ucar.unidata.util
Class DateUtil

java.lang.Object
  ucar.unidata.util.DateUtil

public class DateUtil
extends java.lang.Object

A set of date oriented utilities

Since:

May 4, 2007 1:01:53 PM

Author:

edavis and the IDV development team

Field Summary

static java.lang.String[]	DATE_FORMATS A set of date formats
static java.lang.String[]	DATE_PATTERNS a set of regular expressions that go along with the below DATE_FORMATS
static long	MILLIS milliseconds in a millisecond
static long	MILLIS_CENTURY milliseconds in a century (approximately)
static long	MILLIS_DAY milliseconds in a day
static long	MILLIS_DECADE milliseconds in a decade (approximately)
static long	MILLIS_HOUR milliseconds in an hour
static long	MILLIS_MILLENIUM milliseconds in a century (approximately)
static long	MILLIS_MINUTE milliseconds in a minute
static long	MILLIS_MONTH milliseconds in a month (approximately)
static long	MILLIS_SECOND milliseconds in a second
static long	MILLIS_WEEK milliseconds in a week
static long	MILLIS_YEAR milliseconds in a year (approximately)
static java.lang.String[]	MONTH_NAMES _more_
static java.util.TimeZone	TIMEZONE_GMT timezone
static java.util.TimeZone	TIMEZONE_UTC _more_

Constructor Summary

DateUtil()

Method Summary

static long	daysToMillis(double days) utility to convert a given number of days to milliseconds
static java.util.Date	decodeWMODate(java.lang.String wmoDate, java.util.Date baseDate) Decode a date from a WMO header of the form ddHHmm.
static java.text.SimpleDateFormat	findFormatter(java.lang.String dateString) This finds the SDF to use for the given date string
static java.lang.String	getCurrentSystemTimeAsISO8601() format current time
static java.util.Date[]	getDateRange(java.lang.String fromDate, java.lang.String toDate, java.util.Date dflt) This gets a date range based on the text dates.
static java.text.SimpleDateFormat[]	getFormatters() _more_
static java.util.Date	getRelativeDate(java.util.Date from, java.lang.String relativeTimeString) Get a new date relative to the given date.
static java.lang.String	getTimeAsISO8601(java.util.Date date) format time
static java.lang.String	getTimeAsISO8601(long time) format time
static long	hoursToMillis(double hour) utility to convert a given number of hours to milliseconds
static void	main(java.lang.String[] args) main
static java.util.Date	max(java.util.Date date1, java.util.Date date2) Get the maximum of the 2 dates
static double	millisToHours(double millis) _more_
static double	millisToMinutes(double millis) utility to convert a given number of milliseconds to minutes
static java.util.Date	min(java.util.Date date1, java.util.Date date2) Get the minimum of the 2 dates
static long	minutesToMillis(double minutes) utility to convert a given number of minutes to milliseconds
static java.util.Date	parse(java.lang.String s) Parse the date string
static java.util.Date	parseRelative(java.util.Date baseDate, java.lang.String s, int roundDays) parse the date string (s) (e.g., -1 hour) that is relative to the given baseDate
static long	parseRelativeTimeString(java.lang.String relativeTimeString) Return the delta number of milliseconds specified in the relative time string
static java.util.Date	roundByDay(java.util.Date dttm, int day) Rounds up or down (if negative) the number of days.
static double[]	toSeconds(java.lang.String[] s) parse the array of date strings and returns the date as seconds

Methods inherited from class java.lang.Object

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

Field Detail

MONTH_NAMES

public static final java.lang.String[] MONTH_NAMES

_more_

MILLIS

public static final long MILLIS

milliseconds in a millisecond

See Also:

Constant Field Values

MILLIS_SECOND

public static final long MILLIS_SECOND

milliseconds in a second

See Also:

Constant Field Values

MILLIS_MINUTE

public static final long MILLIS_MINUTE

milliseconds in a minute

See Also:

Constant Field Values

MILLIS_HOUR

public static final long MILLIS_HOUR

milliseconds in an hour

See Also:

Constant Field Values

MILLIS_DAY

public static final long MILLIS_DAY

milliseconds in a day

See Also:

Constant Field Values

MILLIS_WEEK

public static final long MILLIS_WEEK

milliseconds in a week

See Also:

Constant Field Values

MILLIS_MONTH

public static final long MILLIS_MONTH

milliseconds in a month (approximately)

See Also:

Constant Field Values

MILLIS_YEAR

public static final long MILLIS_YEAR

milliseconds in a year (approximately)

See Also:

Constant Field Values

MILLIS_DECADE

public static final long MILLIS_DECADE

milliseconds in a decade (approximately)

See Also:

Constant Field Values

MILLIS_CENTURY

public static final long MILLIS_CENTURY

milliseconds in a century (approximately)

See Also:

Constant Field Values

MILLIS_MILLENIUM

public static final long MILLIS_MILLENIUM

milliseconds in a century (approximately)

See Also:

Constant Field Values

TIMEZONE_GMT

public static final java.util.TimeZone TIMEZONE_GMT

timezone

TIMEZONE_UTC

public static final java.util.TimeZone TIMEZONE_UTC

_more_

DATE_PATTERNS

public static final java.lang.String[] DATE_PATTERNS

a set of regular expressions that go along with the below DATE_FORMATS

DATE_FORMATS

public static final java.lang.String[] DATE_FORMATS

A set of date formats

Constructor Detail

DateUtil

public DateUtil()

Method Detail

getCurrentSystemTimeAsISO8601

public static java.lang.String getCurrentSystemTimeAsISO8601()

format current time

Returns:

current time formatted

getTimeAsISO8601

public static java.lang.String getTimeAsISO8601(java.util.Date date)

format time

Parameters:

date - date

Returns:

formatted time

min

public static java.util.Date min(java.util.Date date1,
                                 java.util.Date date2)

Get the minimum of the 2 dates

Parameters:

date1 - date1

date2 - date2

Returns:

The minimum of the 2 dates

max

public static java.util.Date max(java.util.Date date1,
                                 java.util.Date date2)

Get the maximum of the 2 dates

Parameters:

date1 - date1

date2 - date2

Returns:

The maximum of the 2 dates

getTimeAsISO8601

public static java.lang.String getTimeAsISO8601(long time)

format time

Parameters:

time - time

Returns:

formatted time

roundByDay

public static java.util.Date roundByDay(java.util.Date dttm,
                                        int day)

Rounds up or down (if negative) the number of days.

Parameters:

dttm - date to round

day - number of days

Returns:

rounded date.

getFormatters

public static java.text.SimpleDateFormat[] getFormatters()

_more_

Returns:

_more_

findFormatter

public static java.text.SimpleDateFormat findFormatter(java.lang.String dateString)

This finds the SDF to use for the given date string

Parameters:

dateString - example date

Returns:

formatter to use

getDateRange

public static java.util.Date[] getDateRange(java.lang.String fromDate,
                                            java.lang.String toDate,
                                            java.util.Date dflt)
                                     throws java.text.ParseException

This gets a date range based on the text dates. The incoming dates can be of the form:

 absolute date
 now (for current time)
 relative date (e.g., (offset unit), -5 seconds, +2 hours, +5 days, -3 weeks, -1 month
 This is calculated relative to the other date, e.g:
 -1 hour, now

 

Parameters:

fromDate - from date

toDate - to date

dflt - base default date

Returns:

date range

Throws:

java.text.ParseException - On badness

parseRelative

public static java.util.Date parseRelative(java.util.Date baseDate,
                                           java.lang.String s,
                                           int roundDays)
                                    throws java.text.ParseException

parse the date string (s) (e.g., -1 hour) that is relative to the given baseDate

Parameters:

baseDate - base date

s - date string

roundDays - round down or up the given number of days

Returns:

date

Throws:

java.text.ParseException - on badness

parse

public static java.util.Date parse(java.lang.String s)
                            throws java.text.ParseException

Parse the date string

Parameters:

s - date string

Returns:

date

Throws:

java.text.ParseException - on badness

toSeconds

public static double[] toSeconds(java.lang.String[] s)
                          throws java.text.ParseException

parse the array of date strings and returns the date as seconds

Parameters:

s - array of date strings

Returns:

array of seconds

Throws:

java.text.ParseException - On badness

daysToMillis

public static long daysToMillis(double days)

utility to convert a given number of days to milliseconds

Parameters:

days - days

Returns:

milliseconds

hoursToMillis

public static long hoursToMillis(double hour)

utility to convert a given number of hours to milliseconds

Parameters:

hour - hours

Returns:

milliseconds

millisToMinutes

public static double millisToMinutes(double millis)

utility to convert a given number of milliseconds to minutes

Parameters:

millis - milliseconds

Returns:

minutes

millisToHours

public static double millisToHours(double millis)

_more_

Parameters:

millis - _more_

Returns:

_more_

minutesToMillis

public static long minutesToMillis(double minutes)

utility to convert a given number of minutes to milliseconds

Parameters:

minutes - minutes

Returns:

milliseconds

getRelativeDate

public static java.util.Date getRelativeDate(java.util.Date from,
                                             java.lang.String relativeTimeString)

Get a new date relative to the given date.

Parameters:

from - base date

relativeTimeString - Relative time string, e.g., -1 hour

Returns:

new date

parseRelativeTimeString

public static long parseRelativeTimeString(java.lang.String relativeTimeString)

Return the delta number of milliseconds specified in the relative time string

Parameters:

relativeTimeString - This is of the form "offset unit", e.g.:

 -1 hour
 +2 weeks
 etc.
 

Returns:

milliseconds

decodeWMODate

public static java.util.Date decodeWMODate(java.lang.String wmoDate,
                                           java.util.Date baseDate)

Decode a date from a WMO header of the form ddHHmm.

Parameters:

wmoDate - WMO header string

baseDate - base date to get the year and month

Returns:

the date that is represented by wmoDate

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

main

Parameters:

args - args

Throws:

java.lang.Exception - On badness