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## java.util
Class Calendar

    java.lang.Object
      java.util.Calendar

Direct Known Subclasses:
  CalendarImpl

    public abstract class Calendar

extends Object

`Calendar` is an abstract base class for converting between a `Date` object and a set of integer fields such as `YEAR`, `MONTH`, `DAY`, `HOUR`, and so on. (A `Date` object represents a specific instant in time with millisecond precision. See `Date` for information about the `Date` class.)

Subclasses of `Calendar` interpret a `Date` according to the rules of a specific calendar system.

Like other locale-sensitive classes, `Calendar` provides a class method, `getInstance`, for getting a generally useful object of this type.

>      Calendar rightNow = Calendar.getInstance();

A `Calendar` object can produce all the time field values needed to implement the date-time formatting for a particular language and calendar style (for example, Japanese-Gregorian, Japanese-Traditional).

When computing a `Date` from time fields, there may be insufficient information to compute the `Date` (such as only year and month but no day in the month).

Insufficient information. The calendar will use default information to specify the missing fields. This may vary by calendar; for the Gregorian calendar, the default for a field is the same as that of the start of the epoch: i.e., YEAR = 1970, MONTH = JANUARY, DATE = 1, etc. Note: The ambiguity in interpretation of what day midnight belongs to, is resolved as so: midnight "belongs" to the following day.
23:59 on Dec 31, 1969 < 00:00 on Jan 1, 1970.
12:00 PM is midday, and 12:00 AM is midnight.
11:59 PM on Jan 1 < 12:00 AM on Jan 2 < 12:01 AM on Jan 2.
11:59 AM on Mar 10 < 12:00 PM on Mar 10 < 12:01 PM on Mar 10.
24:00 or greater are invalid. Hours greater than 12 are invalid in AM/PM mode. Setting the time will never change the date.

If equivalent times are entered in AM/PM or 24 hour mode, equality will be determined by the actual time rather than the entered time.

This class has been subset for J2ME based on the JDK 1.3 Calendar class. Many methods and variables have been pruned, and other methods simplified, in an effort to reduce the size of this class.

Version:
  CLDC 1.1 02/01/2002 (based on JDK 1.3)
See Also:
  `Date`, `TimeZone`

Field Summary
`static int` | `AM` Value of the `AM_PM` field indicating the period of the day from midnight to just before noon.
`static int` | `AM_PM` Field number for `get` and `set` indicating whether the `HOUR` is before or after noon.
`static int` | `APRIL` Value of the `MONTH` field indicating the fourth month of the year.
`static int` | `AUGUST` Value of the `MONTH` field indicating the eighth month of the year.
`static int` | `DATE` Field number for `get` and `set` indicating the day of the month.
`static int` | `DAY_OF_MONTH` Field number for `get` and `set` indicating the day of the month.
`static int` | `DAY_OF_WEEK` Field number for `get` and `set` indicating the day of the week.
`static int` | `DECEMBER` Value of the `MONTH` field indicating the twelfth month of the year.
`static int` | `FEBRUARY` Value of the `MONTH` field indicating the second month of the year.
`protected int[]` | `fields` The field values for the currently set time for this calendar.
`static int` | `FRIDAY` Value of the `DAY_OF_WEEK` field indicating Friday.
`static int` | `HOUR` Field number for `get` and `set` indicating the hour of the morning or afternoon.
`static int` | `HOUR_OF_DAY` Field number for `get` and `set` indicating the hour of the day.
`protected boolean[]` | `isSet` The flags which tell if a specified time field for the calendar is set.
`static int` | `JANUARY` Value of the `MONTH` field indicating the first month of the year.
`static int` | `JULY` Value of the `MONTH` field indicating the seventh month of the year.
`static int` | `JUNE` Value of the `MONTH` field indicating the sixth month of the year.
`static int` | `MARCH` Value of the `MONTH` field indicating the third month of the year.
`static int` | `MAY` Value of the `MONTH` field indicating the fifth month of the year.
`static int` | `MILLISECOND` Field number for `get` and `set` indicating the millisecond within the second.
`static int` | `MINUTE` Field number for `get` and `set` indicating the minute within the hour.
`static int` | `MONDAY` Value of the `DAY_OF_WEEK` field indicating Monday.
`static int` | `MONTH` Field number for `get` and `set` indicating the month.
`static int` | `NOVEMBER` Value of the `MONTH` field indicating the eleventh month of the year.
`static int` | `OCTOBER` Value of the `MONTH` field indicating the tenth month of the year.
`static int` | `PM` Value of the `AM_PM` field indicating the period of the day from noon to just before midnight.
`static int` | `SATURDAY` Value of the `DAY_OF_WEEK` field indicating Saturday.
`static int` | `SECOND` Field number for `get` and `set` indicating the second within the minute.
`static int` | `SEPTEMBER` Value of the `MONTH` field indicating the ninth month of the year.
`static int` | `SUNDAY` Value of the `DAY_OF_WEEK` field indicating Sunday.
`static int` | `THURSDAY` Value of the `DAY_OF_WEEK` field indicating Thursday.
`protected long` | `time` The currently set time for this calendar, expressed in milliseconds after January 1, 1970, 0:00:00 GMT.
`static int` | `TUESDAY` Value of the `DAY_OF_WEEK` field indicating Tuesday.
`static int` | `WEDNESDAY` Value of the `DAY_OF_WEEK` field indicating Wednesday.
`static int` | `YEAR` Field number for `get` and `set` indicating the year.

Constructor Summary
`protected` | `Calendar()` Constructs a Calendar with the default time zone.

Method Summary
`boolean` | `after(Object when)` Compares the time field records.
`boolean` | `before(Object when)` Compares the time field records.
`protected abstract void` | `computeFields()` Converts the current millisecond time value `time` to field values in `fields[]`.
`protected abstract void` | `computeTime()` Converts the current field values in `fields[]` to the millisecond time value `time`.
`boolean` | `equals(Object obj)` Compares this calendar to the specified object.
`int` | `get(int field)` Gets the value for a given time field.
`static Calendar` | `getInstance()` Gets a calendar using the default time zone.
`static Calendar` | `getInstance(TimeZone zone)` Gets a calendar using the specified time zone.
`Date` | `getTime()` Gets this Calendar's current time.
`protected long` | `getTimeInMillis()` Gets this Calendar's current time as a long expressed in milliseconds after January 1, 1970, 0:00:00 GMT (the epoch).
`TimeZone` | `getTimeZone()` Gets the time zone.
`void` | `set(int field, int value)` Sets the time field with the given value.
`void` | `setTime(Date date)` Sets this Calendar's current time with the given Date.
`protected void` | `setTimeInMillis(long millis)` Sets this Calendar's current time from the given long value.
`void` | `setTimeZone(TimeZone value)` Sets the time zone with the given time zone value.

Methods inherited from class java.lang.Object
`getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

### YEAR

    public static final int YEAR

  Field number for `get` and `set` indicating the year. This is a calendar-specific value.

  See Also:
    Constant Field Values

### MONTH

    public static final int MONTH

  Field number for `get` and `set` indicating the month. This is a calendar-specific value.

  See Also:
    Constant Field Values

### DATE

    public static final int DATE

  Field number for `get` and `set` indicating the day of the month. This is a synonym for `DAY_OF_MONTH`.

  See Also:
    `DAY_OF_MONTH`, Constant Field Values

### DAY_OF_MONTH

    public static final int DAY_OF_MONTH

  Field number for `get` and `set` indicating the day of the month. This is a synonym for `DATE`.

  See Also:
    `DATE`, Constant Field Values

### DAY_OF_WEEK

    public static final int DAY_OF_WEEK

  Field number for `get` and `set` indicating the day of the week.

  See Also:
    Constant Field Values

### AM_PM

    public static final int AM_PM

  Field number for `get` and `set` indicating whether the `HOUR` is before or after noon. E.g., at 10:04:15.250 PM the `AM_PM` is `PM`.

  See Also:
    `AM`, `PM`, `HOUR`, Constant Field Values

### HOUR

    public static final int HOUR

  Field number for `get` and `set` indicating the hour of the morning or afternoon. `HOUR` is used for the 12-hour clock. E.g., at 10:04:15.250 PM the `HOUR` is 10.

  See Also:
    `AM_PM`, `HOUR_OF_DAY`, Constant Field Values

### HOUR_OF_DAY

    public static final int HOUR_OF_DAY

  Field number for `get` and `set` indicating the hour of the day. `HOUR_OF_DAY` is used for the 24-hour clock. E.g., at 10:04:15.250 PM the `HOUR_OF_DAY` is 22.

  See Also:
    Constant Field Values

### MINUTE

    public static final int MINUTE

  Field number for `get` and `set` indicating the minute within the hour. E.g., at 10:04:15.250 PM the `MINUTE` is 4.

  See Also:
    Constant Field Values

### SECOND

    public static final int SECOND

  Field number for `get` and `set` indicating the second within the minute. E.g., at 10:04:15.250 PM the `SECOND` is 15.

  See Also:
    Constant Field Values

### MILLISECOND

    public static final int MILLISECOND

  Field number for `get` and `set` indicating the millisecond within the second. E.g., at 10:04:15.250 PM the `MILLISECOND` is 250.

  See Also:
    Constant Field Values

### SUNDAY

    public static final int SUNDAY

  Value of the `DAY_OF_WEEK` field indicating Sunday.

  See Also:
    Constant Field Values

### MONDAY

    public static final int MONDAY

  Value of the `DAY_OF_WEEK` field indicating Monday.

  See Also:
    Constant Field Values

### TUESDAY

    public static final int TUESDAY

  Value of the `DAY_OF_WEEK` field indicating Tuesday.

  See Also:
    Constant Field Values

### WEDNESDAY

    public static final int WEDNESDAY

  Value of the `DAY_OF_WEEK` field indicating Wednesday.

  See Also:
    Constant Field Values

### THURSDAY

    public static final int THURSDAY

  Value of the `DAY_OF_WEEK` field indicating Thursday.

  See Also:
    Constant Field Values

### FRIDAY

    public static final int FRIDAY

  Value of the `DAY_OF_WEEK` field indicating Friday.

  See Also:
    Constant Field Values

### SATURDAY

    public static final int SATURDAY

  Value of the `DAY_OF_WEEK` field indicating Saturday.

  See Also:
    Constant Field Values

### JANUARY

    public static final int JANUARY

  Value of the `MONTH` field indicating the first month of the year.

  See Also:
    Constant Field Values

### FEBRUARY

    public static final int FEBRUARY

  Value of the `MONTH` field indicating the second month of the year.

  See Also:
    Constant Field Values

### MARCH

    public static final int MARCH

  Value of the `MONTH` field indicating the third month of the year.

  See Also:
    Constant Field Values

### APRIL

    public static final int APRIL

  Value of the `MONTH` field indicating the fourth month of the year.

  See Also:
    Constant Field Values

### MAY

    public static final int MAY

  Value of the `MONTH` field indicating the fifth month of the year.

  See Also:
    Constant Field Values

### JUNE

    public static final int JUNE

  Value of the `MONTH` field indicating the sixth month of the year.

  See Also:
    Constant Field Values

### JULY

    public static final int JULY

  Value of the `MONTH` field indicating the seventh month of the year.

  See Also:
    Constant Field Values

### AUGUST

    public static final int AUGUST

  Value of the `MONTH` field indicating the eighth month of the year.

  See Also:
    Constant Field Values

### SEPTEMBER

    public static final int SEPTEMBER

  Value of the `MONTH` field indicating the ninth month of the year.

  See Also:
    Constant Field Values

### OCTOBER

    public static final int OCTOBER

  Value of the `MONTH` field indicating the tenth month of the year.

  See Also:
    Constant Field Values

### NOVEMBER

    public static final int NOVEMBER

  Value of the `MONTH` field indicating the eleventh month of the year.

  See Also:
    Constant Field Values

### DECEMBER

    public static final int DECEMBER

  Value of the `MONTH` field indicating the twelfth month of the year.

  See Also:
    Constant Field Values

### AM

    public static final int AM

  Value of the `AM_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 the `AM_PM` field indicating the period of the day from noon to just before midnight.

  See Also:
    Constant Field Values

### fields

    protected int[] fields

  The field values for the currently set time for this calendar.

### isSet

    protected boolean[] isSet

  The flags which tell if a specified time field for the calendar is set. This is an array of `FIELD_COUNT` booleans,

### time

    protected long time

  The currently set time for this calendar, expressed in milliseconds after January 1, 1970, 0:00:00 GMT.

Constructor Detail

### Calendar

    protected Calendar()

  Constructs a Calendar with the default time zone.

  See Also:
    `TimeZone.getDefault()`

Method Detail

### getTime

    public final Date getTime()

  Gets this Calendar's current time.

  Returns:
    the current time.
  See Also:
    `setTime(java.util.Date)`

### setTime

    public final void setTime(Date date)

  Sets this Calendar's current time with the given Date.

  Note: Calling `setTime()` with `Date(Long.MAX_VALUE)` or `Date(Long.MIN_VALUE)` may yield incorrect field values from `get()`.

  Parameters:
    `date` - the given Date.
  See Also:
    `getTime()`

### getInstance

    public static Calendar getInstance()

  Gets a calendar using the default time zone.

  Returns:
    a Calendar.

### getInstance

    public static Calendar getInstance(TimeZone zone)

  Gets a calendar using the specified time zone.

  Parameters:
    `zone` - the time zone to use
  Returns:
    a Calendar.

### getTimeInMillis

    protected long getTimeInMillis()

  Gets this Calendar's current time as a long expressed in milliseconds after January 1, 1970, 0:00:00 GMT (the epoch).

  Returns:
    the current time as UTC milliseconds from the epoch.
  See Also:
    `setTimeInMillis(long)`

### setTimeInMillis

    protected 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:
    `getTimeInMillis()`

### get

    public final int get(int field)

  Gets the value for a given time field.

  Parameters:
    `field` - the given time field (either YEAR, MONTH, DATE, DAY_OF_WEEK, HOUR_OF_DAY, HOUR, AM_PM, MINUTE, SECOND, or MILLISECOND
  Returns:
    the value for the given time field.
  Throws:
    `ArrayIndexOutOfBoundsException` - if the parameter is not one of the above.

### set

    public final void set(int field,
                          int value)

  Sets the time field with the given value.

  Parameters:
    `field` - the given time field.
    `value` - the value to be set for the given time field.
  Throws:
    `ArrayIndexOutOfBoundsException` - if an illegal field parameter is received.

### equals

    public boolean equals(Object obj)

  Compares this calendar to the specified object. The result is `true` if and only if the argument is not `null` and is a `Calendar` object that represents the same calendar as this object.

  Overrides:
    `equals` in class `Object`
  Parameters:
    `obj` - the object to compare with.
  Returns:
    `true` if the objects are the same; `false` otherwise.
  See Also:
    `Boolean.hashCode()`, `Hashtable`

### before

    public boolean before(Object when)

  Compares the time field records. Equivalent to comparing result of conversion to UTC.

  Parameters:
    `when` - the Calendar to be compared with this Calendar.
  Returns:
    true if the current time of this Calendar is before the time of Calendar when; false otherwise.

### after

    public boolean after(Object when)

  Compares the time field records. Equivalent to comparing result of conversion to UTC.

  Parameters:
    `when` - the Calendar to be compared with this Calendar.
  Returns:
    true if the current time of this Calendar is after the time of Calendar when; false otherwise.

### setTimeZone

    public void setTimeZone(TimeZone value)

  Sets the time zone with the given time zone value.

  Parameters:
    `value` - the given time zone.
  See Also:
    `getTimeZone()`

### getTimeZone

    public TimeZone getTimeZone()

  Gets the time zone.

  Returns:
    the time zone object associated with this calendar.
  See Also:
    `setTimeZone(java.util.TimeZone)`

### computeFields

    protected abstract void computeFields()

  Converts the current millisecond time value `time` to field values in `fields[]`. This allows you to sync up the time field values with a new time that is set for the calendar.

### computeTime

    protected abstract void computeTime()

  Converts the current field values in `fields[]` to the millisecond time value `time`.

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