DateUtil (Keikai Spreadsheet Build 5.0.0 API)

java.lang.Object
- org.zkoss.poi.ss.usermodel.DateUtil

Direct Known Subclasses:

HSSFDateUtil
```
public class DateUtil
extends Object
```
Contains methods for dealing with Excel dates.

Author:

Michael Harhen, Glen Stampoultzis (glens at apache.org), Dan Sherman (dsherman at isisph.com), Hack Kampbjorn (hak at 2mba.dk), Alex Jacoby (ajacoby at gmail.com), Pavel Krupets (pkrupets at palmtreebusiness dot com), Thies Wellpott

Field Summary

Fields
Modifier and Type	Field and Description
`static long`	`DAY_MILLISECONDS`
`static int`	`HOURS_PER_DAY`
`static int`	`MINUTES_PER_HOUR`
`static int`	`SECONDS_PER_DAY`
`static int`	`SECONDS_PER_MINUTE`

Constructor Summary

Constructors
Modifier Constructor and Description

protected DateUtil()

Constructors
Modifier	Constructor and Description
`protected`	`DateUtil()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`protected static int`	`absoluteDay(Calendar cal, boolean use1904windowing)` Given a Calendar, return the number of days since 1900/12/31.
`static double[]`	`calcLast7Days()`
`static double[]`	`calcLastMonth()`
`static double[]`	`calcLastQuarter()`
`static double[]`	`calcLastWeek()`
`static double[]`	`calcLastYear()`
`static double[]`	`calcNextMonth()`
`static double[]`	`calcNextQuarter()`
`static double[]`	`calcNextWeek()`
`static double[]`	`calcNextYear()`
`static double[]`	`calcThisMonth()`
`static double[]`	`calcThisQuarter()`
`static double[]`	`calcThisWeek()`
`static double[]`	`calcThisYear()`
`static double[]`	`calcToday()`
`static double[]`	`calcTomorrow()`
`static double[]`	`calcYearToDate()`
`static double[]`	`calcYesterday()`
`static double`	`convertTime(String timeStr)` Converts a string of format "HH:MM" or "HH:MM:SS" to its (Excel) numeric equivalent
`static double`	`getExcelDate(Calendar date, boolean use1904windowing)` Given a Date in the form of a Calendar, converts it into a double representing its internal Excel representation, which is the number of days since 1/1/1900.
`static double`	`getExcelDate(Date date)` Given a Date, converts it into a double representing its internal Excel representation, which is the number of days since 1/1/1900.
`static double`	`getExcelDate(Date date, boolean use1904windowing)` Given a Date, converts it into a double representing its internal Excel representation, which is the number of days since 1/1/1900.
`static Calendar`	`getJavaCalendar(double date, boolean use1904windowing)` Get EXCEL date as Java Calendar (with default time zone).
`static Calendar`	`getJavaCalendar(double date, boolean use1904windowing, TimeZone timeZone)` Get EXCEL date as Java Calendar with given time zone.
`static Calendar`	`getJavaCalendarUTC(double date, boolean use1904windowing)` Get EXCEL date as Java Calendar with UTC time zone.
`static Date`	`getJavaDate(double date)` Given an Excel date with using 1900 date windowing, and converts it to a java.util.Date.
`static Date`	`getJavaDate(double date, boolean use1904windowing)` Given an Excel date with either 1900 or 1904 date windowing, converts it to a java.util.Date.
`static Date`	`getJavaDate(double date, boolean use1904windowing, TimeZone tz)` Given an Excel date with either 1900 or 1904 date windowing, converts it to a java.util.Date.
`static Date`	`getJavaDate(double date, TimeZone tz)` Given an Excel date with using 1900 date windowing, and converts it to a java.util.Date.
`static boolean`	`isADateFormat(int formatIndex, String formatString)` Given a format ID and its format String, will check to see if the format represents a date format or not.
`static boolean`	`isCellDateFormatted(Cell cell)` Check if a cell contains a date Since dates are stored internally in Excel as double values we infer it is a date if it is formatted as such.
`static boolean`	`isCellInternalDateFormatted(Cell cell)` Check if a cell contains a date, checking only for internal excel date formats.
`static boolean`	`isInternalDateFormat(int format)` Given a format ID this will check whether the format represents an internal excel date format or not.
`static boolean`	`isValidExcelDate(double value)` Given a double, checks if it is a valid Excel date.
`static Date`	`parseYYYYMMDDDate(String dateStr)` Converts a string of format "YYYY/MM/DD" to its (Excel) numeric equivalent
`static void`	`setCalendar(Calendar calendar, int wholeDays, int millisecondsInDay, boolean use1904windowing)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - SECONDS_PER_MINUTE
```
public static final int SECONDS_PER_MINUTE
```
    See Also:
    
    Constant Field Values
  - MINUTES_PER_HOUR
```
public static final int MINUTES_PER_HOUR
```
    See Also:
    
    Constant Field Values
  - HOURS_PER_DAY
```
public static final int HOURS_PER_DAY
```
    See Also:
    
    Constant Field Values
  - SECONDS_PER_DAY
```
public static final int SECONDS_PER_DAY
```
    See Also:
    
    Constant Field Values
  - DAY_MILLISECONDS
```
public static final long DAY_MILLISECONDS
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - DateUtil
```
protected DateUtil()
```
- Method Detail
  - getExcelDate
```
public static double getExcelDate(Date date)
```
    Given a Date, converts it into a double representing its internal Excel representation, which is the number of days since 1/1/1900. Fractional days represent hours, minutes, and seconds.
    
    Parameters:
    
    date - the Date
    
    Returns:
    
    Excel representation of Date (-1 if error - test for error by checking for less than 0.1)
  - getExcelDate
```
public static double getExcelDate(Date date,
                                  boolean use1904windowing)
```
    Given a Date, converts it into a double representing its internal Excel representation, which is the number of days since 1/1/1900. Fractional days represent hours, minutes, and seconds.
    
    Parameters:
    
    date - the Date
    
    use1904windowing - Should 1900 or 1904 date windowing be used?
    
    Returns:
    
    Excel representation of Date (-1 if error - test for error by checking for less than 0.1)
  - getExcelDate
```
public static double getExcelDate(Calendar date,
                                  boolean use1904windowing)
```
    Given a Date in the form of a Calendar, converts it into a double representing its internal Excel representation, which is the number of days since 1/1/1900. Fractional days represent hours, minutes, and seconds.
    
    Parameters:
    
    date - the Calendar holding the date to convert
    
    use1904windowing - Should 1900 or 1904 date windowing be used?
    
    Returns:
    
    Excel representation of Date (-1 if error - test for error by checking for less than 0.1)
  - getJavaDate
```
public static Date getJavaDate(double date,
                               TimeZone tz)
```
    Given an Excel date with using 1900 date windowing, and converts it to a java.util.Date. Excel Dates and Times are stored without any timezone information. If you know (through other means) that your file uses a different TimeZone to the system default, you can use this version of the getJavaDate() method to handle it.
    
    Parameters:
    
    date - The Excel date.
    
    tz - The TimeZone to evaluate the date in
    
    Returns:
    
    Java representation of the date, or null if date is not a valid Excel date
  - getJavaDate
```
public static Date getJavaDate(double date)
```
    Given an Excel date with using 1900 date windowing, and converts it to a java.util.Date. NOTE: If the default TimeZone in Java uses Daylight Saving Time then the conversion back to an Excel date may not give the same value, that is the comparison excelDate == getExcelDate(getJavaDate(excelDate,false)) is not always true. For example if default timezone is Europe/Copenhagen, on 2004-03-28 the minute after 01:59 CET is 03:00 CEST, if the excel date represents a time between 02:00 and 03:00 then it is converted to past 03:00 summer time
    
    Parameters:
    
    date - The Excel date.
    
    Returns:
    
    Java representation of the date, or null if date is not a valid Excel date
    
    See Also:
    
    TimeZone
  - getJavaDate
```
public static Date getJavaDate(double date,
                               boolean use1904windowing,
                               TimeZone tz)
```
    Given an Excel date with either 1900 or 1904 date windowing, converts it to a java.util.Date. Excel Dates and Times are stored without any timezone information. If you know (through other means) that your file uses a different TimeZone to the system default, you can use this version of the getJavaDate() method to handle it.
    
    Parameters:
    
    date - The Excel date.
    
    tz - The TimeZone to evaluate the date in
    
    use1904windowing - true if date uses 1904 windowing, or false if using 1900 date windowing.
    
    Returns:
    
    Java representation of the date, or null if date is not a valid Excel date
  - getJavaDate
```
public static Date getJavaDate(double date,
                               boolean use1904windowing)
```
    Given an Excel date with either 1900 or 1904 date windowing, converts it to a java.util.Date. NOTE: If the default TimeZone in Java uses Daylight Saving Time then the conversion back to an Excel date may not give the same value, that is the comparison excelDate == getExcelDate(getJavaDate(excelDate,false)) is not always true. For example if default timezone is Europe/Copenhagen, on 2004-03-28 the minute after 01:59 CET is 03:00 CEST, if the excel date represents a time between 02:00 and 03:00 then it is converted to past 03:00 summer time
    
    Parameters:
    
    date - The Excel date.
    
    use1904windowing - true if date uses 1904 windowing, or false if using 1900 date windowing.
    
    Returns:
    
    Java representation of the date, or null if date is not a valid Excel date
    
    See Also:
    
    TimeZone
  - setCalendar
```
public static void setCalendar(Calendar calendar,
                               int wholeDays,
                               int millisecondsInDay,
                               boolean use1904windowing)
```
  - getJavaCalendar
```
public static Calendar getJavaCalendar(double date,
                                       boolean use1904windowing)
```
    Get EXCEL date as Java Calendar (with default time zone). This is like getJavaDate(double, boolean) but returns a Calendar object.
    
    Parameters:
    
    date - The Excel date.
    
    use1904windowing - true if date uses 1904 windowing, or false if using 1900 date windowing.
    
    Returns:
    
    Java representation of the date, or null if date is not a valid Excel date
  - getJavaCalendarUTC
```
public static Calendar getJavaCalendarUTC(double date,
                                          boolean use1904windowing)
```
    Get EXCEL date as Java Calendar with UTC time zone. This is similar to getJavaDate(double, boolean) but returns a Calendar object that has UTC as time zone, so no daylight saving hassle.
    
    Parameters:
    
    date - The Excel date.
    
    use1904windowing - true if date uses 1904 windowing, or false if using 1900 date windowing.
    
    Returns:
    
    Java representation of the date in UTC, or null if date is not a valid Excel date
  - getJavaCalendar
```
public static Calendar getJavaCalendar(double date,
                                       boolean use1904windowing,
                                       TimeZone timeZone)
```
    Get EXCEL date as Java Calendar with given time zone.
    
    Returns:
    
    Java representation of the date, or null if date is not a valid Excel date
    
    See Also:
    
    getJavaDate(double, TimeZone)
  - isADateFormat
```
public static boolean isADateFormat(int formatIndex,
                                    String formatString)
```
    Given a format ID and its format String, will check to see if the format represents a date format or not. Firstly, it will check to see if the format ID corresponds to an internal excel date format (eg most US date formats) If not, it will check to see if the format string only contains date formatting characters (ymd-/), which covers most non US date formats.
    
    Parameters:
    
    formatIndex - The index of the format, eg from ExtendedFormatRecord.getFormatIndex
    
    formatString - The format string, eg from FormatRecord.getFormatString
    
    See Also:
    
    isInternalDateFormat(int)
  - isInternalDateFormat
```
public static boolean isInternalDateFormat(int format)
```
    Given a format ID this will check whether the format represents an internal excel date format or not.
    
    See Also:
    
    isADateFormat(int, java.lang.String)
  - isCellDateFormatted
```
public static boolean isCellDateFormatted(Cell cell)
```
    Check if a cell contains a date Since dates are stored internally in Excel as double values we infer it is a date if it is formatted as such.
    
    See Also:
    
    isADateFormat(int, String), isInternalDateFormat(int)
  - isCellInternalDateFormatted
```
public static boolean isCellInternalDateFormatted(Cell cell)
```
    Check if a cell contains a date, checking only for internal excel date formats. As Excel stores a great many of its dates in "non-internal" date formats, you will not normally want to use this method.
    
    See Also:
    
    isADateFormat(int,String), isInternalDateFormat(int)
  - isValidExcelDate
```
public static boolean isValidExcelDate(double value)
```
    Given a double, checks if it is a valid Excel date.
    
    Parameters:
    
    value - the double value
    
    Returns:
    
    true if valid
  - absoluteDay
```
protected static int absoluteDay(Calendar cal,
                                 boolean use1904windowing)
```
    Given a Calendar, return the number of days since 1900/12/31.
    
    Parameters:
    
    cal - the Calendar
    
    Returns:
    
    days number of days since 1900/12/31
    
    Throws:
    
    IllegalArgumentException - if date is invalid
  - convertTime
```
public static double convertTime(String timeStr)
```
    Converts a string of format "HH:MM" or "HH:MM:SS" to its (Excel) numeric equivalent
    
    Returns:
    
    a double between 0 and 1 representing the fraction of the day
  - parseYYYYMMDDDate
```
public static Date parseYYYYMMDDDate(String dateStr)
```
    Converts a string of format "YYYY/MM/DD" to its (Excel) numeric equivalent
    
    Returns:
    
    a double representing the (integer) number of days since the start of the Excel epoch
  - calcToday
```
public static double[] calcToday()
```
  - calcTomorrow
```
public static double[] calcTomorrow()
```
  - calcYesterday
```
public static double[] calcYesterday()
```
  - calcThisMonth
```
public static double[] calcThisMonth()
```
  - calcNextMonth
```
public static double[] calcNextMonth()
```
  - calcLastMonth
```
public static double[] calcLastMonth()
```
  - calcThisQuarter
```
public static double[] calcThisQuarter()
```
  - calcNextQuarter
```
public static double[] calcNextQuarter()
```
  - calcLastQuarter
```
public static double[] calcLastQuarter()
```
  - calcThisYear
```
public static double[] calcThisYear()
```
  - calcNextYear
```
public static double[] calcNextYear()
```
  - calcLastYear
```
public static double[] calcLastYear()
```
  - calcThisWeek
```
public static double[] calcThisWeek()
```
  - calcNextWeek
```
public static double[] calcNextWeek()
```
  - calcLastWeek
```
public static double[] calcLastWeek()
```
  - calcYearToDate
```
public static double[] calcYearToDate()
```
  - calcLast7Days
```
public static double[] calcLast7Days()
```

Class DateUtil

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

SECONDS_PER_MINUTE

MINUTES_PER_HOUR

HOURS_PER_DAY

SECONDS_PER_DAY

DAY_MILLISECONDS

Constructor Detail

DateUtil

Method Detail

getExcelDate

getExcelDate

getExcelDate

getJavaDate

getJavaDate

getJavaDate

getJavaDate

setCalendar

getJavaCalendar

getJavaCalendarUTC

getJavaCalendar

isADateFormat

isInternalDateFormat

isCellDateFormatted

isCellInternalDateFormatted

isValidExcelDate

absoluteDay

convertTime

parseYYYYMMDDDate

calcToday

calcTomorrow

calcYesterday

calcThisMonth

calcNextMonth

calcLastMonth

calcThisQuarter

calcNextQuarter

calcLastQuarter

calcThisYear

calcNextYear

calcLastYear

calcThisWeek

calcNextWeek

calcLastWeek

calcYearToDate

calcLast7Days