com.ibm.icu.text
Class DateIntervalInfo

java.lang.Object
  com.ibm.icu.text.DateIntervalInfo

All Implemented Interfaces:

Freezable<DateIntervalInfo>, Serializable, Cloneable

public class DateIntervalInfo
extends Object
implements Cloneable, Freezable<DateIntervalInfo>, Serializable

DateIntervalInfo is a public class for encapsulating localizable date time interval patterns. It is used by DateIntervalFormat.

For most users, ordinary use of DateIntervalFormat does not need to create DateIntervalInfo object directly. DateIntervalFormat will take care of it when creating a date interval formatter when user pass in skeleton and locale.

For power users, who want to create their own date interval patterns, or want to re-set date interval patterns, they could do so by directly creating DateIntervalInfo and manupulating it.

Logically, the interval patterns are mappings from (skeleton, the_largest_different_calendar_field) to (date_interval_pattern).

A skeleton

1. only keeps the field pattern letter and ignores all other parts in a pattern, such as space, punctuations, and string literals.
2. hides the order of fields.
3. might hide a field's pattern letter length. For those non-digit calendar fields, the pattern letter length is important, such as MMM, MMMM, and MMMMM; EEE and EEEE, and the field's pattern letter length is honored. For the digit calendar fields, such as M or MM, d or dd, yy or yyyy, the field pattern length is ignored and the best match, which is defined in date time patterns, will be returned without honor the field pattern letter length in skeleton.

The calendar fields we support for interval formatting are: year, month, date, day-of-week, am-pm, hour, hour-of-day, and minute. Those calendar fields can be defined in the following order: year > month > date > am-pm > hour > minute The largest different calendar fields between 2 calendars is the first different calendar field in above order. For example: the largest different calendar fields between "Jan 10, 2007" and "Feb 20, 2008" is year.

There is a set of pre-defined static skeleton strings. There are pre-defined interval patterns for those pre-defined skeletons in locales' resource files. For example, for a skeleton YEAR_ABBR_MONTH_DAY, which is "yMMMd", in en_US, if the largest different calendar field between date1 and date2 is "year", the date interval pattern is "MMM d, yyyy - MMM d, yyyy", such as "Jan 10, 2007 - Jan 10, 2008". If the largest different calendar field between date1 and date2 is "month", the date interval pattern is "MMM d - MMM d, yyyy", such as "Jan 10 - Feb 10, 2007". If the largest different calendar field between date1 and date2 is "day", the date interval pattern is ""MMM d-d, yyyy", such as "Jan 10-20, 2007". For date skeleton, the interval patterns when year, or month, or date is different are defined in resource files. For time skeleton, the interval patterns when am/pm, or hour, or minute is different are defined in resource files.

There are 2 dates in interval pattern. For most locales, the first date in an interval pattern is the earlier date. There might be a locale in which the first date in an interval pattern is the later date. We use fallback format for the default order for the locale. For example, if the fallback format is "{0} - {1}", it means the first date in the interval pattern for this locale is earlier date. If the fallback format is "{1} - {0}", it means the first date is the later date. For a particular interval pattern, the default order can be overriden by prefixing "latestFirst:" or "earliestFirst:" to the interval pattern. For example, if the fallback format is "{0}-{1}", but for skeleton "yMMMd", the interval pattern when day is different is "latestFirst:d-d MMM yy", it means by default, the first date in interval pattern is the earlier date. But for skeleton "yMMMd", when day is different, the first date in "d-d MMM yy" is the later date.

The recommended way to create a DateIntervalFormat object is to pass in the locale. By using a Locale parameter, the DateIntervalFormat object is initialized with the pre-defined interval patterns for a given or default locale.

Users can also create DateIntervalFormat object by supplying their own interval patterns. It provides flexibility for power usage.

After a DateIntervalInfo object is created, clients may modify the interval patterns using setIntervalPattern function as so desired. Currently, users can only set interval patterns when the following calendar fields are different: ERA, YEAR, MONTH, DATE, DAY_OF_MONTH, DAY_OF_WEEK, AM_PM, HOUR, HOUR_OF_DAY, and MINUTE. Interval patterns when other calendar fields are different is not supported.

DateIntervalInfo objects are cloneable. When clients obtain a DateIntervalInfo object, they can feel free to modify it as necessary.

DateIntervalInfo are not expected to be subclassed. Data for a calendar is loaded out of resource bundles. Through ICU 4.4, date interval patterns are only supported in the Gregoria calendar; non-Gregorian calendars are supported from ICU 4.4.1.

See Also:

Serialized Form

Status:

Stable ICU 4.0.

Nested Class Summary

static class

DateIntervalInfo.PatternInfo PatternInfo class saves the first and second part of interval pattern, and whether the interval pattern is earlier date first.

Constructor Summary

DateIntervalInfo()
Deprecated. This API is ICU internal only.

DateIntervalInfo(ULocale locale)
Construct DateIntervalInfo for the given locale,

Method Summary

Object	clone() Boilerplate.
DateIntervalInfo	cloneAsThawed() Boilerplate for Freezable
boolean	equals(Object a) Override equals
DateIntervalInfo	freeze() Boilerplate for Freezable
boolean	getDefaultOrder() Get default order -- whether the first date in pattern is later date or not.
String	getFallbackIntervalPattern() Get the fallback interval pattern.
DateIntervalInfo.PatternInfo	getIntervalPattern(String skeleton, int field) Get the interval pattern given the largest different calendar field.
int	hashCode() Override hashcode
boolean	isFrozen() Boilerplate for Freezable
void	setFallbackIntervalPattern(String fallbackPattern) Re-set the fallback interval pattern.
void	setIntervalPattern(String skeleton, int lrgDiffCalUnit, String intervalPattern) Provides a way for client to build interval patterns.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DateIntervalInfo

public DateIntervalInfo()

Deprecated. This API is ICU internal only.

Create empty instance. It does not initialize any interval patterns except that it initialize default fall-back pattern as "{0} - {1}", which can be reset by setFallbackIntervalPattern(). It should be followed by setFallbackIntervalPattern() and setIntervalPattern(), and is recommended to be used only for power users who wants to create their own interval patterns and use them to create date interval formatter.

Status:

Internal. This API is ICU internal only.

DateIntervalInfo

public DateIntervalInfo(ULocale locale)

Construct DateIntervalInfo for the given locale,

Parameters:

locale - the interval patterns are loaded from the appropriate calendar data (specified calendar or default calendar) in this locale.

Status:

Stable ICU 4.0.

Method Detail

setIntervalPattern

public void setIntervalPattern(String skeleton,
                               int lrgDiffCalUnit,
                               String intervalPattern)

Provides a way for client to build interval patterns. User could construct DateIntervalInfo by providing a list of skeletons and their patterns.

For example:

 DateIntervalInfo dIntervalInfo = new DateIntervalInfo();
 dIntervalInfo.setIntervalPattern("yMd", Calendar.YEAR, "'from' yyyy-M-d 'to' yyyy-M-d"); 
 dIntervalInfo.setIntervalPattern("yMMMd", Calendar.MONTH, "'from' yyyy MMM d 'to' MMM d");
 dIntervalInfo.setIntervalPattern("yMMMd", Calendar.DAY, "yyyy MMM d-d");
 dIntervalInfo.setFallbackIntervalPattern("{0} ~ {1}");
 

Restriction: Currently, users can only set interval patterns when the following calendar fields are different: ERA, YEAR, MONTH, DATE, DAY_OF_MONTH, DAY_OF_WEEK, AM_PM, HOUR, HOUR_OF_DAY, and MINUTE. Interval patterns when other calendar fields are different are not supported.

Parameters:

skeleton - the skeleton on which interval pattern based

lrgDiffCalUnit - the largest different calendar unit.

intervalPattern - the interval pattern on the largest different calendar unit. For example, if lrgDiffCalUnit is "year", the interval pattern for en_US when year is different could be "'from' yyyy 'to' yyyy".

Throws:

IllegalArgumentException - if setting interval pattern on a calendar field that is smaller than the MINIMUM_SUPPORTED_CALENDAR_FIELD

UnsupportedOperationException - if the object is frozen

Status:

Stable ICU 4.0.

getIntervalPattern

public DateIntervalInfo.PatternInfo getIntervalPattern(String skeleton,
                                                       int field)

Get the interval pattern given the largest different calendar field.

Parameters:

skeleton - the skeleton

field - the largest different calendar field

Returns:

interval pattern return null if interval pattern is not found.

Throws:

IllegalArgumentException - if getting interval pattern on a calendar field that is smaller than the MINIMUM_SUPPORTED_CALENDAR_FIELD

Status:

Stable ICU 4.0.

getFallbackIntervalPattern

public String getFallbackIntervalPattern()

Get the fallback interval pattern.

Returns:

fallback interval pattern

Status:

Stable ICU 4.0.

setFallbackIntervalPattern

public void setFallbackIntervalPattern(String fallbackPattern)

Re-set the fallback interval pattern. In construction, default fallback pattern is set as "{0} - {1}". And constructor taking locale as parameter will set the fallback pattern as what defined in the locale resource file. This method provides a way for user to replace the fallback pattern.

Parameters:

fallbackPattern - fall-back interval pattern.

Throws:

UnsupportedOperationException - if the object is frozen

IllegalArgumentException - if there is no pattern {0} or pattern {1} in fallbakckPattern

Status:

Stable ICU 4.0.

getDefaultOrder

public boolean getDefaultOrder()

Get default order -- whether the first date in pattern is later date or not. return default date ordering in interval pattern. TRUE if the first date in pattern is later date, FALSE otherwise.

Status:

Stable ICU 4.0.

clone

public Object clone()

Boilerplate. Clone this object.

Overrides:

clone in class Object

Returns:

a copy of the object

Status:

Stable ICU4.0.

isFrozen

public boolean isFrozen()

Boilerplate for Freezable

Specified by:

isFrozen in interface Freezable<DateIntervalInfo>

Status:

Stable ICU 4.0.

freeze

public DateIntervalInfo freeze()

Boilerplate for Freezable

Specified by:

freeze in interface Freezable<DateIntervalInfo>

Returns:

the object itself.

Status:

Stable ICU 4.4.

cloneAsThawed

public DateIntervalInfo cloneAsThawed()

Boilerplate for Freezable

Specified by:

cloneAsThawed in interface Freezable<DateIntervalInfo>

Status:

Stable ICU 4.4.

equals

public boolean equals(Object a)

Override equals

Overrides:

equals in class Object

Status:

Stable ICU 4.0.

hashCode

public int hashCode()

Override hashcode

Overrides:

hashCode in class Object

Status:

Stable ICU 4.0.