andset indicating the second within the minute. E.g., at 10:04:15.250 PM theSECOND is 15.
        See Also:
        Constant Field Values
      • MILLISECOND

        public static final int MILLISECOND
        Field number forget andset indicating the millisecond within the second. E.g., at 10:04:15.250 PM theMILLISECOND is 250.
        See Also:
        Constant Field Values
      • ZONE_OFFSET

        public static final int ZONE_OFFSET
        Field number forget andset indicating the raw offset from GMT in milliseconds.

        This field reflects the correct GMT offset value of the time zone of thisCalendar if theTimeZone implementation subclass supports historical GMT offset changes.

        See Also:
        Constant Field Values
      • DST_OFFSET

        public static final int DST_OFFSET
        Field number forget andset indicating the daylight saving offset in milliseconds.

        This field reflects the correct daylight saving offset value of the time zone of thisCalendar if theTimeZone implementation subclass supports historical Daylight Saving Time schedule changes.

        See Also:
        Constant Field Values
      • FIELD_COUNT

        public static final int FIELD_COUNT
        The number of distinct fields recognized byget andset. Field numbers range from0..FIELD_COUNT-1.
        See Also:
        Constant Field Values
      • JANUARY

        public static final int JANUARY
        Value of theMONTH field indicating the first month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • FEBRUARY

        public static final int FEBRUARY
        Value of theMONTH field indicating the second month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • MARCH

        public static final int MARCH
        Value of theMONTH field indicating the third month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • APRIL

        public static final int APRIL
        Value of theMONTH field indicating the fourth month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • MAY

        public static final int MAY
        Value of theMONTH field indicating the fifth month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • JUNE

        public static final int JUNE
        Value of theMONTH field indicating the sixth month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • JULY

        public static final int JULY
        Value of theMONTH field indicating the seventh month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • AUGUST

        public static final int AUGUST
        Value of theMONTH field indicating the eighth month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • SEPTEMBER

        public static final int SEPTEMBER
        Value of theMONTH field indicating the ninth month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • OCTOBER

        public static final int OCTOBER
        Value of theMONTH field indicating the tenth month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • NOVEMBER

        public static final int NOVEMBER
        Value of theMONTH field indicating the eleventh month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • DECEMBER

        public static final int DECEMBER
        Value of theMONTH field indicating the twelfth month of the year in the Gregorian and Julian calendars.
        See Also:
        Constant Field Values
      • UNDECIMBER

        public static final int UNDECIMBER
        Value of theMONTH field indicating the thirteenth month of the year. AlthoughGregorianCalendar does not use this value, lunar calendars do.
        See Also:
        Constant Field Values
      • AM

        public static final int AM
        Value of theAM_PM field indicating the period of the day from midnight to just before noon.
        See Also:
        Constant Field Values
      • PM

        public static final int PM
        Value of theAM_PM field indicating the period of the day from noon to just before midnight.
        See Also:
        Constant Field Values
      • fields

        protected int[] fields
        The calendar field values for the currently set time for this calendar. This is an array ofFIELD_COUNT integers, with index valuesERA throughDST_OFFSET.
      • isSet

        protected boolean[] isSet
        The flags which tell if a specified calendar field for the calendar is set. A new object has no fields set. After the first call to a method which generates the fields, they all remain set after that. This is an array ofFIELD_COUNT booleans, with index valuesERA throughDST_OFFSET.
      • time

        protected long time
        The currently set time for this calendar, expressed in milliseconds after January 1, 1970, 0:00:00 GMT.
        See Also:
        isTimeSet
      • isTimeSet

        protected boolean isTimeSet
        True if then the value oftime is valid. The time is made invalid by a change to an item offield[].
        See Also:
        time
      • areFieldsSet

        protected boolean areFieldsSet
        True iffields[] are in sync with the currently set time. If false, then the next attempt to get the value of a field will force a recomputation of all fields from the current value oftime.
    • Constructor Detail

      • Calendar

        protected Calendar()
        Constructs a Calendar with the default time zone and the defaultFORMAT locale.
        See Also:
        TimeZone.getDefault()
      • Calendar

        protected Calendar​(TimeZone zone,Locale aLocale)
        Constructs a calendar with the specified time zone and locale.
        Parameters:
        zone - the time zone to use
        aLocale - the locale for the week data
    • Method Detail

      • getInstance

        public static Calendar getInstance()
        Gets a calendar using the default time zone and locale. TheCalendar returned is based on the current time in the default time zone with the defaultFORMAT locale.

        If the locale contains the time zone with "tz"Unicode extension, that time zone is used instead.

        Returns:
        a Calendar.
      • getInstance

        public static Calendar getInstance​(TimeZone zone)
        Gets a calendar using the specified time zone and default locale. TheCalendar returned is based on the current time in the given time zone with the defaultFORMAT locale.
        Parameters:
        zone - the time zone to use
        Returns:
        a Calendar.
      • getInstance

        public static Calendar getInstance​(Locale aLocale)
        Gets a calendar using the default time zone and specified locale. TheCalendar returned is based on the current time in the default time zone with the given locale.

        If the locale contains the time zone with "tz"Unicode extension, that time zone is used instead.

        Parameters:
        aLocale - the locale for the week data
        Returns:
        a Calendar.
      • getInstance

        public static Calendar getInstance​(TimeZone zone,Locale aLocale)
        Gets a calendar with the specified time zone and locale. TheCalendar returned is based on the current time in the given time zone with the given locale.
        Parameters:
        zone - the time zone to use
        aLocale - the locale for the week data
        Returns:
        a Calendar.
      • getAvailableLocales

        public static Locale[] getAvailableLocales()
        Returns an array of all locales for which thegetInstance methods of this class can return localized instances. The array returned must contain at least aLocale instance equal toLocale.US.
        Returns:
        An array of locales for which localizedCalendar instances are available.
      • computeFields

        protected abstract void computeFields()
        Converts the current millisecond time valuetime to calendar field values infields[]. This allows you to sync up the calendar field values with a new time that is set for the calendar. The time isnot recomputed first; to recompute the time, then the fields, call thecomplete() method.
        See Also:
        computeTime()
      • getTime

        public final Date getTime()
        Returns aDate object representing thisCalendar's time value (millisecond offset from theEpoch").
        Returns:
        aDate representing the time value.
        See Also:
        setTime(Date),getTimeInMillis()
      • setTime

        public final void setTime​(Date date)
        Sets this Calendar's time with the givenDate.

        Note: CallingsetTime() withDate(Long.MAX_VALUE) orDate(Long.MIN_VALUE) may yield incorrect field values fromget().

        Parameters:
        date - the given Date.
        See Also:
        getTime(),setTimeInMillis(long)
      • getTimeInMillis

        public long getTimeInMillis()
        Returns this Calendar's time value in milliseconds.
        Returns:
        the current time as UTC milliseconds from the epoch.
        See Also:
        getTime(),setTimeInMillis(long)
      • setTimeInMillis

        public void setTimeInMillis​(long millis)
        Sets this Calendar's current time from the given long value.
        Parameters:
        millis - the new time in UTC milliseconds from the epoch.
        See Also:
        setTime(Date),getTimeInMillis()
      • get

        public int get​(int field)
        Returns the value of the given calendar field. In lenient mode, all calendar fields are normalized. In non-lenient mode, all calendar fields are validated and this method throws an exception if any calendar fields have out-of-range values. The normalization and validation are handled by thecomplete() method, which process is calendar system dependent.
        Parameters:
        field - the given calendar field.
        Returns:
        the value for the given calendar field.
        Throws:
        ArrayIndexOutOfBoundsException - if the specified field is out of range (field < 0 || field >= FIELD_COUNT).
        See Also:
        set(int,int),complete()
      • internalGet

        protected final int internalGet​(int field)
        Returns the value of the given calendar field. This method does not involve normalization or validation of the field value.
        Parameters:
        field - the given calendar field.
        Returns:
        the value for the given calendar field.
        See Also:
        get(int)
      • set

        public final void set​(int year,                      int month,                      int date)
        Sets the values for the calendar fieldsYEAR,MONTH, andDAY_OF_MONTH. Previous values of other calendar fields are retained. If this is not desired, callclear() first.
        Parameters:
        year - the value used to set theYEAR calendar field.
        month - the value used to set theMONTH calendar field. Month value is 0-based. e.g., 0 for January.
        date - the value used to set theDAY_OF_MONTH calendar field.
        See Also:
        set(int,int),set(int,int,int,int,int),set(int,int,int,int,int,int)
      • set

        public final void set​(int year,                      int month,                      int date,                      int hourOfDay,                      int minute)
        Sets the values for the calendar fieldsYEAR,MONTH,DAY_OF_MONTH,HOUR_OF_DAY, andMINUTE. Previous values of other fields are retained. If this is not desired, callclear() first.
        Parameters:
        year - the value used to set theYEAR calendar field.
        month - the value used to set theMONTH calendar field. Month value is 0-based. e.g., 0 for January.
        date - the value used to set theDAY_OF_MONTH calendar field.
        hourOfDay - the value used to set theHOUR_OF_DAY calendar field.
        minute - the value used to set theMINUTE calendar field.
        See Also:
        set(int,int),set(int,int,int),set(int,int,int,int,int,int)
      • set

        public final void set​(int year,                      int month,                      int date,                      int hourOfDay,                      int minute,                      int second)
        Sets the values for the fieldsYEAR,MONTH,DAY_OF_MONTH,HOUR_OF_DAY,MINUTE, andSECOND. Previous values of other fields are retained. If this is not desired, callclear() first.
        Parameters:
        year - the value used to set theYEAR calendar field.
        month - the value used to set theMONTH calendar field. Month value is 0-based. e.g., 0 for January.
        date - the value used to set theDAY_OF_MONTH calendar field.
        hourOfDay - the value used to set theHOUR_OF_DAY calendar field.
        minute - the value used to set theMINUTE calendar field.
        second - the value used to set theSECOND calendar field.
        See Also:
        set(int,int),set(int,int,int),set(int,int,int,int,int)
      • clear

        public final void clear()
        Sets all the calendar field values and the time value (millisecond offset from theEpoch) of thisCalendar undefined. This means thatisSet() will returnfalse for all the calendar fields, and the date and time calculations will treat the fields as if they had never been set. ACalendar implementation class may use its specific default field values for date/time calculations. For example,GregorianCalendar uses 1970 if theYEAR field value is undefined.
        See Also:
        clear(int)
      • clear

        public final void clear​(int field)
        Sets the given calendar field value and the time value (millisecond offset from theEpoch) of thisCalendar undefined. This means thatisSet(field) will returnfalse, and the date and time calculations will treat the field as if it had never been set. ACalendar implementation class may use the field's specific default value for date and time calculations.

        TheHOUR_OF_DAY,HOUR andAM_PM fields are handled independently and thethe resolution rule for the time of day is applied. Clearing one of the fields doesn't reset the hour of day value of thisCalendar. Useset(Calendar.HOUR_OF_DAY, 0) to reset the hour value.

        Parameters:
        field - the calendar field to be cleared.
        See Also:
        clear()
      • isSet

        public final boolean isSet​(int field)
        Determines if the given calendar field has a value set, including cases that the value has been set by internal fields calculations triggered by aget method call.
        Parameters:
        field - the calendar field to test
        Returns:
        true if the given calendar field has a value set;false otherwise.
      • getDisplayName

        public String getDisplayName​(int field,                             int style,Locale locale)
        Returns the string representation of the calendarfield value in the givenstyle andlocale. If no string representation is applicable,null is returned. This method callsget(field) to get the calendarfield value if the string representation is applicable to the given calendarfield.

        For example, if thisCalendar is aGregorianCalendar and its date is 2005-01-01, then the string representation of theMONTH field would be "January" in the long style in an English locale or "Jan" in the short style. However, no string representation would be available for theDAY_OF_MONTH field, and this method would returnnull.

        The default implementation supports the calendar fields for which aDateFormatSymbols has names in the givenlocale.

        Parameters:
        field - the calendar field for which the string representation is returned
        style - the style applied to the string representation; one ofSHORT_FORMAT (SHORT),SHORT_STANDALONE,LONG_FORMAT (LONG),LONG_STANDALONE,NARROW_FORMAT, orNARROW_STANDALONE.
        locale - the locale for the string representation (any calendar types specified bylocale are ignored)
        Returns:
        the string representation of the givenfield in the givenstyle, ornull if no string representation is applicable.
        Throws:
        IllegalArgumentException - iffield orstyle is invalid, or if thisCalendar is non-lenient and any of the calendar fields have invalid values
        NullPointerException - iflocale is null
        Since:
        1.6
      • getDisplayNames

        public Map<String,​Integer> getDisplayNames​(int field,                                                 int style,Locale locale)
        Returns aMap containing all names of the calendarfield in the givenstyle andlocale and their corresponding field values. For example, if thisCalendar is aGregorianCalendar, the returned map would contain "Jan" toJANUARY, "Feb" toFEBRUARY, and so on, in theshort style in an English locale.

        Narrow names may not be unique due to use of single characters, such as "S" for Sunday and Saturday. In that case narrow names are not included in the returnedMap.

        The values of other calendar fields may be taken into account to determine a set of display names. For example, if thisCalendar is a lunisolar calendar system and the year value given by theYEAR field has a leap month, this method would return month names containing the leap month name, and month names are mapped to their values specific for the year.

        The default implementation supports display names contained in aDateFormatSymbols. For example, iffield isMONTH andstyle isALL_STYLES, this method returns aMap containing all strings returned byDateFormatSymbols.getShortMonths() andDateFormatSymbols.getMonths().

        Parameters:
        field - the calendar field for which the display names are returned
        style - the style applied to the string representation; one ofSHORT_FORMAT (SHORT),SHORT_STANDALONE,LONG_FORMAT (LONG),LONG_STANDALONE,NARROW_FORMAT, orNARROW_STANDALONE
        locale - the locale for the display names
        Returns:
        aMap containing all display names instyle andlocale and their field values, ornull if no display names are defined forfield
        Throws:
        IllegalArgumentException - iffield orstyle is invalid, or if thisCalendar is non-lenient and any of the calendar fields have invalid values
        NullPointerException - iflocale is null
        Since:
        1.6
      • complete

        protected void complete()
        Fills in any unset fields in the calendar fields. First, thecomputeTime() method is called if the time value (millisecond offset from theEpoch) has not been calculated from calendar field values. Then, thecomputeFields() method is called to calculate all calendar field values.
      • getCalendarType

        public String getCalendarType()
        Returns the calendar type of thisCalendar. Calendar types are defined by theUnicode Locale Data Markup Language (LDML) specification.

        The default implementation of this method returns the class name of thisCalendar instance. Any subclasses that implement LDML-defined calendar systems should override this method to return appropriate calendar types.

        Returns:
        the LDML-defined calendar type or the class name of thisCalendar instance
        Since:
        1.8
        See Also:
        Locale extensions,Locale.Builder.setLocale(Locale),Locale.Builder.setUnicodeLocaleKeyword(String, String)
      • equals

        public boolean equals​(Object obj)
        Compares thisCalendar to the specifiedObject. The result istrue if and only if the argument is aCalendar object of the same calendar system that represents the same time value (millisecond offset from theEpoch) under the sameCalendar parameters as this object.

        TheCalendar parameters are the values represented by theisLenient,getFirstDayOfWeek,getMinimalDaysInFirstWeek andgetTimeZone methods. If there is any difference in those parameters between the twoCalendars, this method returnsfalse.

        Use thecompareTo method to compare only the time values.

        Overrides:
        equals in class Object
        Parameters:
        obj - the object to compare with.
        Returns:
        true if this object is equal toobj;false otherwise.
        See Also:
        Object.hashCode(),HashMap
      • before

        public boolean before​(Object when)
        Returns whether thisCalendar represents a time before the time represented by the specifiedObject. This method is equivalent to:
                 compareTo(when) < 0
        if and only ifwhen is aCalendar instance. Otherwise, the method returnsfalse.
        Parameters:
        when - theObject to be compared
        Returns:
        true if the time of thisCalendar is before the time represented bywhen;false otherwise.
        See Also:
        compareTo(Calendar)
      • after

        public boolean after​(Object when)
        Returns whether thisCalendar represents a time after the time represented by the specifiedObject. This method is equivalent to:
                 compareTo(when) > 0
        if and only ifwhen is aCalendar instance. Otherwise, the method returnsfalse.
        Parameters:
        when - theObject to be compared
        Returns:
        true if the time of thisCalendar is after the time represented bywhen;false otherwise.
        See Also:
        compareTo(Calendar)
      • compareTo

        public int compareTo​(Calendar anotherCalendar)
        Compares the time values (millisecond offsets from theEpoch) represented by twoCalendar objects.
        Specified by:
        compareTo in interface Comparable<Calendar>
        Parameters:
        anotherCalendar - theCalendar to be compared.
        Returns:
        the value0 if the time represented by the argument is equal to the time represented by thisCalendar; a value less than0 if the time of thisCalendar is before the time represented by the argument; and a value greater than0 if the time of thisCalendar is after the time represented by the argument.
        Throws:
        NullPointerException - if the specifiedCalendar isnull.
        IllegalArgumentException - if the time value of the specifiedCalendar object can't be obtained due to any invalid calendar values.
        Since:
        1.5
      • add

        public abstract void add​(int field,                         int amount)
        Adds or subtracts the specified amount of time to the given calendar field, based on the calendar's rules. For example, to subtract 5 days from the current time of the calendar, you can achieve it by calling:

        add(Calendar.DAY_OF_MONTH, -5).

        Parameters:
        field - the calendar field.
        amount - the amount of date or time to be added to the field.
        See Also:
        roll(int,int),set(int,int)
      • roll

        public abstract 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. For example, to roll the current date up by one day, you can achieve it by calling:

        roll(Calendar.DATE, true). When rolling on the year or Calendar.YEAR field, it will roll the year value in the range between 1 and the value returned by callinggetMaximum(Calendar.YEAR). When rolling on the month or Calendar.MONTH field, other fields like date might conflict and, need to be changed. For instance, rolling the month on the date 01/31/96 will result in 02/29/96. When rolling on the hour-in-day or Calendar.HOUR_OF_DAY field, it will roll the hour value in the range between 0 and 23, which is zero-based.

        Parameters:
        field - the time field.
        up - indicates if the value of the specified time field is to be rolled up or rolled down. Use true if rolling up, false otherwise.
        See Also:
        add(int,int),set(int,int)
      • roll

        public void roll​(int field,                 int amount)
        Adds the specified (signed) amount to the specified calendar field without changing larger fields. A negative amount means to roll down.

        NOTE: This default implementation onCalendar just repeatedly calls the version ofroll() that rolls by one unit. This may not always do the right thing. For example, if theDAY_OF_MONTH field is 31, rolling through February will leave it set to 28. TheGregorianCalendar version of this function takes care of this problem. Other subclasses should also provide overrides of this function that do the right thing.

        Parameters:
        field - the calendar field.
        amount - the signed amount to add to the calendarfield.
        Since:
        1.2
        See Also:
        roll(int,boolean),add(int,int),set(int,int)
      • setTimeZone

        public void setTimeZone​(TimeZone value)
        Sets the time zone with the given time zone value.
        Parameters:
        value - the given time zone.
      • getTimeZone

        public TimeZone getTimeZone()
        Gets the time zone.
        Returns:
        the time zone object associated with this calendar.
      • setLenient

        public void setLenient​(boolean lenient)
        Specifies whether or not date/time interpretation is to be lenient. With lenient interpretation, a date such as "February 942, 1996" will be treated as being equivalent to the 941st day after February 1, 1996. With strict (non-lenient) interpretation, such dates will cause an exception to be thrown. The default is lenient.
        Parameters:
        lenient -true if the lenient mode is to be turned on;false if it is to be turned off.
        See Also:
        isLenient(),DateFormat.setLenient(boolean)
      • isLenient

        public boolean isLenient()
        Tells whether date/time interpretation is to be lenient.
        Returns:
        true if the interpretation mode of this calendar is lenient;false otherwise.
        See Also:
        setLenient(boolean)
      • setFirstDayOfWeek

        public void setFirstDayOfWeek​(int value)
        Sets what the first day of the week is; e.g.,SUNDAY in the U.S.,MONDAY in France.
        Parameters:
        value - the given first day of the week.
        See Also:
        getFirstDayOfWeek(),getMinimalDaysInFirstWeek()
      • setMinimalDaysInFirstWeek

        public void setMinimalDaysInFirstWeek​(int value)
        Sets what the minimal days required in the first week of the year are; For example, if the first week is defined as one that contains the first day of the first month of a year, call this method with value 1. If it must be a full week, use value 7.
        Parameters:
        value - the given minimal days required in the first week of the year.
        See Also:
        getMinimalDaysInFirstWeek()
      • getMinimalDaysInFirstWeek

        public int getMinimalDaysInFirstWeek()
        Gets what the minimal days required in the first week of the year are; e.g., if the first week is defined as one that contains the first day of the first month of a year, this method returns 1. If the minimal days required must be a full week, this method returns 7.
        Returns:
        the minimal days required in the first week of the year.
        See Also:
        setMinimalDaysInFirstWeek(int)
      • isWeekDateSupported

        public boolean isWeekDateSupported()
        Returns whether thisCalendar supports week dates.

        The default implementation of this method returnsfalse.

        Returns:
        true if thisCalendar supports week dates;false otherwise.
        Since:
        1.7
        See Also:
        getWeekYear(),setWeekDate(int,int,int),getWeeksInWeekYear()
      • setWeekDate

        public void setWeekDate​(int weekYear,                        int weekOfYear,                        int dayOfWeek)
        Sets the date of thisCalendar with the given date specifiers - week year, week of year, and day of week.

        Unlike theset method, all of the calendar fields andtime values are calculated upon return.

        IfweekOfYear is out of the valid week-of-year range inweekYear, theweekYear and weekOfYear values are adjusted in lenient mode, or an IllegalArgumentException is thrown in non-lenient mode.

        The default implementation of this method throws anUnsupportedOperationException.

        Parameters:
        weekYear - the week year
        weekOfYear - the week number based onweekYear
        dayOfWeek - the day of week value: one of the constants for theDAY_OF_WEEK field:SUNDAY, ...,SATURDAY.
        Throws:
        IllegalArgumentException - if any of the given date specifiers is invalid or any of the calendar fields are inconsistent with the given date specifiers in non-lenient mode
        UnsupportedOperationException - if any week year numbering isn't supported in thisCalendar.
        Since:
        1.7
        See Also:
        isWeekDateSupported(),getFirstDayOfWeek(),getMinimalDaysInFirstWeek()
      • getMinimum

        public abstract int getMinimum​(int field)
        Returns the minimum value for the given calendar field of thisCalendar instance. The minimum value is defined as the smallest value returned by theget method for any possible time value. The minimum value depends on calendar system specific parameters of the instance.
        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 abstract int getMaximum​(int field)
        Returns the maximum value for the given calendar field of thisCalendar instance. The maximum value is defined as the largest value returned by theget method for any possible time value. The maximum value depends on calendar system specific parameters of the instance.
        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 abstract int getGreatestMinimum​(int field)
        Returns the highest minimum value for the given calendar field of thisCalendar instance. The highest minimum value is defined as the largest value returned bygetActualMinimum(int) for any possible time value. The greatest minimum value depends on calendar system specific parameters of the instance.
        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 abstract int getLeastMaximum​(int field)
        Returns the lowest maximum value for the given calendar field of thisCalendar instance. The lowest maximum value is defined as the smallest value returned bygetActualMaximum(int) for any possible time value. The least maximum value depends on calendar system specific parameters of the instance. For example, aCalendar for the Gregorian calendar system returns 28 for theDAY_OF_MONTH field, because the 28th is the last day of the shortest month of this calendar, February in a common year.
        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 the specified calendar field could have, given the time value of thisCalendar.

        The default implementation of this method uses an iterative algorithm to determine the actual minimum value for the calendar field. Subclasses should, if possible, override this with a more efficient implementation - in many cases, they can simply returngetMinimum().

        Parameters:
        field - the calendar field
        Returns:
        the minimum of the given calendar field for the time value of thisCalendar
        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 the specified calendar field could have, given the time value of thisCalendar. For example, the actual maximum value of theMONTH field is 12 in some years, and 13 in other years in the Hebrew calendar system.

        The default implementation of this method uses an iterative algorithm to determine the actual maximum value for the calendar field. Subclasses should, if possible, override this with a more efficient implementation.

        Parameters:
        field - the calendar field
        Returns:
        the maximum of the given calendar field for the time value of thisCalendar
        Since:
        1.2
        See Also:
        getMinimum(int),getMaximum(int),getGreatestMinimum(int),getLeastMaximum(int),getActualMinimum(int)
      • clone

        public Object clone()
        Creates and returns a copy of this object.
        Overrides:
        clone in class Object
        Returns:
        a copy of this object.
        See Also:
        Cloneable
      • toString

        public String toString()
        Return a string representation of this calendar. This method is intended to be used only for debugging purposes, and the format of the returned string may vary between implementations. The returned string may be empty but may not benull.
        Overrides:
        toString in class Object
        Returns:
        a string representation of this calendar.
      • toInstant

        public final Instant toInstant()
        Converts this object to anInstant.

        The conversion creates anInstant that represents the same point on the time-line as thisCalendar.

        Returns:
        the instant representing the same point on the time-line
        Since:
        1.8