Class MessageFormat

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Cloneable

    public class MessageFormat
    extends UFormat
    .

    MessageFormat prepares strings for display to users, with optional arguments (variables/placeholders). The arguments can occur in any order, which is necessary for translation into languages with different grammars.

    A MessageFormat is constructed from a pattern string with arguments in {curly braces} which will be replaced by formatted values.

    MessageFormat differs from the other Format classes in that you create a MessageFormat object with one of its constructors (not with a getInstance style factory method). Factory methods aren't necessary because MessageFormat itself doesn't implement locale-specific behavior. Any locale-specific behavior is defined by the pattern that you provide and the subformats used for inserted arguments.

    Arguments can be named (using identifiers) or numbered (using small ASCII-digit integers). Some of the API methods work only with argument numbers and throw an exception if the pattern has named arguments (see usesNamedArguments()).

    An argument might not specify any format type. In this case, a Number value is formatted with a default (for the locale) NumberFormat, a Date value is formatted with a default (for the locale) DateFormat, and for any other value its toString() value is used.

    An argument might specify a "simple" type for which the specified Format object is created, cached and used.

    An argument might have a "complex" type with nested MessageFormat sub-patterns. During formatting, one of these sub-messages is selected according to the argument value and recursively formatted.

    After construction, a custom Format object can be set for a top-level argument, overriding the default formatting and parsing behavior for that argument. However, custom formatting can be achieved more simply by writing a typeless argument in the pattern string and supplying it with a preformatted string value.

    When formatting, MessageFormat takes a collection of argument values and writes an output string. The argument values may be passed as an array (when the pattern contains only numbered arguments) or as a Map (which works for both named and numbered arguments).

    Each argument is matched with one of the input values by array index or map key and formatted according to its pattern specification (or using a custom Format object if one was set). A numbered pattern argument is matched with a map key that contains that number as an ASCII-decimal-digit string (without leading zero).

    Patterns and Their Interpretation

    MessageFormat uses patterns of the following form:
     message = messageText (argument messageText)*
     argument = noneArg | simpleArg | complexArg
     complexArg = choiceArg | pluralArg | selectArg | selectordinalArg
    
     noneArg = '{' argNameOrNumber '}'
     simpleArg = '{' argNameOrNumber ',' argType [',' argStyle] '}'
     choiceArg = '{' argNameOrNumber ',' "choice" ',' choiceStyle '}'
     pluralArg = '{' argNameOrNumber ',' "plural" ',' pluralStyle '}'
     selectArg = '{' argNameOrNumber ',' "select" ',' selectStyle '}'
     selectordinalArg = '{' argNameOrNumber ',' "selectordinal" ',' pluralStyle '}'
    
     choiceStyle: see ChoiceFormat
     pluralStyle: see PluralFormat
     selectStyle: see SelectFormat
    
     argNameOrNumber = argName | argNumber
     argName = [^[[:Pattern_Syntax:][:Pattern_White_Space:]]]+
     argNumber = '0' | ('1'..'9' ('0'..'9')*)
    
     argType = "number" | "date" | "time" | "spellout" | "ordinal" | "duration"
     argStyle = "short" | "medium" | "long" | "full" | "integer" | "currency" | "percent" | argStyleText | "::" argSkeletonText
     
    • messageText can contain quoted literal strings including syntax characters. A quoted literal string begins with an ASCII apostrophe and a syntax character (usually a {curly brace}) and continues until the next single apostrophe. A double ASCII apostrophe inside or outside of a quoted string represents one literal apostrophe.
    • Quotable syntax characters are the {curly braces} in all messageText parts, plus the '#' sign in a messageText immediately inside a pluralStyle, and the '|' symbol in a messageText immediately inside a choiceStyle.
    • See also MessagePattern.ApostropheMode
    • In argStyleText, every single ASCII apostrophe begins and ends quoted literal text, and unquoted {curly braces} must occur in matched pairs.

    Recommendation: Use the real apostrophe (single quote) character \\u2019 for human-readable text, and use the ASCII apostrophe (\\u0027 ' ) only in program syntax, like quoting in MessageFormat. See the annotations for U+0027 Apostrophe in The Unicode Standard.

    The choice argument type is deprecated. Use plural arguments for proper plural selection, and select arguments for simple selection among a fixed set of choices.

    The argType and argStyle values are used to create a Format instance for the format element. The following table shows how the values map to Format instances. Combinations not shown in the table are illegal. Any argStyleText must be a valid pattern string for the Format subclass used.

    argType argStyle resulting Format object
    (none) null
    number (none) NumberFormat.getInstance(getLocale())
    integer NumberFormat.getIntegerInstance(getLocale())
    currency NumberFormat.getCurrencyInstance(getLocale())
    percent NumberFormat.getPercentInstance(getLocale())
    argStyleText new DecimalFormat(argStyleText, new DecimalFormatSymbols(getLocale()))
    argSkeletonText NumberFormatter.forSkeleton(argSkeletonText).locale(getLocale()).toFormat()
    date (none) DateFormat.getDateInstance(DateFormat.DEFAULT, getLocale())
    short DateFormat.getDateInstance(DateFormat.SHORT, getLocale())
    medium DateFormat.getDateInstance(DateFormat.DEFAULT, getLocale())
    long DateFormat.getDateInstance(DateFormat.LONG, getLocale())
    full DateFormat.getDateInstance(DateFormat.FULL, getLocale())
    argStyleText new SimpleDateFormat(argStyleText, getLocale())
    argSkeletonText DateFormat.getInstanceForSkeleton(argSkeletonText, getLocale())
    time (none) DateFormat.getTimeInstance(DateFormat.DEFAULT, getLocale())
    short DateFormat.getTimeInstance(DateFormat.SHORT, getLocale())
    medium DateFormat.getTimeInstance(DateFormat.DEFAULT, getLocale())
    long DateFormat.getTimeInstance(DateFormat.LONG, getLocale())
    full DateFormat.getTimeInstance(DateFormat.FULL, getLocale())
    argStyleText new SimpleDateFormat(argStyleText, getLocale())
    spellout argStyleText (optional) new RuleBasedNumberFormat(getLocale(), RuleBasedNumberFormat.SPELLOUT)
        .setDefaultRuleset(argStyleText);
    ordinal argStyleText (optional) new RuleBasedNumberFormat(getLocale(), RuleBasedNumberFormat.ORDINAL)
        .setDefaultRuleset(argStyleText);
    duration argStyleText (optional) new RuleBasedNumberFormat(getLocale(), RuleBasedNumberFormat.DURATION)
        .setDefaultRuleset(argStyleText);

    Differences from java.text.MessageFormat

    The ICU MessageFormat supports both named and numbered arguments, while the JDK MessageFormat only supports numbered arguments. Named arguments make patterns more readable.

    ICU implements a more user-friendly apostrophe quoting syntax. In message text, an apostrophe only begins quoting literal text if it immediately precedes a syntax character (mostly {curly braces}).
    In the JDK MessageFormat, an apostrophe always begins quoting, which requires common text like "don't" and "aujourd'hui" to be written with doubled apostrophes like "don''t" and "aujourd''hui". For more details see MessagePattern.ApostropheMode.

    ICU does not create a ChoiceFormat object for a choiceArg, pluralArg or selectArg but rather handles such arguments itself. The JDK MessageFormat does create and use a ChoiceFormat object (new ChoiceFormat(argStyleText)). The JDK does not support plural and select arguments at all.

    Both the ICU and the JDK MessageFormat can control the argument formats by using argStyle. But the JDK MessageFormat only supports predefined formats and number / date / time pattern strings (which would need to be localized).
    ICU supports everything the JDK does, and also number / date / time skeletons using the :: prefix (which automatically yield output appropriate for the MessageFormat locale).

    Argument formatting

    Arguments are formatted according to their type, using the default ICU formatters for those types, unless otherwise specified. For unknown types, MessageFormat will call toString().

    There are also several ways to control the formatting.

    We recommend you use default styles, predefined style values, skeletons, or preformatted values, but not pattern strings or custom format objects.

    For more details, see the ICU User Guide.

    Usage Information

    Here are some examples of usage:

     Object[] arguments = {
         7,
         new Date(System.currentTimeMillis()),
         "a disturbance in the Force"
     };
    
     String result = MessageFormat.format(
         "At {1,time,::jmm} on {1,date,::dMMMM}, there was {2} on planet {0,number,integer}.",
         arguments);
    
     output: At 4:34 PM on March 23, there was a disturbance
               in the Force on planet 7.
    
     
    Typically, the message format will come from resources, and the arguments will be dynamically set at runtime.

    Example 2:

     Object[] testArgs = { 3, "MyDisk" };
    
     MessageFormat form = new MessageFormat(
         "The disk \"{1}\" contains {0} file(s).");
    
     System.out.println(form.format(testArgs));
    
     // output, with different testArgs
     output: The disk "MyDisk" contains 0 file(s).
     output: The disk "MyDisk" contains 1 file(s).
     output: The disk "MyDisk" contains 1,273 file(s).
     

    For messages that include plural forms, you can use a plural argument:

     MessageFormat msgFmt = new MessageFormat(
         "{num_files, plural, " +
         "=0{There are no files on disk \"{disk_name}\".}" +
         "=1{There is one file on disk \"{disk_name}\".}" +
         "other{There are # files on disk \"{disk_name}\".}}",
         ULocale.ENGLISH);
     Map args = new HashMap();
     args.put("num_files", 0);
     args.put("disk_name", "MyDisk");
     System.out.println(msgFmt.format(args));
     args.put("num_files", 3);
     System.out.println(msgFmt.format(args));
    
     output:
     There are no files on disk "MyDisk".
     There are 3 files on "MyDisk".
     
    See PluralFormat and PluralRules for details.

    Synchronization

    MessageFormats are not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

    See Also:
    Locale, Format, NumberFormat, DecimalFormat, ChoiceFormat, PluralFormat, SelectFormat, Serialized Form
    • Constructor Summary

      Constructors 
      Constructor Description
      MessageFormat​(java.lang.String pattern)
      Constructs a MessageFormat for the default FORMAT locale and the specified pattern.
      MessageFormat​(java.lang.String pattern, ULocale locale)
      Constructs a MessageFormat for the specified locale and pattern.
      MessageFormat​(java.lang.String pattern, java.util.Locale locale)
      Constructs a MessageFormat for the specified locale and pattern.
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void applyPattern​(java.lang.String pttrn)
      Sets the pattern used by this message format.
      void applyPattern​(java.lang.String pattern, MessagePattern.ApostropheMode aposMode)
      Sets the ApostropheMode and the pattern used by this message format.
      private boolean argNameMatches​(int partIndex, java.lang.String argName, int argNumber)  
      static java.lang.String autoQuoteApostrophe​(java.lang.String pattern)
      Converts an 'apostrophe-friendly' pattern into a standard pattern.
      private void cacheExplicitFormats()  
      java.lang.Object clone()
      private java.text.Format createAppropriateFormat​(java.lang.String type, java.lang.String style)  
      (package private) java.text.Format dateTimeFormatForPatternOrSkeleton​(java.lang.String style)  
      boolean equals​(java.lang.Object obj)
      private static int findChoiceSubMessage​(MessagePattern pattern, int partIndex, double number)
      Finds the ChoiceFormat sub-message for the given number.
      private int findFirstPluralNumberArg​(int msgStart, java.lang.String argName)
      Returns the ARG_START index of the first occurrence of the plural number in a sub-message.
      private static int findKeyword​(java.lang.String s, java.lang.String[] list)  
      private int findOtherSubMessage​(int partIndex)
      Finds the "other" sub-message.
      private void format​(int msgStart, MessageFormat.PluralSelectorContext pluralNumber, java.lang.Object[] args, java.util.Map<java.lang.String,​java.lang.Object> argsMap, MessageFormat.AppendableWrapper dest, java.text.FieldPosition fp)
      Formats the arguments and writes the result into the AppendableWrapper, updates the field position.
      java.lang.StringBuffer format​(java.lang.Object[] arguments, java.lang.StringBuffer result, java.text.FieldPosition pos)
      Formats an array of objects and appends the MessageFormat's pattern, with arguments replaced by the formatted objects, to the provided StringBuffer.
      private void format​(java.lang.Object[] arguments, java.util.Map<java.lang.String,​java.lang.Object> argsMap, MessageFormat.AppendableWrapper dest, java.text.FieldPosition fp)
      Internal routine used by format.
      private void format​(java.lang.Object arguments, MessageFormat.AppendableWrapper result, java.text.FieldPosition fp)  
      java.lang.StringBuffer format​(java.lang.Object arguments, java.lang.StringBuffer result, java.text.FieldPosition pos)
      Formats a map or array of objects and appends the MessageFormat's pattern, with format elements replaced by the formatted objects, to the provided StringBuffer.
      static java.lang.String format​(java.lang.String pattern, java.lang.Object... arguments)
      Creates a MessageFormat with the given pattern and uses it to format the given arguments.
      static java.lang.String format​(java.lang.String pattern, java.util.Map<java.lang.String,​java.lang.Object> arguments)
      Creates a MessageFormat with the given pattern and uses it to format the given arguments.
      java.lang.StringBuffer format​(java.util.Map<java.lang.String,​java.lang.Object> arguments, java.lang.StringBuffer result, java.text.FieldPosition pos)
      Formats a map of objects and appends the MessageFormat's pattern, with arguments replaced by the formatted objects, to the provided StringBuffer.
      private void formatComplexSubMessage​(int msgStart, MessageFormat.PluralSelectorContext pluralNumber, java.lang.Object[] args, java.util.Map<java.lang.String,​java.lang.Object> argsMap, MessageFormat.AppendableWrapper dest)  
      java.text.AttributedCharacterIterator formatToCharacterIterator​(java.lang.Object arguments)
      Formats an array of objects and inserts them into the MessageFormat's pattern, producing an AttributedCharacterIterator.
      MessagePattern.ApostropheMode getApostropheMode()
      private java.lang.String getArgName​(int partIndex)  
      java.util.Set<java.lang.String> getArgumentNames()
      Returns the top-level argument names.
      java.text.Format getFormatByArgumentName​(java.lang.String argumentName)
      Returns the first top-level format associated with the given argument name.
      java.text.Format[] getFormats()
      Returns the Format objects used for the format elements in the previously set pattern string.
      java.text.Format[] getFormatsByArgumentIndex()
      Returns the Format objects used for the values passed into format methods or returned from parse methods.
      private java.lang.String getLiteralStringUntilNextArgument​(int from)
      Read as much literal string from the pattern string as possible.
      java.util.Locale getLocale()
      Returns the locale that's used when creating or comparing subformats.
      private DateFormat getStockDateFormatter()  
      private NumberFormat getStockNumberFormatter()  
      ULocale getULocale()
      Returns the locale that's used when creating argument Format objects.
      int hashCode()
      private static int matchStringUntilLimitPart​(MessagePattern pattern, int partIndex, int limitPartIndex, java.lang.String source, int sourceOffset)
      Matches the pattern string from the end of the partIndex to the beginning of the limitPartIndex, including all syntax except SKIP_SYNTAX, against the source string starting at sourceOffset.
      private int nextTopLevelArgStart​(int partIndex)
      Returns the part index of the next ARG_START after partIndex, or -1 if there is none more.
      private void parse​(int msgStart, java.lang.String source, java.text.ParsePosition pos, java.lang.Object[] args, java.util.Map<java.lang.String,​java.lang.Object> argsMap)
      Parses the string, filling either the Map or the Array.
      java.lang.Object[] parse​(java.lang.String source)
      Parses text from the beginning of the given string to produce an object array.
      java.lang.Object[] parse​(java.lang.String source, java.text.ParsePosition pos)
      Parses the string.
      private static double parseChoiceArgument​(MessagePattern pattern, int partIndex, java.lang.String source, java.text.ParsePosition pos)  
      java.lang.Object parseObject​(java.lang.String source, java.text.ParsePosition pos)
      Parses text from a string to produce an object array or Map.
      java.util.Map<java.lang.String,​java.lang.Object> parseToMap​(java.lang.String source)
      Parses text from the beginning of the given string to produce a map from argument to values.
      java.util.Map<java.lang.String,​java.lang.Object> parseToMap​(java.lang.String source, java.text.ParsePosition pos)
      Parses the string, returning the results in a Map.
      private void readObject​(java.io.ObjectInputStream in)
      Custom deserialization, new in ICU 4.8.
      private void resetPattern()  
      private void setArgStartFormat​(int argStart, java.text.Format formatter)
      Sets a formatter for a MessagePattern ARG_START part index.
      private void setCustomArgStartFormat​(int argStart, java.text.Format formatter)
      Sets a custom formatter for a MessagePattern ARG_START part index.
      void setFormat​(int formatElementIndex, java.text.Format newFormat)
      Sets the Format object to use for the format element with the given format element index within the previously set pattern string.
      void setFormatByArgumentIndex​(int argumentIndex, java.text.Format newFormat)
      Sets the Format object to use for the format elements within the previously set pattern string that use the given argument index.
      void setFormatByArgumentName​(java.lang.String argumentName, java.text.Format newFormat)
      Sets the Format object to use for the format elements within the previously set pattern string that use the given argument name.
      void setFormats​(java.text.Format[] newFormats)
      Sets the Format objects to use for the format elements in the previously set pattern string.
      void setFormatsByArgumentIndex​(java.text.Format[] newFormats)
      Sets the Format objects to use for the values passed into format methods or returned from parse methods.
      void setFormatsByArgumentName​(java.util.Map<java.lang.String,​java.text.Format> newFormats)
      Sets the Format objects to use for the values passed into format methods or returned from parse methods.
      void setLocale​(ULocale locale)
      Sets the locale to be used for creating argument Format objects.
      void setLocale​(java.util.Locale locale)
      Sets the locale to be used for creating argument Format objects.
      java.lang.String toPattern()
      Returns the applied pattern string.
      private java.text.FieldPosition updateMetaData​(MessageFormat.AppendableWrapper dest, int prevLength, java.text.FieldPosition fp, java.lang.Object argId)  
      boolean usesNamedArguments()
      Returns true if this MessageFormat uses named arguments, and false otherwise.
      private void writeObject​(java.io.ObjectOutputStream out)
      Custom serialization, new in ICU 4.8.
      • Methods inherited from class java.text.Format

        format, parseObject
      • Methods inherited from class java.lang.Object

        finalize, getClass, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • ulocale

        private transient ULocale ulocale
        The locale to use for formatting numbers and dates.
      • msgPattern

        private transient MessagePattern msgPattern
        The MessagePattern which contains the parsed structure of the pattern string.
      • cachedFormatters

        private transient java.util.Map<java.lang.Integer,​java.text.Format> cachedFormatters
        Cached formatters so we can just use them whenever needed instead of creating them from scratch every time.
      • customFormatArgStarts

        private transient java.util.Set<java.lang.Integer> customFormatArgStarts
        Set of ARG_START part indexes where custom, user-provided Format objects have been set via setFormat() or similar API.
      • stockDateFormatter

        private transient DateFormat stockDateFormatter
        Stock formatters. Those are used when a format is not explicitly mentioned in the message. The format is inferred from the argument.
      • stockNumberFormatter

        private transient NumberFormat stockNumberFormatter
      • typeList

        private static final java.lang.String[] typeList
      • modifierList

        private static final java.lang.String[] modifierList
      • dateModifierList

        private static final java.lang.String[] dateModifierList
      • rootLocale

        private static final java.util.Locale rootLocale
    • Constructor Detail

      • MessageFormat

        public MessageFormat​(java.lang.String pattern)
        Constructs a MessageFormat for the default FORMAT locale and the specified pattern. Sets the locale and calls applyPattern(pattern).
        Parameters:
        pattern - the pattern for this message format
        Throws:
        java.lang.IllegalArgumentException - if the pattern is invalid
        See Also:
        ULocale.Category.FORMAT
      • MessageFormat

        public MessageFormat​(java.lang.String pattern,
                             java.util.Locale locale)
        Constructs a MessageFormat for the specified locale and pattern. Sets the locale and calls applyPattern(pattern).
        Parameters:
        pattern - the pattern for this message format
        locale - the locale for this message format
        Throws:
        java.lang.IllegalArgumentException - if the pattern is invalid
      • MessageFormat

        public MessageFormat​(java.lang.String pattern,
                             ULocale locale)
        Constructs a MessageFormat for the specified locale and pattern. Sets the locale and calls applyPattern(pattern).
        Parameters:
        pattern - the pattern for this message format
        locale - the locale for this message format
        Throws:
        java.lang.IllegalArgumentException - if the pattern is invalid
    • Method Detail

      • setLocale

        public void setLocale​(java.util.Locale locale)
        Sets the locale to be used for creating argument Format objects. This affects subsequent calls to the applyPattern method as well as to the format and formatToCharacterIterator methods.
        Parameters:
        locale - the locale to be used when creating or comparing subformats
      • setLocale

        public void setLocale​(ULocale locale)
        Sets the locale to be used for creating argument Format objects. This affects subsequent calls to the applyPattern method as well as to the format and formatToCharacterIterator methods.
        Parameters:
        locale - the locale to be used when creating or comparing subformats
      • getLocale

        public java.util.Locale getLocale()
        Returns the locale that's used when creating or comparing subformats.
        Returns:
        the locale used when creating or comparing subformats
      • getULocale

        public ULocale getULocale()
        Returns the locale that's used when creating argument Format objects.
        Returns:
        the locale used when creating or comparing subformats
      • applyPattern

        public void applyPattern​(java.lang.String pttrn)
        Sets the pattern used by this message format. Parses the pattern and caches Format objects for simple argument types. Patterns and their interpretation are specified in the class description.
        Parameters:
        pttrn - the pattern for this message format
        Throws:
        java.lang.IllegalArgumentException - if the pattern is invalid
      • applyPattern

        public void applyPattern​(java.lang.String pattern,
                                 MessagePattern.ApostropheMode aposMode)
        Sets the ApostropheMode and the pattern used by this message format. Parses the pattern and caches Format objects for simple argument types. Patterns and their interpretation are specified in the class description.

        This method is best used only once on a given object to avoid confusion about the mode, and after constructing the object with an empty pattern string to minimize overhead.

        Parameters:
        pattern - the pattern for this message format
        aposMode - the new ApostropheMode
        Throws:
        java.lang.IllegalArgumentException - if the pattern is invalid
        See Also:
        MessagePattern.ApostropheMode
      • toPattern

        public java.lang.String toPattern()
        Returns the applied pattern string.
        Returns:
        the pattern string
        Throws:
        java.lang.IllegalStateException - after custom Format objects have been set via setFormat() or similar APIs
      • nextTopLevelArgStart

        private int nextTopLevelArgStart​(int partIndex)
        Returns the part index of the next ARG_START after partIndex, or -1 if there is none more.
        Parameters:
        partIndex - Part index of the previous ARG_START (initially 0).
      • argNameMatches

        private boolean argNameMatches​(int partIndex,
                                       java.lang.String argName,
                                       int argNumber)
      • getArgName

        private java.lang.String getArgName​(int partIndex)
      • setFormatsByArgumentIndex

        public void setFormatsByArgumentIndex​(java.text.Format[] newFormats)
        Sets the Format objects to use for the values passed into format methods or returned from parse methods. The indices of elements in newFormats correspond to the argument indices used in the previously set pattern string. The order of formats in newFormats thus corresponds to the order of elements in the arguments array passed to the format methods or the result array returned by the parse methods.

        If an argument index is used for more than one format element in the pattern string, then the corresponding new format is used for all such format elements. If an argument index is not used for any format element in the pattern string, then the corresponding new format is ignored. If fewer formats are provided than needed, then only the formats for argument indices less than newFormats.length are replaced. This method is only supported if the format does not use named arguments, otherwise an IllegalArgumentException is thrown.

        Parameters:
        newFormats - the new formats to use
        Throws:
        java.lang.NullPointerException - if newFormats is null
        java.lang.IllegalArgumentException - if this formatter uses named arguments
      • setFormatsByArgumentName

        public void setFormatsByArgumentName​(java.util.Map<java.lang.String,​java.text.Format> newFormats)
        Sets the Format objects to use for the values passed into format methods or returned from parse methods. The keys in newFormats are the argument names in the previously set pattern string, and the values are the formats.

        Only argument names from the pattern string are considered. Extra keys in newFormats that do not correspond to an argument name are ignored. Similarly, if there is no format in newFormats for an argument name, the formatter for that argument remains unchanged.

        This may be called on formats that do not use named arguments. In this case the map will be queried for key Strings that represent argument indices, e.g. "0", "1", "2" etc.

        Parameters:
        newFormats - a map from String to Format providing new formats for named arguments.
      • setFormats

        public void setFormats​(java.text.Format[] newFormats)
        Sets the Format objects to use for the format elements in the previously set pattern string. The order of formats in newFormats corresponds to the order of format elements in the pattern string.

        If more formats are provided than needed by the pattern string, the remaining ones are ignored. If fewer formats are provided than needed, then only the first newFormats.length formats are replaced.

        Since the order of format elements in a pattern string often changes during localization, it is generally better to use the setFormatsByArgumentIndex method, which assumes an order of formats corresponding to the order of elements in the arguments array passed to the format methods or the result array returned by the parse methods.

        Parameters:
        newFormats - the new formats to use
        Throws:
        java.lang.NullPointerException - if newFormats is null
      • setFormatByArgumentIndex

        public void setFormatByArgumentIndex​(int argumentIndex,
                                             java.text.Format newFormat)
        Sets the Format object to use for the format elements within the previously set pattern string that use the given argument index. The argument index is part of the format element definition and represents an index into the arguments array passed to the format methods or the result array returned by the parse methods.

        If the argument index is used for more than one format element in the pattern string, then the new format is used for all such format elements. If the argument index is not used for any format element in the pattern string, then the new format is ignored. This method is only supported when exclusively numbers are used for argument names. Otherwise an IllegalArgumentException is thrown.

        Parameters:
        argumentIndex - the argument index for which to use the new format
        newFormat - the new format to use
        Throws:
        java.lang.IllegalArgumentException - if this format uses named arguments
      • setFormatByArgumentName

        public void setFormatByArgumentName​(java.lang.String argumentName,
                                            java.text.Format newFormat)
        Sets the Format object to use for the format elements within the previously set pattern string that use the given argument name.

        If the argument name is used for more than one format element in the pattern string, then the new format is used for all such format elements. If the argument name is not used for any format element in the pattern string, then the new format is ignored.

        This API may be used on formats that do not use named arguments. In this case argumentName should be a String that names an argument index, e.g. "0", "1", "2"... etc. If it does not name a valid index, the format will be ignored. No error is thrown.

        Parameters:
        argumentName - the name of the argument to change
        newFormat - the new format to use
      • setFormat

        public void setFormat​(int formatElementIndex,
                              java.text.Format newFormat)
        Sets the Format object to use for the format element with the given format element index within the previously set pattern string. The format element index is the zero-based number of the format element counting from the start of the pattern string.

        Since the order of format elements in a pattern string often changes during localization, it is generally better to use the setFormatByArgumentIndex method, which accesses format elements based on the argument index they specify.

        Parameters:
        formatElementIndex - the index of a format element within the pattern
        newFormat - the format to use for the specified format element
        Throws:
        java.lang.ArrayIndexOutOfBoundsException - if formatElementIndex is equal to or larger than the number of format elements in the pattern string
      • getFormatsByArgumentIndex

        public java.text.Format[] getFormatsByArgumentIndex()
        Returns the Format objects used for the values passed into format methods or returned from parse methods. The indices of elements in the returned array correspond to the argument indices used in the previously set pattern string. The order of formats in the returned array thus corresponds to the order of elements in the arguments array passed to the format methods or the result array returned by the parse methods.

        If an argument index is used for more than one format element in the pattern string, then the format used for the last such format element is returned in the array. If an argument index is not used for any format element in the pattern string, then null is returned in the array. This method is only supported when exclusively numbers are used for argument names. Otherwise an IllegalArgumentException is thrown.

        Returns:
        the formats used for the arguments within the pattern
        Throws:
        java.lang.IllegalArgumentException - if this format uses named arguments
      • getFormats

        public java.text.Format[] getFormats()
        Returns the Format objects used for the format elements in the previously set pattern string. The order of formats in the returned array corresponds to the order of format elements in the pattern string.

        Since the order of format elements in a pattern string often changes during localization, it's generally better to use the getFormatsByArgumentIndex() method, which assumes an order of formats corresponding to the order of elements in the arguments array passed to the format methods or the result array returned by the parse methods. This method is only supported when exclusively numbers are used for argument names. Otherwise an IllegalArgumentException is thrown.

        Returns:
        the formats used for the format elements in the pattern
        Throws:
        java.lang.IllegalArgumentException - if this format uses named arguments
      • getArgumentNames

        public java.util.Set<java.lang.String> getArgumentNames()
        Returns the top-level argument names. For more details, see setFormatByArgumentName(String, Format).
        Returns:
        a Set of argument names
      • getFormatByArgumentName

        public java.text.Format getFormatByArgumentName​(java.lang.String argumentName)
        Returns the first top-level format associated with the given argument name. For more details, see setFormatByArgumentName(String, Format).
        Parameters:
        argumentName - The name of the desired argument.
        Returns:
        the Format associated with the name, or null if there isn't one.
      • format

        public final java.lang.StringBuffer format​(java.lang.Object[] arguments,
                                                   java.lang.StringBuffer result,
                                                   java.text.FieldPosition pos)
        Formats an array of objects and appends the MessageFormat's pattern, with arguments replaced by the formatted objects, to the provided StringBuffer.

        The text substituted for the individual format elements is derived from the current subformat of the format element and the arguments element at the format element's argument index as indicated by the first matching line of the following table. An argument is unavailable if arguments is null or has fewer than argumentIndex+1 elements. When an argument is unavailable no substitution is performed.

        argType or Format value object Formatted Text
        any unavailable "{" + argNameOrNumber + "}"
        any null "null"
        custom Format != null any customFormat.format(argument)
        noneArg, or custom Format == null instanceof Number NumberFormat.getInstance(getLocale()).format(argument)
        noneArg, or custom Format == null instanceof Date DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT, getLocale()).format(argument)
        noneArg, or custom Format == null instanceof String argument
        noneArg, or custom Format == null any argument.toString()
        complexArg any result of recursive formatting of a selected sub-message

        If pos is non-null, and refers to Field.ARGUMENT, the location of the first formatted string will be returned. This method is only supported when the format does not use named arguments, otherwise an IllegalArgumentException is thrown.

        Parameters:
        arguments - an array of objects to be formatted and substituted.
        result - where text is appended.
        pos - On input: an alignment field, if desired. On output: the offsets of the alignment field.
        Throws:
        java.lang.IllegalArgumentException - if a value in the arguments array is not of the type expected by the corresponding argument or custom Format object.
        java.lang.IllegalArgumentException - if this format uses named arguments
      • format

        public final java.lang.StringBuffer format​(java.util.Map<java.lang.String,​java.lang.Object> arguments,
                                                   java.lang.StringBuffer result,
                                                   java.text.FieldPosition pos)
        Formats a map of objects and appends the MessageFormat's pattern, with arguments replaced by the formatted objects, to the provided StringBuffer.

        The text substituted for the individual format elements is derived from the current subformat of the format element and the arguments value corresponding to the format element's argument name.

        A numbered pattern argument is matched with a map key that contains that number as an ASCII-decimal-digit string (without leading zero).

        An argument is unavailable if arguments is null or does not have a value corresponding to an argument name in the pattern. When an argument is unavailable no substitution is performed.

        Parameters:
        arguments - a map of objects to be formatted and substituted.
        result - where text is appended.
        pos - On input: an alignment field, if desired. On output: the offsets of the alignment field.
        Returns:
        the passed-in StringBuffer
        Throws:
        java.lang.IllegalArgumentException - if a value in the arguments array is not of the type expected by the corresponding argument or custom Format object.
      • format

        public static java.lang.String format​(java.lang.String pattern,
                                              java.lang.Object... arguments)
        Creates a MessageFormat with the given pattern and uses it to format the given arguments. This is equivalent to
        (new MessageFormat(pattern)).format(arguments, new StringBuffer(), null).toString()
        Throws:
        java.lang.IllegalArgumentException - if the pattern is invalid
        java.lang.IllegalArgumentException - if a value in the arguments array is not of the type expected by the corresponding argument or custom Format object.
        java.lang.IllegalArgumentException - if this format uses named arguments
      • format

        public static java.lang.String format​(java.lang.String pattern,
                                              java.util.Map<java.lang.String,​java.lang.Object> arguments)
        Creates a MessageFormat with the given pattern and uses it to format the given arguments. The pattern must identifyarguments by name instead of by number.

        Throws:
        java.lang.IllegalArgumentException - if the pattern is invalid
        java.lang.IllegalArgumentException - if a value in the arguments array is not of the type expected by the corresponding argument or custom Format object.
        See Also:
        format(Map, StringBuffer, FieldPosition), format(String, Object[])
      • usesNamedArguments

        public boolean usesNamedArguments()
        Returns true if this MessageFormat uses named arguments, and false otherwise. See class description.
        Returns:
        true if named arguments are used.
      • format

        public final java.lang.StringBuffer format​(java.lang.Object arguments,
                                                   java.lang.StringBuffer result,
                                                   java.text.FieldPosition pos)
        Formats a map or array of objects and appends the MessageFormat's pattern, with format elements replaced by the formatted objects, to the provided StringBuffer. This is equivalent to either of
        format((Object[]) arguments, result, pos) format((Map) arguments, result, pos)
        A map must be provided if this format uses named arguments, otherwise an IllegalArgumentException will be thrown.
        Specified by:
        format in class java.text.Format
        Parameters:
        arguments - a map or array of objects to be formatted
        result - where text is appended
        pos - On input: an alignment field, if desired On output: the offsets of the alignment field
        Throws:
        java.lang.IllegalArgumentException - if an argument in arguments is not of the type expected by the format element(s) that use it
        java.lang.IllegalArgumentException - if arguments is an array of Object and this format uses named arguments
      • formatToCharacterIterator

        public java.text.AttributedCharacterIterator formatToCharacterIterator​(java.lang.Object arguments)
        Formats an array of objects and inserts them into the MessageFormat's pattern, producing an AttributedCharacterIterator. You can use the returned AttributedCharacterIterator to build the resulting String, as well as to determine information about the resulting String.

        The text of the returned AttributedCharacterIterator is the same that would be returned by

        format(arguments, new StringBuffer(), null).toString()

        In addition, the AttributedCharacterIterator contains at least attributes indicating where text was generated from an argument in the arguments array. The keys of these attributes are of type MessageFormat.Field, their values are Integer objects indicating the index in the arguments array of the argument from which the text was generated.

        The attributes/value from the underlying Format instances that MessageFormat uses will also be placed in the resulting AttributedCharacterIterator. This allows you to not only find where an argument is placed in the resulting String, but also which fields it contains in turn.

        Overrides:
        formatToCharacterIterator in class java.text.Format
        Parameters:
        arguments - an array of objects to be formatted and substituted.
        Returns:
        AttributedCharacterIterator describing the formatted value.
        Throws:
        java.lang.NullPointerException - if arguments is null.
        java.lang.IllegalArgumentException - if a value in the arguments array is not of the type expected by the corresponding argument or custom Format object.
      • parse

        public java.lang.Object[] parse​(java.lang.String source,
                                        java.text.ParsePosition pos)
        Parses the string.

        Caveats: The parse may fail in a number of circumstances. For example:

        • If one of the arguments does not occur in the pattern.
        • If the format of an argument loses information, such as with a choice format where a large number formats to "many".
        • Does not yet handle recursion (where the substituted strings contain {n} references.)
        • Will not always find a match (or the correct match) if some part of the parse is ambiguous. For example, if the pattern "{1},{2}" is used with the string arguments {"a,b", "c"}, it will format as "a,b,c". When the result is parsed, it will return {"a", "b,c"}.
        • If a single argument is parsed more than once in the string, then the later parse wins.
        When the parse fails, use ParsePosition.getErrorIndex() to find out where in the string did the parsing failed. The returned error index is the starting offset of the sub-patterns that the string is comparing with. For example, if the parsing string "AAA {0} BBB" is comparing against the pattern "AAD {0} BBB", the error index is 0. When an error occurs, the call to this method will return null. If the source is null, return an empty array.
        Throws:
        java.lang.IllegalArgumentException - if this format uses named arguments
      • parseToMap

        public java.util.Map<java.lang.String,​java.lang.Object> parseToMap​(java.lang.String source,
                                                                                 java.text.ParsePosition pos)
        Parses the string, returning the results in a Map. This is similar to the version that returns an array of Object. This supports both named and numbered arguments-- if numbered, the keys in the map are the corresponding ASCII-decimal-digit strings (e.g. "0", "1", "2"...).
        Parameters:
        source - the text to parse
        pos - the position at which to start parsing. on return, contains the result of the parse.
        Returns:
        a Map containing key/value pairs for each parsed argument.
      • parse

        public java.lang.Object[] parse​(java.lang.String source)
                                 throws java.text.ParseException
        Parses text from the beginning of the given string to produce an object array. The method may not use the entire text of the given string.

        See the parse(String, ParsePosition) method for more information on message parsing.

        Parameters:
        source - A String whose beginning should be parsed.
        Returns:
        An Object array parsed from the string.
        Throws:
        java.text.ParseException - if the beginning of the specified string cannot be parsed.
        java.lang.IllegalArgumentException - if this format uses named arguments
      • parse

        private void parse​(int msgStart,
                           java.lang.String source,
                           java.text.ParsePosition pos,
                           java.lang.Object[] args,
                           java.util.Map<java.lang.String,​java.lang.Object> argsMap)
        Parses the string, filling either the Map or the Array. This is a private method that all the public parsing methods call. This supports both named and numbered arguments-- if numbered, the keys in the map are the corresponding ASCII-decimal-digit strings (e.g. "0", "1", "2"...).
        Parameters:
        msgStart - index in the message pattern to start from.
        source - the text to parse
        pos - the position at which to start parsing. on return, contains the result of the parse.
        args - if not null, the parse results will be filled here (The pattern has to have numbered arguments in order for this to not be null).
        argsMap - if not null, the parse results will be filled here.
      • parseToMap

        public java.util.Map<java.lang.String,​java.lang.Object> parseToMap​(java.lang.String source)
                                                                          throws java.text.ParseException
        Parses text from the beginning of the given string to produce a map from argument to values. The method may not use the entire text of the given string.

        See the parse(String, ParsePosition) method for more information on message parsing.

        Parameters:
        source - A String whose beginning should be parsed.
        Returns:
        A Map parsed from the string.
        Throws:
        java.text.ParseException - if the beginning of the specified string cannot be parsed.
        See Also:
        parseToMap(String, ParsePosition)
      • parseObject

        public java.lang.Object parseObject​(java.lang.String source,
                                            java.text.ParsePosition pos)
        Parses text from a string to produce an object array or Map.

        The method attempts to parse text starting at the index given by pos. If parsing succeeds, then the index of pos is updated to the index after the last character used (parsing does not necessarily use all characters up to the end of the string), and the parsed object array is returned. The updated pos can be used to indicate the starting point for the next call to this method. If an error occurs, then the index of pos is not changed, the error index of pos is set to the index of the character where the error occurred, and null is returned.

        See the parse(String, ParsePosition) method for more information on message parsing.

        Specified by:
        parseObject in class java.text.Format
        Parameters:
        source - A String, part of which should be parsed.
        pos - A ParsePosition object with index and error index information as described above.
        Returns:
        An Object parsed from the string, either an array of Object, or a Map, depending on whether named arguments are used. This can be queried using usesNamedArguments. In case of error, returns null.
        Throws:
        java.lang.NullPointerException - if pos is null.
      • clone

        public java.lang.Object clone()
        Overrides:
        clone in class java.text.Format
      • equals

        public boolean equals​(java.lang.Object obj)
        Overrides:
        equals in class java.lang.Object
      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object
      • getStockDateFormatter

        private DateFormat getStockDateFormatter()
      • getStockNumberFormatter

        private NumberFormat getStockNumberFormatter()
      • format

        private void format​(int msgStart,
                            MessageFormat.PluralSelectorContext pluralNumber,
                            java.lang.Object[] args,
                            java.util.Map<java.lang.String,​java.lang.Object> argsMap,
                            MessageFormat.AppendableWrapper dest,
                            java.text.FieldPosition fp)
        Formats the arguments and writes the result into the AppendableWrapper, updates the field position.

        Exactly one of args and argsMap must be null, the other non-null.

        Parameters:
        msgStart - Index to msgPattern part to start formatting from.
        pluralNumber - null except when formatting a plural argument sub-message where a '#' is replaced by the format string for this number.
        args - The formattable objects array. Non-null iff numbered values are used.
        argsMap - The key-value map of formattable objects. Non-null iff named values are used.
        dest - Output parameter to receive the result. The result (string & attributes) is appended to existing contents.
        fp - Field position status.
      • getLiteralStringUntilNextArgument

        private java.lang.String getLiteralStringUntilNextArgument​(int from)
        Read as much literal string from the pattern string as possible. This stops as soon as it finds an argument, or it reaches the end of the string.
        Parameters:
        from - Index in the pattern string to start from.
        Returns:
        A substring from the pattern string representing the longest possible substring with no arguments.
      • updateMetaData

        private java.text.FieldPosition updateMetaData​(MessageFormat.AppendableWrapper dest,
                                                       int prevLength,
                                                       java.text.FieldPosition fp,
                                                       java.lang.Object argId)
      • findChoiceSubMessage

        private static int findChoiceSubMessage​(MessagePattern pattern,
                                                int partIndex,
                                                double number)
        Finds the ChoiceFormat sub-message for the given number.
        Parameters:
        pattern - A MessagePattern.
        partIndex - the index of the first ChoiceFormat argument style part.
        number - a number to be mapped to one of the ChoiceFormat argument's intervals
        Returns:
        the sub-message start part index.
      • parseChoiceArgument

        private static double parseChoiceArgument​(MessagePattern pattern,
                                                  int partIndex,
                                                  java.lang.String source,
                                                  java.text.ParsePosition pos)
      • matchStringUntilLimitPart

        private static int matchStringUntilLimitPart​(MessagePattern pattern,
                                                     int partIndex,
                                                     int limitPartIndex,
                                                     java.lang.String source,
                                                     int sourceOffset)
        Matches the pattern string from the end of the partIndex to the beginning of the limitPartIndex, including all syntax except SKIP_SYNTAX, against the source string starting at sourceOffset. If they match, returns the length of the source string match. Otherwise returns -1.
      • findOtherSubMessage

        private int findOtherSubMessage​(int partIndex)
        Finds the "other" sub-message.
        Parameters:
        partIndex - the index of the first PluralFormat argument style part.
        Returns:
        the "other" sub-message start part index.
      • findFirstPluralNumberArg

        private int findFirstPluralNumberArg​(int msgStart,
                                             java.lang.String argName)
        Returns the ARG_START index of the first occurrence of the plural number in a sub-message. Returns -1 if it is a REPLACE_NUMBER. Returns 0 if there is neither.
      • format

        private void format​(java.lang.Object[] arguments,
                            java.util.Map<java.lang.String,​java.lang.Object> argsMap,
                            MessageFormat.AppendableWrapper dest,
                            java.text.FieldPosition fp)
        Internal routine used by format.
        Throws:
        java.lang.IllegalArgumentException - if an argument in the arguments map is not of the type expected by the format element(s) that use it.
      • resetPattern

        private void resetPattern()
      • dateTimeFormatForPatternOrSkeleton

        java.text.Format dateTimeFormatForPatternOrSkeleton​(java.lang.String style)
      • createAppropriateFormat

        private java.text.Format createAppropriateFormat​(java.lang.String type,
                                                         java.lang.String style)
      • findKeyword

        private static final int findKeyword​(java.lang.String s,
                                             java.lang.String[] list)
      • writeObject

        private void writeObject​(java.io.ObjectOutputStream out)
                          throws java.io.IOException
        Custom serialization, new in ICU 4.8. We do not want to use default serialization because we only have a small amount of persistent state which is better expressed explicitly rather than via writing field objects.
        Parameters:
        out - The output stream.
        Throws:
        java.io.IOException
      • readObject

        private void readObject​(java.io.ObjectInputStream in)
                         throws java.io.IOException,
                                java.lang.ClassNotFoundException
        Custom deserialization, new in ICU 4.8. See comments on writeObject().
        Throws:
        java.io.InvalidObjectException - if the objects read from the stream is invalid.
        java.io.IOException
        java.lang.ClassNotFoundException
      • cacheExplicitFormats

        private void cacheExplicitFormats()
      • setArgStartFormat

        private void setArgStartFormat​(int argStart,
                                       java.text.Format formatter)
        Sets a formatter for a MessagePattern ARG_START part index.
      • setCustomArgStartFormat

        private void setCustomArgStartFormat​(int argStart,
                                             java.text.Format formatter)
        Sets a custom formatter for a MessagePattern ARG_START part index. "Custom" formatters are provided by the user via setFormat() or similar APIs.
      • autoQuoteApostrophe

        public static java.lang.String autoQuoteApostrophe​(java.lang.String pattern)
        Converts an 'apostrophe-friendly' pattern into a standard pattern. This is obsolete for ICU 4.8 and higher MessageFormat pattern strings. It can still be useful together with MessageFormat.

        See the class description for more about apostrophes and quoting, and differences between ICU and MessageFormat.

        MessageFormat and ICU 4.6 and earlier MessageFormat treat all ASCII apostrophes as quotes, which is problematic in some languages, e.g. French, where apostrophe is commonly used. This utility assumes that only an unpaired apostrophe immediately before a brace is a true quote. Other unpaired apostrophes are paired, and the resulting standard pattern string is returned.

        Note: It is not guaranteed that the returned pattern is indeed a valid pattern. The only effect is to convert between patterns having different quoting semantics.

        Note: This method only works on top-level messageText, not messageText nested inside a complexArg.

        Parameters:
        pattern - the 'apostrophe-friendly' pattern to convert
        Returns:
        the standard equivalent of the original pattern