net.fortuna.ical4j.util

Class Dates

java.lang.Object

net.fortuna.ical4j.util.Dates

public final class Dates
extends java.lang.Object

$Id$ Created on 26/06/2005 Implements a collection of utility methods relevant to date processing.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DAYS_PER_WEEK Number of days in one week.
static int	MAX_DAYS_PER_MONTH Maximum number of days per month.
static int	MAX_DAYS_PER_YEAR Maximum number of days per year.
static int	MAX_WEEKS_PER_YEAR Maximum number of weeks per year.
static long	MILLIS_PER_DAY Number of milliseconds in one day.
static long	MILLIS_PER_HOUR Number of milliseconds in one hour.
static long	MILLIS_PER_MINUTE Number of milliseconds in one minute.
static long	MILLIS_PER_SECOND Number of milliseconds in one second.
static long	MILLIS_PER_WEEK Number of milliseconds in one week.
static int	PRECISION_DAY Constant indicating precision to the day.
static int	PRECISION_SECOND Constant indicating precision to the second.

Method Summary

Modifier and Type	Method and Description
static int	getAbsMonthDay(java.util.Date date, int monthDay) Returns the absolute month day for the month specified by the supplied date.
static int	getAbsWeekNo(java.util.Date date, int weekNo) Returns the absolute week number for the year specified by the supplied date.
static int	getAbsYearDay(java.util.Date date, int yearDay) Returns the absolute year day for the year specified by the supplied date.
static java.util.Calendar	getCalendarInstance(Date date) Returns an instance of java.util.Calendar that is suitably initialised for working with the specified date.
static long	getCurrentTimeRounded() Returns the System.currentTimeMillis(), rounded to the second.
static Date	getInstance(java.util.Date date, Value type) Returns a new date instance of the specified type.
static long	round(long time, int precision) Deprecated. It is not all that useful to perform rounding without specifying an explicit timezone.
static long	round(long time, int precision, java.util.TimeZone tz) Rounds a time value to remove any precision smaller than specified.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MILLIS_PER_SECOND

public static final long MILLIS_PER_SECOND

Number of milliseconds in one second.

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Constant Field Values

MILLIS_PER_MINUTE

public static final long MILLIS_PER_MINUTE

Number of milliseconds in one minute.

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Constant Field Values

MILLIS_PER_HOUR

public static final long MILLIS_PER_HOUR

Number of milliseconds in one hour.

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Constant Field Values

MILLIS_PER_DAY

public static final long MILLIS_PER_DAY

Number of milliseconds in one day.

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Constant Field Values

MILLIS_PER_WEEK

public static final long MILLIS_PER_WEEK

Number of milliseconds in one week.

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Constant Field Values

DAYS_PER_WEEK

public static final int DAYS_PER_WEEK

Number of days in one week.

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Constant Field Values

PRECISION_SECOND

public static final int PRECISION_SECOND

Constant indicating precision to the second.

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Constant Field Values

PRECISION_DAY

public static final int PRECISION_DAY

Constant indicating precision to the day.

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Constant Field Values

MAX_WEEKS_PER_YEAR

public static final int MAX_WEEKS_PER_YEAR

Maximum number of weeks per year.

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Constant Field Values

MAX_DAYS_PER_YEAR

public static final int MAX_DAYS_PER_YEAR

Maximum number of days per year.

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Constant Field Values

MAX_DAYS_PER_MONTH

public static final int MAX_DAYS_PER_MONTH

Maximum number of days per month.

See Also:

Constant Field Values

Method Detail

getAbsWeekNo

public static int getAbsWeekNo(java.util.Date date,
                               int weekNo)

Returns the absolute week number for the year specified by the supplied date. Note that a value of zero (0) is invalid for the weekNo parameter and an IllegalArgumentException will be thrown.

Parameters:

date - a date instance representing a week of the year

weekNo - a week number offset

Returns:

the absolute week of the year for the specified offset

getAbsYearDay

public static int getAbsYearDay(java.util.Date date,
                                int yearDay)

Returns the absolute year day for the year specified by the supplied date. Note that a value of zero (0) is invalid for the yearDay parameter and an IllegalArgumentException will be thrown.

Parameters:

date - a date instance representing a day of the year

yearDay - a day of year offset

Returns:

the absolute day of month for the specified offset

getAbsMonthDay

public static int getAbsMonthDay(java.util.Date date,
                                 int monthDay)

Returns the absolute month day for the month specified by the supplied date. Note that a value of zero (0) is invalid for the monthDay parameter and an IllegalArgumentException will be thrown.

Parameters:

date - a date instance representing a day of the month

monthDay - a day of month offset

Returns:

the absolute day of month for the specified offset

getInstance

public static Date getInstance(java.util.Date date,
                               Value type)

Returns a new date instance of the specified type. If no type is specified a DateTime instance is returned.

Parameters:

date - a seed Java date instance

type - the type of date instance

Returns:

an instance of net.fortuna.ical4j.model.Date

getCalendarInstance

public static java.util.Calendar getCalendarInstance(Date date)

Returns an instance of java.util.Calendar that is suitably initialised for working with the specified date.

Parameters:

date - a date instance

Returns:

a java.util.Calendar

round

public static long round(long time,
                         int precision)

Deprecated. It is not all that useful to perform rounding without specifying an explicit timezone.

Parameters:

time - the time value to round

precision - the rounding precision

Returns:

a round time value

round

public static long round(long time,
                         int precision,
                         java.util.TimeZone tz)

Rounds a time value to remove any precision smaller than specified.

Parameters:

time - the time value to round

precision - the rounding precision

tz - the timezone of the rounded value

Returns:

a round time value

getCurrentTimeRounded

public static long getCurrentTimeRounded()

Returns the System.currentTimeMillis(), rounded to the second.

By doing a rough rounding here, we avoid an expensive java.util.Calendar based rounding later on.

Returns:

the current time in millisec.