International Components for Unicode for Java (icu4j) 74.2 · com.ibm.icu.text.PluralFormat

PluralFormat supports the creation of internationalized messages with plural inflection. It is based on plural selection, i.e. the caller specifies messages for each plural case that can appear in the user's language and the PluralFormat selects the appropriate message based on the number.

The Problem of Plural Forms in Internationalized Messages

Different languages have different ways to inflect plurals. Creating internationalized messages that include plural forms is only feasible when the framework is able to handle plural forms of all languages correctly. ChoiceFormat doesn't handle this well, because it attaches a number interval to each message and selects the message whose interval contains a given number. This can only handle a finite number of intervals. But in some languages, like Polish, one plural case applies to infinitely many intervals (e.g., the paucal case applies to numbers ending with 2, 3, or 4 except those ending with 12, 13, or 14). Thus ChoiceFormat is not adequate.

PluralFormat deals with this by breaking the problem into two parts:

It uses PluralRules that can define more complex conditions for a plural case than just a single interval. These plural rules define both what plural cases exist in a language, and to which numbers these cases apply.
It provides predefined plural rules for many languages. Thus, the programmer need not worry about the plural cases of a language and does not have to define the plural cases; they can simply use the predefined keywords. The whole plural formatting of messages can be done using localized patterns from resource bundles. For predefined plural rules, see the CLDR Language Plural Rules page at https://unicode-org.github.io/cldr-staging/charts/latest/supplemental/language_plural_rules.html

Usage of `PluralFormat`

Note

Typically, plural formatting is done via MessageFormat with a plural argument type, rather than using a stand-alone PluralFormat.

This discussion assumes that you use PluralFormat with a predefined set of plural rules. You can create one using one of the constructors that takes a ULocale object. To specify the message pattern, you can either pass it to the constructor or set it explicitly using the applyPattern() method. The format() method takes a number object and selects the message of the matching plural case. This message will be returned.

Patterns and Their Interpretation

The pattern text defines the message output for each plural case of the specified locale. Syntax:

pluralStyle = [offsetValue] (selector '{' message '}')+
offsetValue = "offset:" number
selector = explicitValue | keyword
explicitValue = '=' number  // adjacent, no white space in between
keyword = [^[[:Pattern_Syntax:][:Pattern_White_Space:]]]+
message: see MessageFormat

Pattern_White_Space between syntax elements is ignored, except between the {curly braces} and their sub-message, and between the '=' and the number of an explicitValue.

There are 6 predefined case keywords in CLDR/ICU - 'zero', 'one', 'two', 'few', 'many' and 'other'. You always have to define a message text for the default plural case "other" which is contained in every rule set. If you do not specify a message text for a particular plural case, the message text of the plural case "other" gets assigned to this plural case.

When formatting, the input number is first matched against the explicitValue clauses. If there is no exact-number match, then a keyword is selected by calling the PluralRules with the input number minus the offset. (The offset defaults to 0 if it is omitted from the pattern string.) If there is no clause with that keyword, then the "other" clauses is returned.

An unquoted pound sign (#) in the selected sub-message itself (i.e., outside of arguments nested in the sub-message) is replaced by the input number minus the offset. The number-minus-offset value is formatted using a NumberFormat for the PluralFormat's locale. If you need special number formatting, you have to use a MessageFormat and explicitly specify a NumberFormat argument

Note

That argument is formatting without subtracting the offset! If you need a custom format and have a non-zero offset, then you need to pass the number-minus-offset value as a separate parameter.

For a usage example, see the MessageFormat class documentation.

Defining Custom Plural Rules

If you need to use PluralFormat with custom rules, you can create a PluralRules object and pass it to PluralFormat's constructor. If you also specify a locale in this constructor, this locale will be used to format the number in the message texts.

For more information about PluralRules, see PluralRules.

Nested and Inner Type Summary

Modifier and Type	Class and Description
pack-priv static interface	PluralFormat.PluralSelector Interface for selecting PluralFormat keywords for numbers.
private class	PluralFormat.PluralSelectorAdapter

Field Summary

Modifier and Type	Field and Description
private transient MessagePattern	msgPattern The MessagePattern which contains the parsed structure of the pattern string.
private NumberFormat	numberFormat This `NumberFormat` is used for the standard formatting of the number inserted into the message.
private transient double	offset The offset to subtract before invoking plural rules.
private Map<String, String>	parsedValues Obsolete with use of MessagePattern since ICU 4.8.
private String	pattern The applied pattern string.
private PluralRules	pluralRules The plural rules used for plural selection.
private transient PluralFormat.PluralSelectorAdapter	pluralRulesWrapper
private static final long	serialVersionUID Hides com.ibm.icu.text.UFormat.serialVersionUID.
private ULocale	ulocale The locale used for standard number formatting and getting the predefined plural rules (if they were not defined explicitely).

Constructor Summary

Access	Constructor and Description
public	PluralFormat() Creates a new cardinal-number `PluralFormat` for the default `FORMAT` locale.
public	PluralFormat(ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. ulocale) Creates a new cardinal-number `PluralFormat` for a given locale.
public	PluralFormat(Locale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. locale) Creates a new cardinal-number `PluralFormat` for a given `java.util.Locale`.
public	PluralFormat(PluralRules defines the behavior of the `PluralFormat` object. rules) Creates a new cardinal-number `PluralFormat` for a given set of rules.
public	PluralFormat(ULocale the default number formatting will be done using this locale. ulocale, PluralRules defines the behavior of the `PluralFormat` object. rules) Creates a new cardinal-number `PluralFormat` for a given set of rules.
public	PluralFormat(Locale the default number formatting will be done using this locale. locale, PluralRules defines the behavior of the `PluralFormat` object. rules) Creates a new cardinal-number `PluralFormat` for a given set of rules.
public	PluralFormat(ULocale the default number formatting will be done using this locale. ulocale, PluralRules.PluralType The plural type (e.g., cardinal or ordinal). type) Creates a new `PluralFormat` for the plural type.
public	PluralFormat(Locale the default number formatting will be done using this locale. locale, PluralRules.PluralType The plural type (e.g., cardinal or ordinal). type) Creates a new `PluralFormat` for the plural type.
public	PluralFormat(String the pattern for this `PluralFormat`. pattern) Creates a new cardinal-number `PluralFormat` for a given pattern string.
public	PluralFormat(ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. ulocale, String the pattern for this `PluralFormat`. pattern) Creates a new cardinal-number `PluralFormat` for a given pattern string and locale.
public	PluralFormat(PluralRules defines the behavior of the `PluralFormat` object. rules, String the pattern for this `PluralFormat`. pattern) Creates a new cardinal-number `PluralFormat` for a given set of rules and a pattern.
public	PluralFormat(ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. ulocale, PluralRules defines the behavior of the `PluralFormat` object. rules, String the pattern for this `PluralFormat`. pattern) Creates a new cardinal-number `PluralFormat` for a given set of rules, a pattern and a locale.
public	PluralFormat(ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. ulocale, PluralRules.PluralType The plural type (e.g., cardinal or ordinal). type, String the pattern for this `PluralFormat`. pattern) Creates a new `PluralFormat` for a plural type, a pattern and a locale.
pack-priv	PluralFormat(ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. ulocale, PluralRules.PluralType The plural type (e.g., cardinal or ordinal). type, String the pattern for this `PluralFormat`. pattern, NumberFormat The number formatter to use. numberFormat) Creates a new `PluralFormat` for a plural type, a pattern and a locale.

Method Summary

Modifier and Type	Method and Description
public void	applyPattern(String the pattern for this plural format. pattern) Sets the pattern used by this plural format.
public boolean	equals(Object the reference object with which to compare. rhs) Overrides java.lang.Object.equals. Indicates whether some other object is "equal to" this one.
public boolean	Returns: true if this equals rhs equals(PluralFormat the PluralFormat to compare against rhs) Returns true if this equals the provided PluralFormat.
pack-priv static int	Returns: the sub-message start part index. findSubMessage(MessagePattern A MessagePattern. pattern, int the index of the first PluralFormat argument style part. partIndex, PluralFormat.PluralSelector the PluralSelector for mapping the number (minus offset) to a keyword. selector, Object worker object for the selector. context, double a number to be matched to one of the PluralFormat argument's explicit values, or mapped via the PluralSelector. number) Finds the PluralFormat sub-message for the given number, or the "other" sub-message.
public final String	Returns: the string containing the formatted plural message. format(double a number for which the plural message should be formatted. If no pattern has been applied to this `PluralFormat` object yet, the formatted number will be returned. number) Formats a plural message for a given number.
public StringBuffer	Returns: the string buffer passed in as toAppendTo, with formatted text appended. format(Object a number object (instance of `Number` for which the plural message should be formatted. If no pattern has been applied to this `PluralFormat` object yet, the formatted number will be returned. Note If this object is not an instance of `Number`, the `toAppendTo` will not be modified. number, StringBuffer the formatted message will be appended to this `StringBuffer`. toAppendTo, FieldPosition will be ignored by this method. pos) Implements abstract java.text.Format.format. Formats a plural message for a given number and appends the formatted message to the given `StringBuffer`.
private String	format(Number numberObject, double number)
public int	hashCode() Overrides java.lang.Object.hashCode. Returns a hash code value for the object.
private void	init(PluralRules rules, PluralRules.PluralType type, ULocale locale, NumberFormat numberFormat)
public Number	Returns: nothing because this method is not yet implemented. parse(String the string to be parsed. text, ParsePosition defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position has not changed upon return, then parsing failed. parsePosition) This method is not yet supported by `PluralFormat`.
public Object	Returns: nothing because this method is not yet implemented. parseObject(String the string to be parsed. source, ParsePosition defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position has not changed upon return, then parsing failed. pos) Implements abstract java.text.Format.parseObject. This method is not yet supported by `PluralFormat`.
pack-priv String	Returns: Returns the PluralRules type. For example, it could be "zero", "one", "two", "few", "many" or "other") parseType(String the string to be parsed. source, RbnfLenientScanner scanner, FieldPosition defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position is a negative index, then parsing failed. pos) Deprecated as a consequence of `RbnfLenientScanner` being deprecated. This method returns the PluralRules type found from parsing.
private void	readObject(ObjectInputStream in)
private void	resetPattern()
public void	setLocale(ULocale the `ULocale` used to configure the formatter. If `ulocale` is `null`, the default `FORMAT` locale will be used. ulocale) Deprecated ICU 50 This method clears the pattern and might create a different kind of PluralRules instance; use one of the constructors to create a new instance instead. Sets the locale used by this `PluraFormat` object.
public void	setNumberFormat(NumberFormat the number format to use. format) Sets the number format used by this formatter.
public String	Returns: the pattern string toPattern() Returns the pattern for this PluralFormat.
public String	toString() Overrides java.lang.Object.toString. Returns a string representation of the object.

Inherited from com.ibm.icu.text.UFormat:: getLocale setLocale

Field Detail

msgPattern	back to summary
private transient MessagePattern msgPattern The MessagePattern which contains the parsed structure of the pattern string.

numberFormat	back to summary
private NumberFormat numberFormat This `NumberFormat` is used for the standard formatting of the number inserted into the message.

offset	back to summary
private transient double offset The offset to subtract before invoking plural rules.

parsedValues	back to summary
private Map<String, String> parsedValues Obsolete with use of MessagePattern since ICU 4.8. Used to be: The format messages for each plural case. It is a mapping: `String`(plural case keyword) --> `String` (message for this plural case).

pattern	back to summary
private String pattern The applied pattern string.

pluralRules	back to summary
private PluralRules pluralRules The plural rules used for plural selection.

pluralRulesWrapper	back to summary
private transient PluralFormat.PluralSelectorAdapter pluralRulesWrapper

serialVersionUID	back to summary
private static final long serialVersionUID Hides com.ibm.icu.text.UFormat.serialVersionUID.

ulocale	back to summary
private ULocale ulocale The locale used for standard number formatting and getting the predefined plural rules (if they were not defined explicitely).

Constructor Detail

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat() Creates a new cardinal-number `PluralFormat` for the default `FORMAT` locale. This locale will be used to get the set of plural rules and for standard number formatting. ICU Status Stable since ICU 3.8. See Also `Category#FORMAT`

public PluralFormat()

Creates a new cardinal-number PluralFormat for the default FORMAT locale. This locale will be used to get the set of plural rules and for standard number formatting.

ICU Status: Stable since ICU 3.8.
See Also: Category#FORMAT

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(ULocale ulocale) Creates a new cardinal-number `PluralFormat` for a given locale. Parameters ulocale:ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. ICU Status Stable since ICU 3.8.

public PluralFormat(ULocale ulocale)

Creates a new cardinal-number PluralFormat for a given locale.

Parameters

ulocale:ULocale: the PluralFormat will be configured with rules for this locale. This locale will also be used for standard number formatting.

ICU Status

Stable since ICU 3.8.

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(Locale locale) Creates a new cardinal-number `PluralFormat` for a given `java.util.Locale`. Parameters locale:Locale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. ICU Status Stable since ICU 54.

public PluralFormat(Locale locale)

Creates a new cardinal-number PluralFormat for a given java.util.Locale.

Parameters

locale:Locale: the PluralFormat will be configured with rules for this locale. This locale will also be used for standard number formatting.

ICU Status

Stable since ICU 54.

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(PluralRules rules) Creates a new cardinal-number `PluralFormat` for a given set of rules. The standard number formatting will be done using the default `FORMAT` locale. Parameters rules:PluralRules defines the behavior of the `PluralFormat` object. ICU Status Stable since ICU 3.8. See Also `Category#FORMAT`

public PluralFormat(PluralRules rules)

Creates a new cardinal-number PluralFormat for a given set of rules. The standard number formatting will be done using the default FORMAT locale.

Parameters

rules:PluralRules: defines the behavior of the PluralFormat object.

ICU Status

Stable since ICU 3.8.

See Also

Category#FORMAT

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(ULocale ulocale, PluralRules rules) Creates a new cardinal-number `PluralFormat` for a given set of rules. The standard number formatting will be done using the given locale. Parameters ulocale:ULocale the default number formatting will be done using this locale. rules:PluralRules defines the behavior of the `PluralFormat` object. ICU Status Stable since ICU 3.8.

public PluralFormat(ULocale ulocale, PluralRules rules)

Creates a new cardinal-number PluralFormat for a given set of rules. The standard number formatting will be done using the given locale.

Parameters

ulocale:ULocale: the default number formatting will be done using this locale.
rules:PluralRules: defines the behavior of the PluralFormat object.

ICU Status

Stable since ICU 3.8.

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(Locale locale, PluralRules rules) Creates a new cardinal-number `PluralFormat` for a given set of rules. The standard number formatting will be done using the given locale. Parameters locale:Locale the default number formatting will be done using this locale. rules:PluralRules defines the behavior of the `PluralFormat` object. ICU Status Stable since ICU 54.

public PluralFormat(Locale locale, PluralRules rules)

Creates a new cardinal-number PluralFormat for a given set of rules. The standard number formatting will be done using the given locale.

Parameters

locale:Locale: the default number formatting will be done using this locale.
rules:PluralRules: defines the behavior of the PluralFormat object.

ICU Status

Stable since ICU 54.

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(ULocale ulocale, PluralRules.PluralType type) Creates a new `PluralFormat` for the plural type. The standard number formatting will be done using the given locale. Parameters ulocale:ULocale the default number formatting will be done using this locale. type:PluralRules.PluralType The plural type (e.g., cardinal or ordinal). ICU Status Stable since ICU 50.

public PluralFormat(ULocale ulocale, PluralRules.PluralType type)

Creates a new PluralFormat for the plural type. The standard number formatting will be done using the given locale.

Parameters

ulocale:ULocale: the default number formatting will be done using this locale.
type:PluralRules.PluralType: The plural type (e.g., cardinal or ordinal).

ICU Status

Stable since ICU 50.

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(Locale locale, PluralRules.PluralType type) Creates a new `PluralFormat` for the plural type. The standard number formatting will be done using the given `java.util.Locale`. Parameters locale:Locale the default number formatting will be done using this locale. type:PluralRules.PluralType The plural type (e.g., cardinal or ordinal). ICU Status Stable since ICU 54.

public PluralFormat(Locale locale, PluralRules.PluralType type)

Creates a new PluralFormat for the plural type. The standard number formatting will be done using the given java.util.Locale.

Parameters

locale:Locale: the default number formatting will be done using this locale.
type:PluralRules.PluralType: The plural type (e.g., cardinal or ordinal).

ICU Status

Stable since ICU 54.

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(String pattern) Creates a new cardinal-number `PluralFormat` for a given pattern string. The default `FORMAT` locale will be used to get the set of plural rules and for standard number formatting. Parameters pattern:String the pattern for this `PluralFormat`. Exceptions IllegalArgumentException: if the pattern is invalid. ICU Status Stable since ICU 3.8. See Also `Category#FORMAT`

public PluralFormat(String pattern)

Creates a new cardinal-number PluralFormat for a given pattern string. The default FORMAT locale will be used to get the set of plural rules and for standard number formatting.

Parameters

pattern:String: the pattern for this PluralFormat.

Exceptions

IllegalArgumentException:: if the pattern is invalid.

ICU Status

Stable since ICU 3.8.

See Also

Category#FORMAT

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(ULocale ulocale, String pattern) Creates a new cardinal-number `PluralFormat` for a given pattern string and locale. The locale will be used to get the set of plural rules and for standard number formatting. Example code:{@. jcite com.ibm.icu.samples.text.pluralformat.PluralFormatSample:---PluralFormatExample} Parameters ulocale:ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. pattern:String the pattern for this `PluralFormat`. Exceptions IllegalArgumentException: if the pattern is invalid. ICU Status Stable since ICU 3.8.

public PluralFormat(ULocale ulocale, String pattern)

Creates a new cardinal-number PluralFormat for a given pattern string and locale. The locale will be used to get the set of plural rules and for standard number formatting.

Example code:{@. jcite com.ibm.icu.samples.text.pluralformat.PluralFormatSample:---PluralFormatExample}

Parameters

ulocale:ULocale: the PluralFormat will be configured with rules for this locale. This locale will also be used for standard number formatting.
pattern:String: the pattern for this PluralFormat.

Exceptions

IllegalArgumentException:: if the pattern is invalid.

ICU Status

Stable since ICU 3.8.

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(PluralRules rules, String pattern) Creates a new cardinal-number `PluralFormat` for a given set of rules and a pattern. The standard number formatting will be done using the default `FORMAT` locale. Parameters rules:PluralRules defines the behavior of the `PluralFormat` object. pattern:String the pattern for this `PluralFormat`. Exceptions IllegalArgumentException: if the pattern is invalid. ICU Status Stable since ICU 3.8. See Also `Category#FORMAT`

public PluralFormat(PluralRules rules, String pattern)

Creates a new cardinal-number PluralFormat for a given set of rules and a pattern. The standard number formatting will be done using the default FORMAT locale.

Parameters

rules:PluralRules: defines the behavior of the PluralFormat object.
pattern:String: the pattern for this PluralFormat.

Exceptions

IllegalArgumentException:: if the pattern is invalid.

ICU Status

Stable since ICU 3.8.

See Also

Category#FORMAT

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(ULocale ulocale, PluralRules rules, String pattern) Creates a new cardinal-number `PluralFormat` for a given set of rules, a pattern and a locale. Parameters ulocale:ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. rules:PluralRules defines the behavior of the `PluralFormat` object. pattern:String the pattern for this `PluralFormat`. Exceptions IllegalArgumentException: if the pattern is invalid. ICU Status Stable since ICU 3.8.

public PluralFormat(ULocale ulocale, PluralRules rules, String pattern)

Creates a new cardinal-number PluralFormat for a given set of rules, a pattern and a locale.

Parameters

ulocale:ULocale: the PluralFormat will be configured with rules for this locale. This locale will also be used for standard number formatting.
rules:PluralRules: defines the behavior of the PluralFormat object.
pattern:String: the pattern for this PluralFormat.

Exceptions

IllegalArgumentException:: if the pattern is invalid.

ICU Status

Stable since ICU 3.8.

PluralFormat back to summary

PluralFormat	back to summary
public PluralFormat(ULocale ulocale, PluralRules.PluralType type, String pattern) Creates a new `PluralFormat` for a plural type, a pattern and a locale. Parameters ulocale:ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. type:PluralRules.PluralType The plural type (e.g., cardinal or ordinal). pattern:String the pattern for this `PluralFormat`. Exceptions IllegalArgumentException: if the pattern is invalid. ICU Status Stable since ICU 50.

public PluralFormat(ULocale ulocale, PluralRules.PluralType type, String pattern)

Creates a new PluralFormat for a plural type, a pattern and a locale.

Parameters

ulocale:ULocale: the PluralFormat will be configured with rules for this locale. This locale will also be used for standard number formatting.
type:PluralRules.PluralType: The plural type (e.g., cardinal or ordinal).
pattern:String: the pattern for this PluralFormat.

Exceptions

IllegalArgumentException:: if the pattern is invalid.

ICU Status

Stable since ICU 50.

PluralFormat back to summary

PluralFormat	back to summary
pack-priv PluralFormat(ULocale ulocale, PluralRules.PluralType type, String pattern, NumberFormat numberFormat) Creates a new `PluralFormat` for a plural type, a pattern and a locale. Parameters ulocale:ULocale the `PluralFormat` will be configured with rules for this locale. This locale will also be used for standard number formatting. type:PluralRules.PluralType The plural type (e.g., cardinal or ordinal). pattern:String the pattern for this `PluralFormat`. numberFormat:NumberFormat The number formatter to use. Exceptions IllegalArgumentException: if the pattern is invalid.

pack-priv PluralFormat(ULocale ulocale, PluralRules.PluralType type, String pattern, NumberFormat numberFormat)

Creates a new PluralFormat for a plural type, a pattern and a locale.

Parameters

ulocale:ULocale: the PluralFormat will be configured with rules for this locale. This locale will also be used for standard number formatting.
type:PluralRules.PluralType: The plural type (e.g., cardinal or ordinal).
pattern:String: the pattern for this PluralFormat.
numberFormat:NumberFormat: The number formatter to use.

Exceptions

IllegalArgumentException:: if the pattern is invalid.

Method Detail

applyPattern	back to summary
public void applyPattern(String pattern) Sets the pattern used by this plural format. The method parses the pattern and creates a map of format strings for the plural rules. Patterns and their interpretation are specified in the class description. Parameters pattern:String the pattern for this plural format. Exceptions IllegalArgumentException: if the pattern is invalid. ICU Status Stable since ICU 3.8.

applyPattern

back to summary

public void applyPattern(String pattern)

Sets the pattern used by this plural format. The method parses the pattern and creates a map of format strings for the plural rules. Patterns and their interpretation are specified in the class description.

Parameters

pattern:String: the pattern for this plural format.

Exceptions

IllegalArgumentException:: if the pattern is invalid.

ICU Status

Stable since ICU 3.8.

equals back to summary

equals	back to summary
public boolean equals(Object rhs) Overrides java.lang.Object.equals. Doc from java.lang.Object.equals. Indicates whether some other object is "equal to" this one. The `equals` method implements an equivalence relation on non-null object references: It is reflexive: for any non-null reference value `x`, `x.equals(x)` should return `true`. It is symmetric: for any non-null reference values `x` and `y`, `x.equals(y)` should return `true` if and only if `y.equals(x)` returns `true`. It is transitive: for any non-null reference values `x`, `y`, and `z`, if `x.equals(y)` returns `true` and `y.equals(z)` returns `true`, then `x.equals(z)` should return `true`. It is consistent: for any non-null reference values `x` and `y`, multiple invocations of `x.equals(y)` consistently return `true` or consistently return `false`, provided no information used in `equals` comparisons on the objects is modified. For any non-null reference value `x`, `x.equals(null)` should return `false`. An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes. Parameters rhs:Object the reference object with which to compare. Returns:boolean `true` if this object is the same as the obj argument; `false` otherwise. Annotations @Override ICU Status Stable since ICU 3.8.

public boolean equals(Object rhs)

Overrides java.lang.Object.equals.

Doc from java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

It is reflexive: for any non-null reference value x, x.equals(x) should return true.
It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters

rhs:Object: the reference object with which to compare.

Returns:boolean

true if this object is the same as the obj argument; false otherwise.

Annotations

@Override

ICU Status

Stable since ICU 3.8.

equals	back to summary
public boolean equals(PluralFormat rhs) Returns true if this equals the provided PluralFormat. Parameters rhs:PluralFormat the PluralFormat to compare against Returns:boolean true if this equals rhs ICU Status Stable since ICU 3.8.

equals

back to summary

public boolean equals(PluralFormat rhs)

Returns true if this equals the provided PluralFormat.

Parameters

rhs:PluralFormat: the PluralFormat to compare against

Returns:boolean

true if this equals rhs

ICU Status

Stable since ICU 3.8.

findSubMessage	back to summary
pack-priv static int findSubMessage(MessagePattern pattern, int partIndex, PluralFormat.PluralSelector selector, Object context, double number) Finds the PluralFormat sub-message for the given number, or the "other" sub-message. Parameters pattern:MessagePattern A MessagePattern. partIndex:int the index of the first PluralFormat argument style part. selector:PluralFormat.PluralSelector the PluralSelector for mapping the number (minus offset) to a keyword. context:Object worker object for the selector. number:double a number to be matched to one of the PluralFormat argument's explicit values, or mapped via the PluralSelector. Returns:int the sub-message start part index.

findSubMessage

back to summary

pack-priv static int findSubMessage(MessagePattern pattern, int partIndex, PluralFormat.PluralSelector selector, Object context, double number)

Finds the PluralFormat sub-message for the given number, or the "other" sub-message.

Parameters

pattern:MessagePattern: A MessagePattern.
partIndex:int: the index of the first PluralFormat argument style part.
selector:PluralFormat.PluralSelector: the PluralSelector for mapping the number (minus offset) to a keyword.
context:Object: worker object for the selector.
number:double: a number to be matched to one of the PluralFormat argument's explicit values, or mapped via the PluralSelector.

Returns:int

the sub-message start part index.

format back to summary

format	back to summary
public final String format(double number) Formats a plural message for a given number. Parameters number:double a number for which the plural message should be formatted. If no pattern has been applied to this `PluralFormat` object yet, the formatted number will be returned. Returns:String the string containing the formatted plural message. ICU Status Stable since ICU 4.0.

public final String format(double number)

Formats a plural message for a given number.

Parameters

number:double: a number for which the plural message should be formatted. If no pattern has been applied to this PluralFormat object yet, the formatted number will be returned.

Returns:String

the string containing the formatted plural message.

ICU Status

Stable since ICU 4.0.

format back to summary

format	back to summary
public StringBuffer format(Object number, StringBuffer toAppendTo, FieldPosition pos) Implements abstract java.text.Format.format. Formats a plural message for a given number and appends the formatted message to the given `StringBuffer`. Parameters number:Object a number object (instance of `Number` for which the plural message should be formatted. If no pattern has been applied to this `PluralFormat` object yet, the formatted number will be returned. Note If this object is not an instance of `Number`, the `toAppendTo` will not be modified. toAppendTo:StringBuffer the formatted message will be appended to this `StringBuffer`. pos:FieldPosition will be ignored by this method. Returns:StringBuffer the string buffer passed in as toAppendTo, with formatted text appended. Annotations @Override Exceptions IllegalArgumentException: if number is not an instance of Number ICU Status Stable since ICU 3.8.

public StringBuffer format(Object number, StringBuffer toAppendTo, FieldPosition pos)

Implements abstract java.text.Format.format.

Formats a plural message for a given number and appends the formatted message to the given StringBuffer.

Parameters

number:Object: a number object (instance of Number for which the plural message should be formatted. If no pattern has been applied to this PluralFormat object yet, the formatted number will be returned.
Note
If this object is not an instance of Number, the toAppendTo will not be modified.
toAppendTo:StringBuffer: the formatted message will be appended to this StringBuffer.
pos:FieldPosition: will be ignored by this method.

Returns:StringBuffer

the string buffer passed in as toAppendTo, with formatted text appended.

Annotations

@Override

Exceptions

IllegalArgumentException:: if number is not an instance of Number

ICU Status

Stable since ICU 3.8.

format	back to summary
private String format(Number numberObject, double number)

hashCode back to summary

hashCode	back to summary
public int hashCode() Overrides java.lang.Object.hashCode. Doc from java.lang.Object.hashCode. Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by `java.util.HashMap`. The general contract of `hashCode` is: Whenever it is invoked on the same object more than once during an execution of a Java application, the `hashCode` method must consistently return the same integer, provided no information used in `equals` comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. If two objects are equal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce the same integer result. It is not required that if two objects are unequal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables. Returns:int a hash code value for this object. Annotations @Override ICU Status Stable since ICU 3.8.

public int hashCode()

Overrides java.lang.Object.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

Returns:int

a hash code value for this object.

Annotations

@Override

ICU Status

Stable since ICU 3.8.

init	back to summary
private void init(PluralRules rules, PluralRules.PluralType type, ULocale locale, NumberFormat numberFormat)

parse back to summary

parse	back to summary
public Number parse(String text, ParsePosition parsePosition) This method is not yet supported by `PluralFormat`. Parameters text:String the string to be parsed. parsePosition:ParsePosition defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position has not changed upon return, then parsing failed. Returns:Number nothing because this method is not yet implemented. Exceptions UnsupportedOperationException: will always be thrown by this method. ICU Status Stable since ICU 3.8.

public Number parse(String text, ParsePosition parsePosition)

This method is not yet supported by PluralFormat.

Parameters

text:String: the string to be parsed.
parsePosition:ParsePosition: defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position has not changed upon return, then parsing failed.

Returns:Number

nothing because this method is not yet implemented.

Exceptions

UnsupportedOperationException:: will always be thrown by this method.

ICU Status

Stable since ICU 3.8.

parseObject back to summary

parseObject	back to summary
public Object parseObject(String source, ParsePosition pos) Implements abstract java.text.Format.parseObject. This method is not yet supported by `PluralFormat`. Parameters source:String the string to be parsed. pos:ParsePosition defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position has not changed upon return, then parsing failed. Returns:Object nothing because this method is not yet implemented. Annotations @Override Exceptions UnsupportedOperationException: will always be thrown by this method. ICU Status Stable since ICU 3.8.

public Object parseObject(String source, ParsePosition pos)

Implements abstract java.text.Format.parseObject.

This method is not yet supported by PluralFormat.

Parameters

source:String: the string to be parsed.
pos:ParsePosition: defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position has not changed upon return, then parsing failed.

Returns:Object

nothing because this method is not yet implemented.

Annotations

@Override

Exceptions

UnsupportedOperationException:: will always be thrown by this method.

ICU Status

Stable since ICU 3.8.

parseType back to summary

parseType	back to summary
pack-priv String parseType(String source, RbnfLenientScanner scanner, FieldPosition pos) Deprecated as a consequence of `RbnfLenientScanner` being deprecated. See corresponding docs for further information. This method returns the PluralRules type found from parsing. Parameters source:String the string to be parsed. pos:FieldPosition defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position is a negative index, then parsing failed. Returns:String Returns the PluralRules type. For example, it could be "zero", "one", "two", "few", "many" or "other")

pack-priv String parseType(String source, RbnfLenientScanner scanner, FieldPosition pos)

Deprecated

as a consequence of RbnfLenientScanner being deprecated. See corresponding docs for further information.

This method returns the PluralRules type found from parsing.

Parameters

source:String: the string to be parsed.
pos:FieldPosition: defines the position where parsing is to begin, and upon return, the position where parsing left off. If the position is a negative index, then parsing failed.

Returns:String

Returns the PluralRules type. For example, it could be "zero", "one", "two", "few", "many" or "other")

readObject	back to summary
private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException

resetPattern	back to summary
private void resetPattern()

setLocale back to summary

setLocale	back to summary
public void setLocale(ULocale ulocale) Deprecated ICU 50 This method clears the pattern and might create a different kind of PluralRules instance; use one of the constructors to create a new instance instead. Sets the locale used by this `PluraFormat` object. Note Calling this method resets this `PluraFormat` object, i.e., a pattern that was applied previously will be removed, and the NumberFormat is set to the default number format for the locale. The resulting format behaves the same as one constructed from `PluralFormat(ULocale, PluralRules.PluralType)` with PluralType.CARDINAL. Parameters ulocale:ULocale the `ULocale` used to configure the formatter. If `ulocale` is `null`, the default `FORMAT` locale will be used. Annotations @Deprecated See Also `Category#FORMAT`

public void setLocale(ULocale ulocale)

Deprecated

ICU 50 This method clears the pattern and might create a different kind of PluralRules instance; use one of the constructors to create a new instance instead.

Sets the locale used by this PluraFormat object.

Note

Calling this method resets this PluraFormat object, i.e., a pattern that was applied previously will be removed, and the NumberFormat is set to the default number format for the locale. The resulting format behaves the same as one constructed from PluralFormat(ULocale, PluralRules.PluralType) with PluralType.CARDINAL.

Parameters

ulocale:ULocale: the ULocale used to configure the formatter. If ulocale is null, the default FORMAT locale will be used.

Annotations

@Deprecated

See Also

Category#FORMAT

setNumberFormat	back to summary
public void setNumberFormat(NumberFormat format) Sets the number format used by this formatter. You only need to call this if you want a different number format than the default formatter for the locale. Parameters format:NumberFormat the number format to use. ICU Status Stable since ICU 3.8.

setNumberFormat

back to summary

public void setNumberFormat(NumberFormat format)

Sets the number format used by this formatter. You only need to call this if you want a different number format than the default formatter for the locale.

Parameters

format:NumberFormat: the number format to use.

ICU Status

Stable since ICU 3.8.

toPattern	back to summary
public String toPattern() Returns the pattern for this PluralFormat. Returns:String the pattern string ICU Status Stable since ICU 4.2.

toPattern

back to summary

public String toPattern()

Returns the pattern for this PluralFormat.

Returns:String: the pattern string
ICU Status: Stable since ICU 4.2.

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Doc from java.lang.Object.toString. Returns a string representation of the object. Returns:String a string representation of the object. Annotations @Override ICU Status Stable since ICU 3.8.

toString

back to summary

public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object.

Returns:String

a string representation of the object.

Annotations

@Override

ICU Status

Stable since ICU 3.8.

public Class PluralFormat

The Problem of Plural Forms in Internationalized Messages

Usage of `PluralFormat`

Patterns and Their Interpretation

Defining Custom Plural Rules

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

pack-priv Interface PluralFormat.PluralSelector

Method Summary

Method Detail

private final Class PluralFormat.PluralSelectorAdapter

Constructor Summary

Method Summary

Constructor Detail

Method Detail

public Class PluralFormat

The Problem of Plural Forms in Internationalized Messages

Usage of PluralFormat

Patterns and Their Interpretation

Defining Custom Plural Rules

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

pack-priv Interface PluralFormat.PluralSelector

Method Summary

Method Detail

private final Class PluralFormat.PluralSelectorAdapter

Constructor Summary

Method Summary

Constructor Detail

Method Detail

Usage of `PluralFormat`