DateUtil (Unidata IDV API v6.3)

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

Fields
Modifier and Type	Field and Description
`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

Constructors
Constructor and Description

DateUtil()

Constructors
Constructor and Description
`DateUtil()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`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 double`	`getDateTimeRangeInHours(ucar.visad.data.CalendarDateTime fromDate, ucar.visad.data.CalendarDateTime toDate)` This is calculated the hour difference between two calendardatetimes
`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
  - getDateTimeRangeInHours
```
public static double getDateTimeRangeInHours(ucar.visad.data.CalendarDateTime fromDate,
                                             ucar.visad.data.CalendarDateTime toDate)
```
    This is calculated the hour difference between two calendardatetimes
    
    Parameters:
    
    fromDate - from date
    
    toDate - to date
    
    Returns:
    
    date range

Class DateUtil

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

MONTH_NAMES

MILLIS

MILLIS_SECOND

MILLIS_MINUTE

MILLIS_HOUR

MILLIS_DAY

MILLIS_WEEK

MILLIS_MONTH

MILLIS_YEAR

MILLIS_DECADE

MILLIS_CENTURY

MILLIS_MILLENIUM

TIMEZONE_GMT

TIMEZONE_UTC

DATE_PATTERNS

DATE_FORMATS

Constructor Detail

DateUtil

Method Detail

getCurrentSystemTimeAsISO8601

getTimeAsISO8601

min

max

getTimeAsISO8601

roundByDay

getFormatters

findFormatter

getDateRange

parseRelative

parse

toSeconds

daysToMillis

hoursToMillis

millisToMinutes

millisToHours

minutesToMillis

getRelativeDate

parseRelativeTimeString

decodeWMODate

main

getDateTimeRangeInHours