Class DateTool

java.lang.Object
org.apache.velocity.tools.generic.SafeConfig
org.apache.velocity.tools.generic.LocaleConfig
org.apache.velocity.tools.generic.FormatConfig
org.apache.velocity.tools.generic.DateTool
All Implemented Interfaces:
Serializable
Direct Known Subclasses:
ComparisonDateTool
@DefaultKey("date") public class DateTool extends FormatConfig implements Serializable

Tool for working with Date and Calendar in Velocity templates. It is useful for accessing and formatting the "current" date as well as for formatting arbitrary Date and Calendar objects. Also the tool can be used to retrieve DateFormat instances or make conversions to and from various date types.

Possible formats include:

  • 'short', 'medium', 'long', 'full' (from DateFormat, optionally suffixed by '_date' or '_time' to get a date-only or time-only format
  • 'iso' for extended ISO 8601 without time zone (ex: '2016-11-24T10:27:30'), optionally suffixed by '_date' or '_time' to get a date-only or time-only format
  • 'iso_tz', like 'iso' with time zone offset (ex: '2016-11-24T10:27:30+01:00'), optionally suffixed by '_time' to get a time-only format ('10:27:30+01:00')
  • 'intl', like 'iso' but with a space separator between date and time (ex: '2016-11-24 10:27:30'), optionally suffixed by '_date' or '_time' to get a date-only or time-only format
  • 'intl_tz', like 'intl' but with the time zone short id suffixed after another space (ex: '2016-11-24 10:27:30 CET'), optionally suffixed by '_time' to get a time-only format ('10:27:30+01:00')
  • a custom format, as specified in SimpleDateFormat

Example of formatting the "current" date:

 $date                         -> Oct 19, 2003 9:54:50 PM
 $date.long                    -> October 19, 2003 9:54:50 PM PDT
 $date.medium_time             -> 9:54:50 PM
 $date.full_date               -> Sunday, October 19, 2003
 $date.get('default','short')  -> Oct 19, 2003 9:54 PM
 $date.get('yyyy-M-d H:m:s')   -> 2003-10-19 21:54:50
 $date.iso                     -> 2003-10-19T21:54:50-07:00
 $date.iso_tz_time             -> 21:54:50-07:00
 $date.intl_tz                 -> 2003-10-19 21:54:50 CET

Example of formatting an arbitrary date:
 $myDate                        -> Tue Oct 07 03:14:50 PDT 2003
 $date.format('medium',$myDate) -> Oct 7, 2003 3:14:50 AM

Example tools.xml config (if you want to use this with VelocityView):
<tools>
  <toolbox scope="application">
    <tool class="org.apache.velocity.tools.generic.DateTool"
             format="yyyy-MM-dd"/>
  </toolbox>
</tools>

Should you need to use several formats, you can either use explicit formats by means of the toDate(format, date) method, or you can declare several date tool instances with different formats.

The methods of this tool are highly interconnected, and overriding key methods provides an easy way to create subclasses that use a non-default format, calendar, locale, or timezone.

Since:
VelocityTools 1.0
Version:
$Revision$ $Date$
Author:
Nathan Bubna
See Also:

  • Field Details

    • TIMEZONE_KEY

      public static final String TIMEZONE_KEY
      The key used for specifying a default timezone via tool configuration.
      See Also:

  • Constructor Details

    • DateTool

      public DateTool()

  • Method Details

    • configure

      protected void configure(ValueParser values)
      Does the actual configuration. This is protected, so subclasses may share the same ValueParser and call configure at any time, while preventing templates from doing so when configure(Map) is locked.
      Overrides:
      configure in class FormatConfig
      Parameters:
      values - configuration values

    • setTimeZone

      protected void setTimeZone(TimeZone timezone)
      Sets time zone
      Parameters:
      timezone - time zone

    • getSystemTime

      public static final long getSystemTime()
      Returns:
      the system's current time as the number of milliseconds elapsed since January 1, 1970, 00:00:00 GMT.

    • getSystemDate

      public static final Date getSystemDate()
      Returns:
      the system's current time as a Date

    • getSystemCalendar

      public static final Calendar getSystemCalendar()
      Returns:
      the system's current time as a Calendar

    • getTimeZone

      public TimeZone getTimeZone()
      Returns the configured TimeZone. Default value is from TimeZone.getDefault().
      Returns:
      the configured TimeZone

    • getDate

      public Date getDate()
      Returns a Date derived from the result of getCalendar()
      Returns:
      a Date derived from the result of getCalendar()

    • getCalendar

      public Calendar getCalendar()
      Returns a Calendar instance created using the timezone and locale returned by getTimeZone() and getLocale(). This allows subclasses to easily override the default locale and timezone used by this tool.

      Sub-classes may override this method to return a Calendar instance not based on the system date. Doing so will also cause the getDate(), get(String), get(String,String), and toString() methods to return dates equivalent to the Calendar returned by this method, because those methods return values derived from the result of this method.

      Returns:
      a Calendar instance created using the results of getTimeZone() and LocaleConfig.getLocale().
      See Also:

    • getYear

      public Integer getYear()
      Returns:
      the year value of the date returned by getCalendar().
      Since:
      VelocityTools 1.2

    • getYear

      public Integer getYear(Object date)
      Parameters:
      date - target date
      Returns:
      the year value of the specified date.
      Since:
      VelocityTools 1.2

    • getMonth

      public Integer getMonth()
      Returns:
      the month value of the date returned by getCalendar().
      Since:
      VelocityTools 1.2

    • getMonth

      public Integer getMonth(Object date)
      Parameters:
      date - target date
      Returns:
      the month value of the specified date.
      Since:
      VelocityTools 1.2

    • getDay

      public Integer getDay()
      Returns:
      the day (of the month) value of the date returned by getCalendar().

      NOTE: Unlike java.util.Date, this returns the day of the month. It is equivalent to Date.getDate() and Calendar.get(Calendar.DAY_OF_MONTH). We could not call this method getDate() because that already exists in this class with a different function.
      Since:
      VelocityTools 1.2

    • getDay

      public Integer getDay(Object date)
      Parameters:
      date - target date
      Returns:
      the day (of the month) value for the specified date.

      NOTE: Unlike java.util.Date, this returns the day of the month. It is equivalent to Date.getDate() and Calendar.get(Calendar.DAY_OF_MONTH). We could not call this method getDate() because that already exists in this class with a different function.
      Since:
      VelocityTools 1.2

    • getValue

      public Integer getValue(Object field)
      Parameters:
      field - target field
      Returns:
      the specified value of the date returned by getCalendar() or null if the field is invalid.
      Since:
      VelocityTools 1.2

    • getValue

      public Integer getValue(Object field, Object date)
      Parameters:
      field - the corresponding Integer value or String name of the desired value
      date - the date/calendar from which the field value will be taken
      Returns:
      the specified value of the specified date, or null if the field or date is invalid. The field may be an Integer or it may be the name of the field as a String.
      Since:
      VelocityTools 1.2

    • getValue

      public Integer getValue(int field, Object date)
      Parameters:
      field - the int for the desired field (e.g. Calendar.MONTH)
      date - the date/calendar from which the field value will be taken
      Returns:
      the specified value of the specified date, or null if the field or date is invalid.
      Since:
      VelocityTools 1.2

    • get

      public String get(String format)
      Returns a formatted string representing the date returned by getDate(). In its default implementation, this method allows you to retrieve the current date in standard formats by simply doing things like $date.medium or $date.full. If you want only the date or time portion you can specify that along with the standard formats. (e.g. $date.medium_date or $date.short_time) More complex or custom formats can be retrieved by using the full method syntax. (e.g. $date.get('E, MMMM d'))
      Parameters:
      format - the formatting instructions
      Returns:
      a formatted representation of the date returned by getDate()
      Since:
      VelocityTools 1.1
      See Also:

    • get

      public String get(String dateStyle, String timeStyle)
      Returns a formatted string representing the date and/or time given by getDate() in standard, localized patterns.
      Parameters:
      dateStyle - the style pattern for the date
      timeStyle - the style pattern for the time
      Returns:
      a formatted representation of the date returned by getDate()
      Since:
      VelocityTools 1.1
      See Also:

    • format

      public String format(Object obj)
      Converts the specified object to a date and formats it according to the pattern or style returned by FormatConfig.getFormat().
      Parameters:
      obj - the date object to be formatted
      Returns:
      the specified date formatted as a string
      Since:
      VelocityTools 1.1
      See Also:

    • format

      public String format(String format, Object obj)
      Converts the specified object to a date and returns a formatted string representing that date in the locale returned by LocaleConfig.getLocale().
      Parameters:
      format - the formatting instructions
      obj - the date object to be formatted
      Returns:
      a formatted string for this locale representing the specified date or null if the parameters are invalid
      See Also:

    • format

      public String format(String format, Object obj, Locale locale)
      Converts the specified object to a date and returns a formatted string representing that date in the specified Locale.
      Parameters:
      format - the formatting instructions
      obj - the date object to be formatted
      locale - the locale to be used when formatting
      Returns:
      the given date as a formatted string
      See Also:

    • format

      public String format(String format, Object obj, Locale locale, TimeZone timezone)
      Returns a formatted string representing the specified date, Locale, and TimeZone.

      The specified format may be a standard style pattern ('full', 'long', 'medium', 'short', or 'default') or extended style pattern ('iso', 'iso_tz', 'intl', 'intl_tz').

      You may also specify that you want only the date or time portion be appending '_date' or '_time' respectively to the standard style pattern. (e.g. 'full_date', 'long_time', 'intl_date')

      If the format fits neither of these patterns, then the output will be formatted according to the symbols defined by SimpleDateFormat. 

        Examples: "E, MMMM d" will result in "Tue, July 24"
            "EEE, M-d (H:m)" will result in "Tuesday, 7-24 (14:12)"
      Parameters:
      format - the custom or standard pattern to be used
      obj - the date to format
      locale - the Locale to format the date for
      timezone - the TimeZone to be used when formatting
      Returns:
      a formatted string representing the specified date or null if the parameters are invalid
      Since:
      VelocityTools 1.1

    • format

      public String format(String dateStyle, String timeStyle, Object obj)
      Returns the specified date as a string formatted according to the specified date and/or time styles.
      Parameters:
      dateStyle - the style pattern for the date
      timeStyle - the style pattern for the time
      obj - the date to be formatted
      Returns:
      a formatted representation of the given date
      Since:
      VelocityTools 1.1
      See Also:

    • format

      public String format(String dateStyle, String timeStyle, Object obj, Locale locale)
      Returns the specified date as a string formatted according to the specified Locale and date and/or time styles.
      Parameters:
      dateStyle - the style pattern for the date
      timeStyle - the style pattern for the time
      obj - the date to be formatted
      locale - the Locale to be used for formatting the date
      Returns:
      a formatted representation of the given date
      Since:
      VelocityTools 1.1
      See Also:

    • format

      public String format(String dateStyle, String timeStyle, Object obj, Locale locale, TimeZone timezone)
      Returns the specified date as a string formatted according to the specified Locale and date and/or time styles.
      Parameters:
      dateStyle - the style pattern for the date
      timeStyle - the style pattern for the time
      obj - the date to be formatted
      locale - the Locale to be used for formatting the date
      timezone - the TimeZone the date should be formatted for
      Returns:
      a formatted representation of the given date
      Since:
      VelocityTools 1.1
      See Also:

    • getDateFormat

      public DateFormat getDateFormat(String format, Locale locale, TimeZone timezone)
      Returns a DateFormat instance for the specified format, Locale, and TimeZone. If the format specified is a standard style pattern, then a date-time instance will be returned with both the date and time styles set to the specified style. If it is a custom format, then a customized SimpleDateFormat will be returned.
      Parameters:
      format - the custom or standard formatting pattern to be used
      locale - the Locale to be used
      timezone - the TimeZone to be used
      Returns:
      an instance of DateFormat
      Since:
      VelocityTools 1.1
      See Also:

    • getDateFormat

      public DateFormat getDateFormat(String dateStyle, String timeStyle, Locale locale, TimeZone timezone)
      Returns a DateFormat instance for the specified date style, time style, Locale, and TimeZone.
      Parameters:
      dateStyle - the date style
      timeStyle - the time style
      locale - the Locale to be used
      timezone - the TimeZone to be used
      Returns:
      an instance of DateFormat
      Since:
      VelocityTools 1.1
      See Also:

    • toDate

      public Date toDate(Object obj)
      Converts an object to an instance of Date using the format returned by FormatConfig.getFormat(),the Locale returned by LocaleConfig.getLocale(), and the TimeZone returned by getTimeZone() if the object is not already an instance of Date, Calendar, or Long.
      Parameters:
      obj - the date to convert
      Returns:
      the object as a Date or null if no conversion is possible

    • toDate

      public Date toDate(Object obj, Locale locale)
      Converts an object to an instance of Date using the format returned by FormatConfig.getFormat(),the provided Locale, and the TimeZone returned by getTimeZone() if the object is not already an instance of Date, Calendar, or Long.
      Parameters:
      obj - the date to convert
      locale - the Locale
      Returns:
      the object as a Date or null if no conversion is possible

    • toDate

      public Date toDate(Object obj, Locale locale, TimeZone timezone)
      Converts an object to an instance of Date using the format returned by FormatConfig.getFormat(),the provided Locale, and TimeZone if the object is not already an instance of Date, Calendar, or Long.
      Parameters:
      obj - the date to convert
      locale - the Locale
      timezone - - the TimeZone
      Returns:
      the object as a Date or null if no conversion is possible

    • toDate

      public Date toDate(String format, Object obj)
      Converts an object to an instance of Date using the specified format,the Locale returned by LocaleConfig.getLocale(), and the TimeZone returned by getTimeZone() if the object is not already an instance of Date, Calendar, or Long.
      Parameters:
      format - - the format the date is in
      obj - - the date to convert
      Returns:
      the object as a Date or null if no conversion is possible
      See Also:

    • toDate

      public Date toDate(String format, Object obj, Locale locale)
      Converts an object to an instance of Date using the specified format and Locale if the object is not already an instance of Date, Calendar, or Long.
      Parameters:
      format - - the format the date is in
      obj - - the date to convert
      locale - - the Locale
      Returns:
      the object as a Date or null if no conversion is possible
      See Also:

    • toDate

      public Date toDate(String format, Object obj, Locale locale, TimeZone timezone)
      Converts an object to an instance of Date using the specified format, Locale, and TimeZone if the object is not already an instance of Date, Calendar, or Long.
      Parameters:
      format - - the format the date is in
      obj - - the date to convert
      locale - - the Locale
      timezone - - the TimeZone
      Returns:
      the object as a Date or null if no conversion is possible
      See Also:

    • toCalendar

      public Calendar toCalendar(Object obj)
      Converts an object to an instance of Calendar using the format returned by FormatConfig.getFormat(), the locale returned by LocaleConfig.getLocale() and the time zone returned by getTimeZone().
      Parameters:
      obj - the date to convert
      Returns:
      the converted date
      See Also:

    • toCalendar

      public Calendar toCalendar(Object obj, Locale locale)
      Converts an object to an instance of Calendar using the provided locale, the format returned by FormatConfig.getFormat() and the time zone returned by getTimeZone().
      Parameters:
      obj - the date to convert
      locale - the locale used
      Returns:
      the converted date
      See Also:

    • toCalendar

      public Calendar toCalendar(String format, Object obj)
      Converts an object to an instance of Calendar using the provided format, the locale returned by LocaleConfig.getLocale() and the time zone returned by getTimeZone().
      Parameters:
      format - the format to use
      obj - the date to convert
      Returns:
      the converted date
      See Also:

    • toCalendar

      public Calendar toCalendar(String format, Object obj, Locale locale)
      Converts an object to an instance of Calendar using the provided format and locale, and the time zone returned by getTimeZone().
      Parameters:
      format - the provided format
      obj - the date to convert
      locale - the locale used
      Returns:
      the converted date
      See Also:

    • toCalendar

      public Calendar toCalendar(String format, Object obj, Locale locale, TimeZone timezone)
      Converts an object to an instance of Calendar using the provided format, locale and time zone.
      Parameters:
      format - the provided format
      obj - the date to convert
      locale - the locale used
      timezone - the time zone used
      Returns:
      the converted date
      See Also:

    • toLocalizedPattern

      public String toLocalizedPattern(String format, Locale locale)
      Returns a localized date format pattern for the given format. SimpleDateFormat uses patterns that are based upon English words (such as Month = M, Day = d, and Year = y). When displaying a format pattern to readers of other languages, it is appropriate to display these patterns using their localized expectations. For instance, the date pattern yyyy-MM-dd should, for French speakers appear as "aaaa-MM-jj". SimpleDateFormat.toLocalizedPattern() provides this functionality, and this method merely calls that on an appropriately-constructed SimpleDateFormat object.
      Parameters:
      format - the custom or standard pattern to convert
      locale - the Locale to format for pattern for
      Returns:
      a format string appropriate for the specified Locale
      Since:
      VelocityTools 2.0

    • toString

      public String toString()
      Overrides:
      toString in class Object
      Returns:
      the result of getDate() formatted according to the result of FormatConfig.getFormat().
      See Also: