DateTimePatternGenerator
public
class
DateTimePatternGenerator
extends Object
implements
Cloneable,
Freezable<DateTimePatternGenerator>
| java.lang.Object | |
| ↳ | android.icu.text.DateTimePatternGenerator |
This class provides flexible generation of date format patterns, like "yy-MM-dd". The user can build up the generator by adding successive patterns. Once that is done, a query can be made using a "skeleton", which is a pattern which just includes the desired fields and lengths. The generator will return the "best fit" pattern corresponding to that skeleton.
The main method people will use is getBestPattern(String skeleton), since normally this class is pre-built with data from a particular locale. However, generators can be built directly from other data as well.
Summary
Nested classes | |
|---|---|
class |
DateTimePatternGenerator.PatternInfo
PatternInfo supplies output parameters for addPattern(...). |
Constants | |
|---|---|
int |
DAY
|
int |
DAYPERIOD
|
int |
DAY_OF_WEEK_IN_MONTH
|
int |
DAY_OF_YEAR
|
int |
ERA
|
int |
FRACTIONAL_SECOND
|
int |
HOUR
|
int |
MATCH_ALL_FIELDS_LENGTH
Option mask for forcing the width of all date and time fields. |
int |
MATCH_HOUR_FIELD_LENGTH
Option mask for forcing the width of hour field. |
int |
MATCH_NO_OPTIONS
Default option mask used for |
int |
MINUTE
|
int |
MONTH
|
int |
QUARTER
|
int |
SECOND
|
int |
WEEKDAY
|
int |
WEEK_OF_MONTH
|
int |
WEEK_OF_YEAR
|
int |
YEAR
|
int |
ZONE
|
Protected constructors | |
|---|---|
DateTimePatternGenerator()
Only for use by subclasses |
|
Public methods | |
|---|---|
DateTimePatternGenerator
|
addPattern(String pattern, boolean override, DateTimePatternGenerator.PatternInfo returnInfo)
Adds a pattern to the generator. |
Object
|
clone()
Returns a copy of this |
DateTimePatternGenerator
|
cloneAsThawed()
Provides for the clone operation. |
DateTimePatternGenerator
|
freeze()
Freezes the object. |
String
|
getAppendItemFormat(int field)
Getter corresponding to setAppendItemFormats. |
String
|
getAppendItemName(int field)
Getter corresponding to setAppendItemName. |
String
|
getBaseSkeleton(String pattern)
Utility to return a unique base skeleton from a given pattern. |
Set<String>
|
getBaseSkeletons(Set<String> result)
Return a list of all the base skeletons (in canonical form) from this class |
String
|
getBestPattern(String skeleton, int options)
Return the best pattern matching the input skeleton. |
String
|
getBestPattern(String skeleton)
Return the best pattern matching the input skeleton. |
String
|
getDateTimeFormat()
Getter corresponding to setDateTimeFormat. |
String
|
getDateTimeFormat(int style)
Getter corresponding to setDateTimeFormat. |
String
|
getDecimal()
Getter corresponding to setDecimal. |
DateFormat.HourCycle
|
getDefaultHourCycle()
Return the default hour cycle. |
static
DateTimePatternGenerator
|
getEmptyInstance()
Create empty generator, to be constructed with addPattern(...) etc. |
String
|
getFieldDisplayName(int field, DateTimePatternGenerator.DisplayWidth width)
The general interface to get a display name for a particular date/time field, in one of several possible display widths. |
static
DateTimePatternGenerator
|
getInstance()
Construct a flexible generator according to data for the default |
static
DateTimePatternGenerator
|
getInstance(Locale locale)
Construct a flexible generator according to data for a given locale. |
static
DateTimePatternGenerator
|
getInstance(ULocale uLocale)
Construct a flexible generator according to data for a given locale. |
String
|
getSkeleton(String pattern)
Utility to return a unique skeleton from a given pattern. |
Map<String, String>
|
getSkeletons(Map<String, String> result)
Return a list of all the skeletons (in canonical form) from this class, and the patterns that they map to. |
boolean
|
isFrozen()
Determines whether the object has been frozen or not. |
String
|
replaceFieldTypes(String pattern, String skeleton)
Adjusts the field types (width and subtype) of a pattern to match what is in a skeleton. |
String
|
replaceFieldTypes(String pattern, String skeleton, int options)
Adjusts the field types (width and subtype) of a pattern to match what is in a skeleton. |
void
|
setAppendItemFormat(int field, String value)
An AppendItem format is a pattern used to append a field if there is no good match. |
void
|
setAppendItemName(int field, String value)
Sets the names of fields, eg "era" in English for ERA. |
void
|
setDateTimeFormat(String dateTimeFormat)
The date time format is a message format pattern used to compose date and time patterns. |
void
|
setDateTimeFormat(int style, String dateTimeFormat)
dateTimeFormats are message patterns used to compose combinations of date and time patterns. |
void
|
setDecimal(String decimal)
The decimal value is used in formatting fractions of seconds. |
Inherited methods | |
|---|---|
Constants
DAY_OF_WEEK_IN_MONTH
public static final int DAY_OF_WEEK_IN_MONTH
Constant Value: 9 (0x00000009)
DAY_OF_YEAR
public static final int DAY_OF_YEAR
Constant Value: 8 (0x00000008)
FRACTIONAL_SECOND
public static final int FRACTIONAL_SECOND
Constant Value: 14 (0x0000000e)
MATCH_ALL_FIELDS_LENGTH
public static final int MATCH_ALL_FIELDS_LENGTH
Option mask for forcing the width of all date and time fields.
Constant Value: 65535 (0x0000ffff)
MATCH_HOUR_FIELD_LENGTH
public static final int MATCH_HOUR_FIELD_LENGTH
Option mask for forcing the width of hour field.
Constant Value: 2048 (0x00000800)
MATCH_NO_OPTIONS
public static final int MATCH_NO_OPTIONS
Default option mask used for getBestPattern(java.lang.String, int)
and replaceFieldTypes(java.lang.String, java.lang.String, int).
Constant Value: 0 (0x00000000)
WEEK_OF_MONTH
public static final int WEEK_OF_MONTH
Constant Value: 5 (0x00000005)
WEEK_OF_YEAR
public static final int WEEK_OF_YEAR
Constant Value: 4 (0x00000004)
Protected constructors
DateTimePatternGenerator
protected DateTimePatternGenerator ()
Only for use by subclasses
Public methods
addPattern
public DateTimePatternGenerator addPattern (String pattern, boolean override, DateTimePatternGenerator.PatternInfo returnInfo)
Adds a pattern to the generator. If the pattern has the same skeleton as an existing pattern, and the override parameter is set, then the previous value is overridden. Otherwise, the previous value is retained. In either case, the conflicting information is returned in PatternInfo.
Note that single-field patterns (like "MMM") are automatically added, and don't need to be added explicitly! *
Example code:
Date date= new GregorianCalendar(1999,9,13,23,58,59).getTime();
ULocale locale = ULocale.FRANCE;
// Create an DateTimePatternGenerator instance for the given locale
DateTimePatternGenerator gen = DateTimePatternGenerator.getInstance(locale);
SimpleDateFormat format = new SimpleDateFormat(gen.getBestPattern("MMMMddHmm"), locale);
DateTimePatternGenerator.PatternInfo returnInfo = new DateTimePatternGenerator.PatternInfo();
// Add '. von' to the existing pattern
gen.addPattern("dd'. von' MMMM", true, returnInfo);
// Apply the new pattern
format.applyPattern(gen.getBestPattern("MMMMddHmm"));
System.out.println("New Pattern for FRENCH: "+format.toPattern());
System.out.println("Date Time in new Pattern: "+format.format(date));
/** output of the sample code:
**************************************************************************************************
New Pattern for FRENCH: dd. 'von' MMMM HH:mm
Date Time in new Pattern: 13. von octobre 23:58
*************************************************************************************************/| Parameters | |
|---|---|
pattern |
String: Pattern to add. |
override |
boolean: When existing values are to be overridden use true, otherwise
use false. |
returnInfo |
DateTimePatternGenerator.PatternInfo: Returned information. |
| Returns | |
|---|---|
DateTimePatternGenerator |
|
clone
public Object clone ()
Returns a copy of this DateTimePatternGenerator object.
| Returns | |
|---|---|
Object |
A copy of this DateTimePatternGenerator object. |
cloneAsThawed
public DateTimePatternGenerator cloneAsThawed ()
Provides for the clone operation. Any clone is initially unfrozen.
| Returns | |
|---|---|
DateTimePatternGenerator |
|
freeze
public DateTimePatternGenerator freeze ()
Freezes the object.
| Returns | |
|---|---|
DateTimePatternGenerator |
the object itself. |
getAppendItemFormat
public String getAppendItemFormat (int field)
Getter corresponding to setAppendItemFormats. Values below 0 or at or above TYPE_LIMIT are illegal arguments.
| Parameters | |
|---|---|
field |
int: The index to retrieve the append item formats. |
| Returns | |
|---|---|
String |
append pattern for field |
getAppendItemName
public String getAppendItemName (int field)
Getter corresponding to setAppendItemName. Values below 0 or at or above TYPE_LIMIT are illegal arguments. Note: The more general method for getting date/time field display names is getFieldDisplayName.
| Parameters | |
|---|---|
field |
int: The index to get the append item name. |
| Returns | |
|---|---|
String |
name for field |
See also:
getBaseSkeleton
public String getBaseSkeleton (String pattern)
Utility to return a unique base skeleton from a given pattern. This is the same as the skeleton, except that differences in length are minimized so as to only preserve the difference between string and numeric form. So for example, both "MMM-dd" and "d/MMM" produce the skeleton "MMMd" (notice the single d).
| Parameters | |
|---|---|
pattern |
String: Input pattern, such as "dd/MMM" |
| Returns | |
|---|---|
String |
skeleton, such as "MMMdd" |
getBaseSkeletons
public Set<String> getBaseSkeletons (Set<String> result)
Return a list of all the base skeletons (in canonical form) from this class
| Parameters | |
|---|---|
result |
Set |
| Returns | |
|---|---|
Set<String> |
|
getBestPattern
public String getBestPattern (String skeleton, int options)
Return the best pattern matching the input skeleton. It is guaranteed to have all of the fields in the skeleton.
| Parameters | |
|---|---|
skeleton |
String: The skeleton is a pattern containing only the variable fields.
For example, "MMMdd" and "mmhh" are skeletons. |
options |
int: MATCH_xxx options for forcing the length of specified fields in
the returned pattern to match those in the skeleton (when this would
not happen otherwise). For default behavior, use MATCH_NO_OPTIONS. |
| Returns | |
|---|---|
String |
Best pattern matching the input skeleton (and options). |
getBestPattern
public String getBestPattern (String skeleton)
Return the best pattern matching the input skeleton. It is guaranteed to have all of the fields in the skeleton.
Example code:
final String[] skeletons = {
"yQQQQ", // year + full name of quarter, i.e., 4th quarter 1999
"yMMMM", // year + full name of month, i.e., October 1999
"MMMMd", // full name of month + day of the month, i.e., October 25
"hhmm", // 12-hour-cycle format, i.e., 1:32 PM
"jjmm" // preferred hour format for the given locale, i.e., 24-hour-cycle format for fr_FR
};
final ULocale[] locales = {
new ULocale ("en_US"),
new ULocale ("fr_FR"),
new ULocale ("zh_CN"),
};
DateTimePatternGenerator dtfg = null;
Date date= new GregorianCalendar(1999,9,13,23,58,59).getTime();
System.out.printf("%-20s%-35s%-35s%-35s\n\n", "Skeleton", "en_US", "fr_FR","zh_CN");
for (String skeleton:skeletons) {
System.out.printf("%-20s", skeleton);
for (ULocale locale:locales) {
// create a DateTimePatternGenerator instance for given locale
dtfg = DateTimePatternGenerator.getInstance(locale);
// use getBestPattern method to get the best pattern for the given skeleton
String pattern = dtfg.getBestPattern(skeleton);
// Constructs a SimpleDateFormat with the best pattern generated above and the given locale
SimpleDateFormat sdf = new SimpleDateFormat(pattern, locale);
// Get the format of the given date
System.out.printf("%-35s",sdf.format(date));
}
System.out.println("\n");
}
/** output of the sample code:
*************************************************************************************************************
Skeleton en_US fr_FR zh_CN
yQQQQ 4th quarter 1999 4e trimestre 1999 1999年第四季度
yMMMM October 1999 octobre 1999 1999年10月
MMMMd October 13 13 octobre 10月13日
hhmm 11:58 PM 11:58 PM 下午11:58
jjmm 11:58 PM 23:58 下午11:58
**************************************************************************************************************/
// Use DateTime.getPatternInstance to produce the same Date/Time format with predefined constant field value
final String[] dtfskeleton = {
DateFormat.YEAR_QUARTER, // year + full name of quarter, i.e., 4th quarter 1999
DateFormat.YEAR_MONTH, // year + full name of month, i.e., October 1999
DateFormat.MONTH_DAY // full name of month + day of the month, i.e., October 25
};
System.out.printf("%-20s%-35s%-35s%-35s\n\n", "Skeleton", "en_US", "fr_FR","zh_CN");
for (String skeleton:dtfskeleton) {
System.out.printf("%-20s", skeleton);
for (ULocale locale:locales) {
// Use DateFormat.getPatternInstance to get the date/time format for the locale,
// and apply the format to the given date
String df=DateFormat.getPatternInstance(skeleton,locale).format(date);
System.out.printf("%-35s",df);
}
System.out.println("\n");
}
/** output of the sample code:
************************************************************************************************************
Skeleton en_US fr_FR zh_CN
yQQQQ 4th quarter 1999 4e trimestre 1999 1999年第四季度
yMMMM October 1999 octobre 1999 1999年10月
MMMMd October 13 13 octobre 10月13日
************************************************************************************************************/| Parameters | |
|---|---|
skeleton |
String: The skeleton is a pattern containing only the variable fields.
For example, "MMMdd" and "mmhh" are skeletons. |
| Returns | |
|---|---|
String |
Best pattern matching the input skeleton. |
getDateTimeFormat
public String getDateTimeFormat ()
Getter corresponding to setDateTimeFormat. There are four DateTimeFormats in a DateTimePatternGenerator object, corresponding to date styles DateFormat.FULL..DateFormat.SHORT. This method gets the style for DateFormat.MEDIUM (the default). To get them individually, see getDateTimeFormat(int style).
| Returns | |
|---|---|
String |
pattern |
getDateTimeFormat
public String getDateTimeFormat (int style)
Getter corresponding to setDateTimeFormat.
| Parameters | |
|---|---|
style |
int: one of DateFormat.FULL..DateFormat.SHORT. An exception will
be thrown if out of range. |
| Returns | |
|---|---|
String |
the current dateTimeFormat for the specified style. |
getDecimal
public String getDecimal ()
Getter corresponding to setDecimal.
| Returns | |
|---|---|
String |
string corresponding to the decimal point |
getDefaultHourCycle
public DateFormat.HourCycle getDefaultHourCycle ()
Return the default hour cycle.
| Returns | |
|---|---|
DateFormat.HourCycle |
|
getEmptyInstance
public static DateTimePatternGenerator getEmptyInstance ()
Create empty generator, to be constructed with addPattern(...) etc.
| Returns | |
|---|---|
DateTimePatternGenerator |
|
getFieldDisplayName
public String getFieldDisplayName (int field, DateTimePatternGenerator.DisplayWidth width)
The general interface to get a display name for a particular date/time field, in one of several possible display widths.
| Parameters | |
|---|---|
field |
int: The field type, such as ERA. |
width |
DateTimePatternGenerator.DisplayWidth: The desired DisplayWidth, such as DisplayWidth.ABBREVIATED. |
| Returns | |
|---|---|
String |
The display name for the field |
getInstance
public static DateTimePatternGenerator getInstance ()
Construct a flexible generator according to data for the default FORMAT locale.
| Returns | |
|---|---|
DateTimePatternGenerator |
|
See also:
getInstance
public static DateTimePatternGenerator getInstance (Locale locale)
Construct a flexible generator according to data for a given locale.
| Parameters | |
|---|---|
locale |
Locale: The Locale to pass. |
| Returns | |
|---|---|
DateTimePatternGenerator |
|
getInstance
public static DateTimePatternGenerator getInstance (ULocale uLocale)
Construct a flexible generator according to data for a given locale.
| Parameters | |
|---|---|
uLocale |
ULocale: The locale to pass. |
| Returns | |
|---|---|
DateTimePatternGenerator |
|
getSkeleton
public String getSkeleton (String pattern)
Utility to return a unique skeleton from a given pattern. For example, both "MMM-dd" and "dd/MMM" produce the skeleton "MMMdd".
| Parameters | |
|---|---|
pattern |
String: Input pattern, such as "dd/MMM" |
| Returns | |
|---|---|
String |
skeleton, such as "MMMdd" |
getSkeletons
public Map<String, String> getSkeletons (Map<String, String> result)
Return a list of all the skeletons (in canonical form) from this class, and the patterns that they map to.
| Parameters | |
|---|---|
result |
Map: an output Map in which to place the mapping from skeleton to
pattern. If you want to see the internal order being used,
supply a LinkedHashMap. If the input value is null, then a
LinkedHashMap is allocated.
Issue: an alternate API would be to just return a list of the skeletons, and then have a separate routine to get from skeleton to pattern. |
| Returns | |
|---|---|
Map<String, String> |
the input Map containing the values. |
isFrozen
public boolean isFrozen ()
Determines whether the object has been frozen or not.
| Returns | |
|---|---|
boolean |
|
replaceFieldTypes
public String replaceFieldTypes (String pattern, String skeleton)
Adjusts the field types (width and subtype) of a pattern to match what is in a skeleton. That is, if you supply a pattern like "d-M H:m", and a skeleton of "MMMMddhhmm", then the input pattern is adjusted to be "dd-MMMM hh:mm". This is used internally to get the best match for the input skeleton, but can also be used externally.
Example code:
Date date= new GregorianCalendar(1999,9,13,23,58,59).getTime();
TimeZone zone = TimeZone.getTimeZone("Europe/Paris");
ULocale locale = ULocale.FRANCE;
DateTimePatternGenerator gen = DateTimePatternGenerator.getInstance(locale);
SimpleDateFormat format = new SimpleDateFormat("EEEE d MMMM y HH:mm:ss zzzz",locale);
format.setTimeZone(zone);
String pattern = format.toPattern();
System.out.println("Pattern before replacement:");
System.out.println(pattern);
System.out.println("Date/Time format in fr_FR:");
System.out.println(format.format(date));
// Replace zone "zzzz" in the pattern with "vvvv"
String newPattern = gen.replaceFieldTypes(pattern, "vvvv");
// Apply the new pattern
format.applyPattern(newPattern);
System.out.println("Pattern after replacement:");
System.out.println(newPattern);
System.out.println("Date/Time format in fr_FR:");
System.out.println(format.format(date));
/** output of the sample code:
***************************************************************************************************
Pattern before replacement:
EEEE d MMMM y HH:mm:ss zzzz
Date/Time format in fr_FR:
jeudi 14 octobre 1999 05:58:59 heure avancée d’Europe centrale
Pattern after replacement:
EEEE d MMMM y HH:mm:ss vvvv
Date/Time format in fr_FR:
jeudi 14 octobre 1999 05:58:59 heure de l’Europe centrale
**************************************************************************************************/| Parameters | |
|---|---|
pattern |
String: input pattern |
skeleton |
String: For the pattern to match to. |
| Returns | |
|---|---|
String |
pattern adjusted to match the skeleton fields widths and subtypes. |
replaceFieldTypes
public String replaceFieldTypes (String pattern, String skeleton, int options)
Adjusts the field types (width and subtype) of a pattern to match what is in a skeleton. That is, if you supply a pattern like "d-M H:m", and a skeleton of "MMMMddhhmm", then the input pattern is adjusted to be "dd-MMMM hh:mm". This is used internally to get the best match for the input skeleton, but can also be used externally.
| Parameters | |
|---|---|
pattern |
String: input pattern |
skeleton |
String: For the pattern to match to. |
options |
int: MATCH_xxx options for forcing the length of specified fields in
the returned pattern to match those in the skeleton (when this would
not happen otherwise). For default behavior, use MATCH_NO_OPTIONS. |
| Returns | |
|---|---|
String |
pattern adjusted to match the skeleton fields widths and subtypes. |
setAppendItemFormat
public void setAppendItemFormat (int field,
String value)An AppendItem format is a pattern used to append a field if there is no good match. For example, suppose that the input skeleton is "GyyyyMMMd", and there is no matching pattern internally, but there is a pattern matching "yyyyMMMd", say "d-MM-yyyy". Then that pattern is used, plus the G. The way these two are conjoined is by using the AppendItemFormat for G (era). So if that value is, say "{0}, {1}" then the final resulting pattern is "d-MM-yyyy, G".
There are actually three available variables: {0} is the pattern so far, {1} is the element we are adding, and {2} is the name of the element.
This reflects the way that the CLDR data is organized.
| Parameters | |
|---|---|
field |
int: such as ERA |
value |
String: pattern, such as "{0}, {1}" |
setAppendItemName
public void setAppendItemName (int field,
String value)Sets the names of fields, eg "era" in English for ERA. These are only used if the corresponding AppendItemFormat is used, and if it contains a {2} variable.
This reflects the way that the CLDR data is organized.
| Parameters | |
|---|---|
field |
int: Index of the append item names. |
value |
String: The value to set the item to. |
setDateTimeFormat
public void setDateTimeFormat (String dateTimeFormat)
The date time format is a message format pattern used to compose date and time patterns. The default value is "{1} {0}", where {1} will be replaced by the date pattern and {0} will be replaced by the time pattern.
This is used when the input skeleton contains both date and time fields, but there is not a close match among the added patterns. For example, suppose that this object was created by adding "dd-MMM" and "hh:mm", and its datetimeFormat is the default "{1} {0}". Then if the input skeleton is "MMMdhmm", there is not an exact match, so the input skeleton is broken up into two components "MMMd" and "hmm". There are close matches for those two skeletons, so the result is put together with this pattern, resulting in "d-MMM h:mm". There are four DateTimeFormats in a DateTimePatternGenerator object, corresponding to date styles DateFormat.FULL..DateFormat.SHORT. This method sets all of them to the specified pattern. To set them individually, see setDateTimeFormat(int style, ...).
| Parameters | |
|---|---|
dateTimeFormat |
String: message format pattern, where {1} will be replaced by the date
pattern and {0} will be replaced by the time pattern. |
setDateTimeFormat
public void setDateTimeFormat (int style,
String dateTimeFormat)dateTimeFormats are message patterns used to compose combinations of date and time patterns. There are four length styles, corresponding to the inferred style of the date pattern: - DateFormat.FULL (for date pattern with weekday and long month), else - DateFormat.LONG (for a date pattern with long month), else - DateFormat.MEDIUM (for a date pattern with abbreviated month), else - DateFormat.SHORT (for any other date pattern). For details on dateTimeFormats, see https://www.unicode.org/reports/tr35/tr35-dates.html#dateTimeFormats. The default pattern in the root locale for all styles is "{1} {0}".
| Parameters | |
|---|---|
style |
int: one of DateFormat.FULL..DateFormat.SHORT. An exception will
be thrown if out of range. |
dateTimeFormat |
String: the new dateTimeFormat to set for the specified style |
setDecimal
public void setDecimal (String decimal)
The decimal value is used in formatting fractions of seconds. If the skeleton contains fractional seconds, then this is used with the fractional seconds. For example, suppose that the input pattern is "hhmmssSSSS", and the best matching pattern internally is "H:mm:ss", and the decimal string is ",". Then the resulting pattern is modified to be "H:mm:ss,SSSS"
| Parameters | |
|---|---|
decimal |
String: The decimal to set to. |
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Last updated 2024-12-18 UTC.