// © 2016 and later: Unicode, Inc. and others. // License & terms of use: http://www.unicode.org/copyright.html /* * Copyright (C) 2007-2013, International Business Machines Corporation and * others. All Rights Reserved. ******************************************************************************** * * File MSGFMT.H * * Modification History: * * Date Name Description * 02/19/97 aliu Converted from java. * 03/20/97 helena Finished first cut of implementation. * 07/22/98 stephen Removed operator!= (defined in Format) * 08/19/2002 srl Removing Javaisms *******************************************************************************/ #ifndef MSGFMT_H #define MSGFMT_H #include "unicode/utypes.h" #if U_SHOW_CPLUSPLUS_API /** * \file * \brief C++ API: Formats messages in a language-neutral way. */ #if !UCONFIG_NO_FORMATTING #include "unicode/format.h" #include "unicode/locid.h" #include "unicode/messagepattern.h" #include "unicode/parseerr.h" #include "unicode/plurfmt.h" #include "unicode/plurrule.h" U_CDECL_BEGIN // Forward declaration. struct UHashtable; typedef struct UHashtable UHashtable; /**< @internal */ U_CDECL_END U_NAMESPACE_BEGIN class AppendableWrapper; class DateFormat; class NumberFormat; /** * <p>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. * * <p>A MessageFormat is constructed from a <em>pattern</em> string * with arguments in {curly braces} which will be replaced by formatted values. * * <p><code>MessageFormat</code> differs from the other <code>Format</code> * classes in that you create a <code>MessageFormat</code> object with one * of its constructors (not with a <code>createInstance</code> style factory * method). Factory methods aren't necessary because <code>MessageFormat</code> * 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. * * <p>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 {@link #usesNamedArguments()}). * * <p>An argument might not specify any format type. In this case, * a numeric value is formatted with a default (for the locale) NumberFormat, * and a date/time value is formatted with a default (for the locale) DateFormat. * * <p>An argument might specify a "simple" type for which the specified * Format object is created, cached and used. * * <p>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. * * <p>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. * * <p>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 an array of names and and an array of arguments (which works for both named * and numbered arguments). * * <p>Each argument is matched with one of the input values by array index or argument name * and formatted according to its pattern specification * (or using a custom Format object if one was set). * A numbered pattern argument is matched with an argument name that contains that number * as an ASCII-decimal-digit string (without leading zero). * * <h4><a name="patterns">Patterns and Their Interpretation</a></h4> * * <code>MessageFormat</code> uses patterns of the following form: * <pre> * 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 {@link ChoiceFormat} * pluralStyle: see {@link PluralFormat} * selectStyle: see {@link 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 * </pre> * * <ul> * <li>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 apostrohpe inside or outside of a quoted string represents * one literal apostrophe. * <li>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. * <li>See also {@link #UMessagePatternApostropheMode} * <li>In argStyleText, every single ASCII apostrophe begins and ends quoted literal text, * and unquoted {curly braces} must occur in matched pairs. * </ul> * * <p>Recommendation: Use the real apostrophe (single quote) character * \htmlonly’\endhtmlonly (U+2019) for * human-readable text, and use the ASCII apostrophe ' (U+0027) * only in program syntax, like quoting in MessageFormat. * See the annotations for U+0027 Apostrophe in The Unicode Standard. * * <p>The <code>choice</code> argument type is deprecated. * Use <code>plural</code> arguments for proper plural selection, * and <code>select</code> arguments for simple selection among a fixed set of choices. * * <p>The <code>argType</code> and <code>argStyle</code> values are used to create * a <code>Format</code> 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 <code>argStyleText</code> must * be a valid pattern string for the Format subclass used. * * <p><table border=1> * <tr> * <th>argType * <th>argStyle * <th>resulting Format object * <tr> * <td colspan=2><i>(none)</i> * <td><code>null</code> * <tr> * <td rowspan=6><code>number</code> * <td><i>(none)</i> * <td><code>NumberFormat.createInstance(getLocale(), status)</code> * <tr> * <td><code>integer</code> * <td><code>NumberFormat.createInstance(getLocale(), kNumberStyle, status)</code> * <tr> * <td><code>currency</code> * <td><code>NumberFormat.createCurrencyInstance(getLocale(), status)</code> * <tr> * <td><code>percent</code> * <td><code>NumberFormat.createPercentInstance(getLocale(), status)</code> * <tr> * <td><i>argStyleText</i> * <td><code>new DecimalFormat(argStyleText, new DecimalFormatSymbols(getLocale(), status), status)</code> * <tr> * <td><i>argSkeletonText</i> * <td><code>NumberFormatter::forSkeleton(argSkeletonText, status).locale(getLocale()).toFormat(status)</code> * <tr> * <td rowspan=7><code>date</code> * <td><i>(none)</i> * <td><code>DateFormat.createDateInstance(kDefault, getLocale(), status)</code> * <tr> * <td><code>short</code> * <td><code>DateFormat.createDateInstance(kShort, getLocale(), status)</code> * <tr> * <td><code>medium</code> * <td><code>DateFormat.createDateInstance(kDefault, getLocale(), status)</code> * <tr> * <td><code>long</code> * <td><code>DateFormat.createDateInstance(kLong, getLocale(), status)</code> * <tr> * <td><code>full</code> * <td><code>DateFormat.createDateInstance(kFull, getLocale(), status)</code> * <tr> * <td><i>argStyleText</i> * <td><code>new SimpleDateFormat(argStyleText, getLocale(), status)</code> * <tr> * <td><i>argSkeletonText</i> * <td><code>DateFormat::createInstanceForSkeleton(argSkeletonText, getLocale(), status)</code> * <tr> * <td rowspan=6><code>time</code> * <td><i>(none)</i> * <td><code>DateFormat.createTimeInstance(kDefault, getLocale(), status)</code> * <tr> * <td><code>short</code> * <td><code>DateFormat.createTimeInstance(kShort, getLocale(), status)</code> * <tr> * <td><code>medium</code> * <td><code>DateFormat.createTimeInstance(kDefault, getLocale(), status)</code> * <tr> * <td><code>long</code> * <td><code>DateFormat.createTimeInstance(kLong, getLocale(), status)</code> * <tr> * <td><code>full</code> * <td><code>DateFormat.createTimeInstance(kFull, getLocale(), status)</code> * <tr> * <td><i>argStyleText</i> * <td><code>new SimpleDateFormat(argStyleText, getLocale(), status)</code> * <tr> * <td><code>spellout</code> * <td><i>argStyleText (optional)</i> * <td><code>new RuleBasedNumberFormat(URBNF_SPELLOUT, getLocale(), status) * <br/> .setDefaultRuleset(argStyleText, status);</code> * <tr> * <td><code>ordinal</code> * <td><i>argStyleText (optional)</i> * <td><code>new RuleBasedNumberFormat(URBNF_ORDINAL, getLocale(), status) * <br/> .setDefaultRuleset(argStyleText, status);</code> * <tr> * <td><code>duration</code> * <td><i>argStyleText (optional)</i> * <td><code>new RuleBasedNumberFormat(URBNF_DURATION, getLocale(), status) * <br/> .setDefaultRuleset(argStyleText, status);</code> * </table> * <p> * * <h4>Argument formatting</h4> * * <p>Arguments are formatted according to their type, using the default * ICU formatters for those types, unless otherwise specified.</p> * * <p>There are also several ways to control the formatting.</p> * * <p>We recommend you use default styles, predefined style values, skeletons, * or preformatted values, but not pattern strings or custom format objects.</p> * * <p>For more details, see the * <a href="http://userguide.icu-project.org/formatparse/messages">ICU User Guide</a>.</p> * * <h4>Usage Information</h4> * * <p>Here are some examples of usage: * Example 1: * * <pre> * \code * UErrorCode success = U_ZERO_ERROR; * GregorianCalendar cal(success); * Formattable arguments[] = { * 7L, * Formattable( (Date) cal.getTime(success), Formattable::kIsDate), * "a disturbance in the Force" * }; * * UnicodeString result; * MessageFormat::format( * "At {1,time,::jmm} on {1,date,::dMMMM}, there was {2} on planet {0,number}.", * arguments, 3, result, success ); * * cout << "result: " << result << endl; * //<output>: At 4:34 PM on March 23, there was a disturbance * // in the Force on planet 7. * \endcode * </pre> * * Typically, the message format will come from resources, and the * arguments will be dynamically set at runtime. * * <p>Example 2: * * <pre> * \code * success = U_ZERO_ERROR; * Formattable testArgs[] = {3L, "MyDisk"}; * * MessageFormat form( * "The disk \"{1}\" contains {0} file(s).", success ); * * UnicodeString string; * FieldPosition fpos = 0; * cout << "format: " << form.format(testArgs, 2, string, fpos, success ) << endl; * * // 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). * \endcode * </pre> * * * <p>For messages that include plural forms, you can use a plural argument: * <pre> * \code * success = U_ZERO_ERROR; * MessageFormat msgFmt( * "{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}\".}}", * Locale("en"), * success); * FieldPosition fpos = 0; * Formattable testArgs[] = {0L, "MyDisk"}; * UnicodeString testArgsNames[] = {"num_files", "disk_name"}; * UnicodeString result; * cout << msgFmt.format(testArgs, testArgsNames, 2, result, fpos, 0, success); * testArgs[0] = 3L; * cout << msgFmt.format(testArgs, testArgsNames, 2, result, fpos, 0, success); * \endcode * <em>output</em>: * There are no files on disk "MyDisk". * There are 3 files on "MyDisk". * </pre> * See {@link PluralFormat} and {@link PluralRules} for details. * * <h4><a name="synchronization">Synchronization</a></h4> * * <p>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. * * @stable ICU 2.0 */ class U_I18N_API MessageFormat : public Format { public: #ifndef U_HIDE_OBSOLETE_API /** * Enum type for kMaxFormat. * @obsolete ICU 3.0. The 10-argument limit was removed as of ICU 2.6, * rendering this enum type obsolete. */ enum EFormatNumber { /** * The maximum number of arguments. * @obsolete ICU 3.0. The 10-argument limit was removed as of ICU 2.6, * rendering this constant obsolete. */ kMaxFormat = 10 }; #endif /* U_HIDE_OBSOLETE_API */ /** * Constructs a new MessageFormat using the given pattern and the * default locale. * * @param pattern Pattern used to construct object. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @stable ICU 2.0 */ MessageFormat(const UnicodeString& pattern, UErrorCode &status); /** * Constructs a new MessageFormat using the given pattern and locale. * @param pattern Pattern used to construct object. * @param newLocale The locale to use for formatting dates and numbers. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @stable ICU 2.0 */ MessageFormat(const UnicodeString& pattern, const Locale& newLocale, UErrorCode& status); /** * Constructs a new MessageFormat using the given pattern and locale. * @param pattern Pattern used to construct object. * @param newLocale The locale to use for formatting dates and numbers. * @param parseError Struct to receive information on the position * of an error within the pattern. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @stable ICU 2.0 */ MessageFormat(const UnicodeString& pattern, const Locale& newLocale, UParseError& parseError, UErrorCode& status); /** * Constructs a new MessageFormat from an existing one. * @stable ICU 2.0 */ MessageFormat(const MessageFormat&); /** * Assignment operator. * @stable ICU 2.0 */ const MessageFormat& operator=(const MessageFormat&); /** * Destructor. * @stable ICU 2.0 */ virtual ~MessageFormat(); /** * Clones this Format object polymorphically. The caller owns the * result and should delete it when done. * @stable ICU 2.0 */ virtual MessageFormat* clone() const; /** * Returns true if the given Format objects are semantically equal. * Objects of different subclasses are considered unequal. * @param other the object to be compared with. * @return true if the given Format objects are semantically equal. * @stable ICU 2.0 */ virtual UBool operator==(const Format& other) const; /** * Sets the locale to be used for creating argument Format objects. * @param theLocale the new locale value to be set. * @stable ICU 2.0 */ virtual void setLocale(const Locale& theLocale); /** * Gets the locale used for creating argument Format objects. * format information. * @return the locale of the object. * @stable ICU 2.0 */ virtual const Locale& getLocale(void) const; /** * Applies the given pattern string to this message format. * * @param pattern The pattern to be applied. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @stable ICU 2.0 */ virtual void applyPattern(const UnicodeString& pattern, UErrorCode& status); /** * Applies the given pattern string to this message format. * * @param pattern The pattern to be applied. * @param parseError Struct to receive information on the position * of an error within the pattern. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @stable ICU 2.0 */ virtual void applyPattern(const UnicodeString& pattern, UParseError& parseError, UErrorCode& status); /** * Sets the UMessagePatternApostropheMode 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 * <a href="#patterns">class description</a>. * <p> * 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. * * @param pattern The pattern to be applied. * @param aposMode The new apostrophe mode. * @param parseError Struct to receive information on the position * of an error within the pattern. * Can be NULL. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @stable ICU 4.8 */ virtual void applyPattern(const UnicodeString& pattern, UMessagePatternApostropheMode aposMode, UParseError* parseError, UErrorCode& status); /** * @return this instance's UMessagePatternApostropheMode. * @stable ICU 4.8 */ UMessagePatternApostropheMode getApostropheMode() const { return msgPattern.getApostropheMode(); } /** * Returns a pattern that can be used to recreate this object. * * @param appendTo Output parameter to receive the pattern. * Result is appended to existing contents. * @return Reference to 'appendTo' parameter. * @stable ICU 2.0 */ virtual UnicodeString& toPattern(UnicodeString& appendTo) const; /** * Sets subformats. * See the class description about format numbering. * The caller should not delete the Format objects after this call. * <EM>The array formatsToAdopt is not itself adopted.</EM> Its * ownership is retained by the caller. If the call fails because * memory cannot be allocated, then the formats will be deleted * by this method, and this object will remain unchanged. * * <p>If this format uses named arguments, the new formats are discarded * and this format remains unchanged. * * @stable ICU 2.0 * @param formatsToAdopt the format to be adopted. * @param count the size of the array. */ virtual void adoptFormats(Format** formatsToAdopt, int32_t count); /** * Sets subformats. * See the class description about format numbering. * Each item in the array is cloned into the internal array. * If the call fails because memory cannot be allocated, then this * object will remain unchanged. * * <p>If this format uses named arguments, the new formats are discarded * and this format remains unchanged. * * @stable ICU 2.0 * @param newFormats the new format to be set. * @param cnt the size of the array. */ virtual void setFormats(const Format** newFormats, int32_t cnt); /** * Sets one subformat. * See the class description about format numbering. * The caller should not delete the Format object after this call. * If the number is over the number of formats already set, * the item will be deleted and ignored. * * <p>If this format uses named arguments, the new format is discarded * and this format remains unchanged. * * @stable ICU 2.0 * @param formatNumber index of the subformat. * @param formatToAdopt the format to be adopted. */ virtual void adoptFormat(int32_t formatNumber, Format* formatToAdopt); /** * Sets one subformat. * See the class description about format numbering. * If the number is over the number of formats already set, * the item will be ignored. * @param formatNumber index of the subformat. * @param format the format to be set. * @stable ICU 2.0 */ virtual void setFormat(int32_t formatNumber, const Format& format); /** * Gets format names. This function returns formatNames in StringEnumerations * which can be used with getFormat() and setFormat() to export formattable * array from current MessageFormat to another. It is the caller's responsibility * to delete the returned formatNames. * @param status output param set to success/failure code. * @stable ICU 4.0 */ virtual StringEnumeration* getFormatNames(UErrorCode& status); /** * Gets subformat pointer for given format name. * This function supports both named and numbered * arguments. If numbered, the formatName is the * corresponding UnicodeStrings (e.g. "0", "1", "2"...). * The returned Format object should not be deleted by the caller, * nor should the ponter of other object . The pointer and its * contents remain valid only until the next call to any method * of this class is made with this object. * @param formatName the name or number specifying a format * @param status output param set to success/failure code. * @stable ICU 4.0 */ virtual Format* getFormat(const UnicodeString& formatName, UErrorCode& status); /** * Sets one subformat for given format name. * See the class description about format name. * This function supports both named and numbered * arguments-- if numbered, the formatName is the * corresponding UnicodeStrings (e.g. "0", "1", "2"...). * If there is no matched formatName or wrong type, * the item will be ignored. * @param formatName Name of the subformat. * @param format the format to be set. * @param status output param set to success/failure code. * @stable ICU 4.0 */ virtual void setFormat(const UnicodeString& formatName, const Format& format, UErrorCode& status); /** * Sets one subformat for given format name. * See the class description about format name. * This function supports both named and numbered * arguments-- if numbered, the formatName is the * corresponding UnicodeStrings (e.g. "0", "1", "2"...). * If there is no matched formatName or wrong type, * the item will be ignored. * The caller should not delete the Format object after this call. * @param formatName Name of the subformat. * @param formatToAdopt Format to be adopted. * @param status output param set to success/failure code. * @stable ICU 4.0 */ virtual void adoptFormat(const UnicodeString& formatName, Format* formatToAdopt, UErrorCode& status); /** * Gets an array of subformats of this object. The returned array * should not be deleted by the caller, nor should the pointers * within the array. The array and its contents remain valid only * until the next call to this format. See the class description * about format numbering. * * @param count output parameter to receive the size of the array * @return an array of count Format* objects, or NULL if out of * memory. Any or all of the array elements may be NULL. * @stable ICU 2.0 */ virtual const Format** getFormats(int32_t& count) const; using Format::format; /** * Formats the given array of arguments into a user-readable string. * Does not take ownership of the Formattable* array or its contents. * * <p>If this format uses named arguments, appendTo is unchanged and * status is set to U_ILLEGAL_ARGUMENT_ERROR. * * @param source An array of objects to be formatted. * @param count The number of elements of 'source'. * @param appendTo Output parameter to receive result. * Result is appended to existing contents. * @param ignore Not used; inherited from base class API. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @return Reference to 'appendTo' parameter. * @stable ICU 2.0 */ UnicodeString& format(const Formattable* source, int32_t count, UnicodeString& appendTo, FieldPosition& ignore, UErrorCode& status) const; /** * Formats the given array of arguments into a user-readable string * using the given pattern. * * <p>If this format uses named arguments, appendTo is unchanged and * status is set to U_ILLEGAL_ARGUMENT_ERROR. * * @param pattern The pattern. * @param arguments An array of objects to be formatted. * @param count The number of elements of 'source'. * @param appendTo Output parameter to receive result. * Result is appended to existing contents. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @return Reference to 'appendTo' parameter. * @stable ICU 2.0 */ static UnicodeString& format(const UnicodeString& pattern, const Formattable* arguments, int32_t count, UnicodeString& appendTo, UErrorCode& status); /** * Formats the given array of arguments into a user-readable * string. The array must be stored within a single Formattable * object of type kArray. If the Formattable object type is not of * type kArray, then returns a failing UErrorCode. * * <p>If this format uses named arguments, appendTo is unchanged and * status is set to U_ILLEGAL_ARGUMENT_ERROR. * * @param obj A Formattable of type kArray containing * arguments to be formatted. * @param appendTo Output parameter to receive result. * Result is appended to existing contents. * @param pos On input: an alignment field, if desired. * On output: the offsets of the alignment field. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @return Reference to 'appendTo' parameter. * @stable ICU 2.0 */ virtual UnicodeString& format(const Formattable& obj, UnicodeString& appendTo, FieldPosition& pos, UErrorCode& status) const; /** * Formats the given array of arguments into a user-defined argument name * array. This function supports both named and numbered * arguments-- if numbered, the formatName is the * corresponding UnicodeStrings (e.g. "0", "1", "2"...). * * @param argumentNames argument name array * @param arguments An array of objects to be formatted. * @param count The number of elements of 'argumentNames' and * arguments. The number of argumentNames and arguments * must be the same. * @param appendTo Output parameter to receive result. * Result is appended to existing contents. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @return Reference to 'appendTo' parameter. * @stable ICU 4.0 */ UnicodeString& format(const UnicodeString* argumentNames, const Formattable* arguments, int32_t count, UnicodeString& appendTo, UErrorCode& status) const; /** * Parses the given string into an array of output arguments. * * @param source String to be parsed. * @param pos On input, starting position for parse. On output, * final position after parse. Unchanged if parse * fails. * @param count Output parameter to receive the number of arguments * parsed. * @return an array of parsed arguments. The caller owns both * the array and its contents. * @stable ICU 2.0 */ virtual Formattable* parse(const UnicodeString& source, ParsePosition& pos, int32_t& count) const; /** * Parses the given string into an array of output arguments. * * <p>If this format uses named arguments, status is set to * U_ARGUMENT_TYPE_MISMATCH. * * @param source String to be parsed. * @param count Output param to receive size of returned array. * @param status Input/output error code. If the * pattern cannot be parsed, set to failure code. * @return an array of parsed arguments. The caller owns both * the array and its contents. Returns NULL if status is not U_ZERO_ERROR. * * @stable ICU 2.0 */ virtual Formattable* parse(const UnicodeString& source, int32_t& count, UErrorCode& status) const; /** * Parses the given string into an array of output arguments * stored within a single Formattable of type kArray. * * @param source The string to be parsed into an object. * @param result Formattable to be set to the parse result. * If parse fails, return contents are undefined. * @param pos On input, starting position for parse. On output, * final position after parse. Unchanged if parse * fails. * @stable ICU 2.0 */ virtual void parseObject(const UnicodeString& source, Formattable& result, ParsePosition& pos) const; /** * Convert an 'apostrophe-friendly' pattern into a standard * pattern. Standard patterns treat all 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. * * <p><b>Note</b> 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. * * @param pattern the 'apostrophe-friendly' patttern to convert * @param status Input/output error code. If the pattern * cannot be parsed, the failure code is set. * @return the standard equivalent of the original pattern * @stable ICU 3.4 */ static UnicodeString autoQuoteApostrophe(const UnicodeString& pattern, UErrorCode& status); /** * Returns true if this MessageFormat uses named arguments, * and false otherwise. See class description. * * @return true if named arguments are used. * @stable ICU 4.0 */ UBool usesNamedArguments() const; #ifndef U_HIDE_INTERNAL_API /** * This API is for ICU internal use only. * Please do not use it. * * Returns argument types count in the parsed pattern. * Used to distinguish pattern "{0} d" and "d". * * @return The number of formattable types in the pattern * @internal */ int32_t getArgTypeCount() const; #endif /* U_HIDE_INTERNAL_API */ /** * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. * This method is to implement a simple version of RTTI, since not all * C++ compilers support genuine RTTI. Polymorphic operator==() and * clone() methods call this method. * * @return The class ID for this object. All objects of a * given class have the same class ID. Objects of * other classes have different class IDs. * @stable ICU 2.0 */ virtual UClassID getDynamicClassID(void) const; /** * Return the class ID for this class. This is useful only for * comparing to a return value from getDynamicClassID(). For example: * <pre> * . Base* polymorphic_pointer = createPolymorphicObject(); * . if (polymorphic_pointer->getDynamicClassID() == * . Derived::getStaticClassID()) ... * </pre> * @return The class ID for all objects of this class. * @stable ICU 2.0 */ static UClassID U_EXPORT2 getStaticClassID(void); #ifndef U_HIDE_INTERNAL_API /** * Compares two Format objects. This is used for constructing the hash * tables. * * @param left pointer to a Format object. Must not be NULL. * @param right pointer to a Format object. Must not be NULL. * * @return whether the two objects are the same * @internal */ static UBool equalFormats(const void* left, const void* right); #endif /* U_HIDE_INTERNAL_API */ private: Locale fLocale; MessagePattern msgPattern; Format** formatAliases; // see getFormats int32_t formatAliasesCapacity; MessageFormat(); // default constructor not implemented /** * This provider helps defer instantiation of a PluralRules object * until we actually need to select a keyword. * For example, if the number matches an explicit-value selector like "=1" * we do not need any PluralRules. */ class U_I18N_API PluralSelectorProvider : public PluralFormat::PluralSelector { public: PluralSelectorProvider(const MessageFormat &mf, UPluralType type); virtual ~PluralSelectorProvider(); virtual UnicodeString select(void *ctx, double number, UErrorCode& ec) const; void reset(); private: const MessageFormat &msgFormat; PluralRules* rules; UPluralType type; }; /** * A MessageFormat formats an array of arguments. Each argument * has an expected type, based on the pattern. For example, if * the pattern contains the subformat "{3,number,integer}", then * we expect argument 3 to have type Formattable::kLong. This * array needs to grow dynamically if the MessageFormat is * modified. */ Formattable::Type* argTypes; int32_t argTypeCount; int32_t argTypeCapacity; /** * TRUE if there are different argTypes for the same argument. * This only matters when the MessageFormat is used in the plain C (umsg_xxx) API * where the pattern argTypes determine how the va_arg list is read. */ UBool hasArgTypeConflicts; // Variable-size array management UBool allocateArgTypes(int32_t capacity, UErrorCode& status); /** * Default Format objects used when no format is specified and a * numeric or date argument is formatted. These are volatile * cache objects maintained only for performance. They do not * participate in operator=(), copy constructor(), nor * operator==(). */ NumberFormat* defaultNumberFormat; DateFormat* defaultDateFormat; UHashtable* cachedFormatters; UHashtable* customFormatArgStarts; PluralSelectorProvider pluralProvider; PluralSelectorProvider ordinalProvider; /** * Method to retrieve default formats (or NULL on failure). * These are semantically const, but may modify *this. */ const NumberFormat* getDefaultNumberFormat(UErrorCode&) const; const DateFormat* getDefaultDateFormat(UErrorCode&) const; /** * Finds the word s, in the keyword list and returns the located index. * @param s the keyword to be searched for. * @param list the list of keywords to be searched with. * @return the index of the list which matches the keyword s. */ static int32_t findKeyword( const UnicodeString& s, const char16_t * const *list); /** * Thin wrapper around the format(... AppendableWrapper ...) variant. * Wraps the destination UnicodeString into an AppendableWrapper and * supplies default values for some other parameters. */ UnicodeString& format(const Formattable* arguments, const UnicodeString *argumentNames, int32_t cnt, UnicodeString& appendTo, FieldPosition* pos, UErrorCode& status) const; /** * Formats the arguments and writes the result into the * AppendableWrapper, updates the field position. * * @param msgStart Index to msgPattern part to start formatting from. * @param plNumber NULL except when formatting a plural argument sub-message * where a '#' is replaced by the format string for this number. * @param arguments The formattable objects array. (Must not be NULL.) * @param argumentNames NULL if numbered values are used. Otherwise the same * length as "arguments", and each entry is the name of the * corresponding argument in "arguments". * @param cnt The length of arguments (and of argumentNames if that is not NULL). * @param appendTo Output parameter to receive the result. * The result string is appended to existing contents. * @param pos Field position status. * @param success The error code status. */ void format(int32_t msgStart, const void *plNumber, const Formattable* arguments, const UnicodeString *argumentNames, int32_t cnt, AppendableWrapper& appendTo, FieldPosition* pos, UErrorCode& success) const; UnicodeString getArgName(int32_t partIndex); void setArgStartFormat(int32_t argStart, Format* formatter, UErrorCode& status); void setCustomArgStartFormat(int32_t argStart, Format* formatter, UErrorCode& status); int32_t nextTopLevelArgStart(int32_t partIndex) const; UBool argNameMatches(int32_t partIndex, const UnicodeString& argName, int32_t argNumber); void cacheExplicitFormats(UErrorCode& status); int32_t skipLeadingSpaces(UnicodeString& style); Format* createAppropriateFormat(UnicodeString& type, UnicodeString& style, Formattable::Type& formattableType, UParseError& parseError, UErrorCode& ec); const Formattable* getArgFromListByName(const Formattable* arguments, const UnicodeString *argumentNames, int32_t cnt, UnicodeString& name) const; Formattable* parse(int32_t msgStart, const UnicodeString& source, ParsePosition& pos, int32_t& count, UErrorCode& ec) const; FieldPosition* updateMetaData(AppendableWrapper& dest, int32_t prevLength, FieldPosition* fp, const Formattable* argId) const; /** * Finds the "other" sub-message. * @param partIndex the index of the first PluralFormat argument style part. * @return the "other" sub-message start part index. */ int32_t findOtherSubMessage(int32_t partIndex) const; /** * 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. */ int32_t findFirstPluralNumberArg(int32_t msgStart, const UnicodeString &argName) const; Format* getCachedFormatter(int32_t argumentNumber) const; UnicodeString getLiteralStringUntilNextArgument(int32_t from) const; void copyObjects(const MessageFormat& that, UErrorCode& ec); void formatComplexSubMessage(int32_t msgStart, const void *plNumber, const Formattable* arguments, const UnicodeString *argumentNames, int32_t cnt, AppendableWrapper& appendTo, UErrorCode& success) const; /** * Convenience method that ought to be in NumberFormat */ NumberFormat* createIntegerFormat(const Locale& locale, UErrorCode& status) const; /** * Returns array of argument types in the parsed pattern * for use in C API. Only for the use of umsg_vformat(). Not * for public consumption. * @param listCount Output parameter to receive the size of array * @return The array of formattable types in the pattern */ const Formattable::Type* getArgTypeList(int32_t& listCount) const { listCount = argTypeCount; return argTypes; } /** * Resets the internal MessagePattern, and other associated caches. */ void resetPattern(); /** * A DummyFormatter that we use solely to store a NULL value. UHash does * not support storing NULL values. */ class U_I18N_API DummyFormat : public Format { public: virtual UBool operator==(const Format&) const; virtual DummyFormat* clone() const; virtual UnicodeString& format(const Formattable& obj, UnicodeString& appendTo, UErrorCode& status) const; virtual UnicodeString& format(const Formattable&, UnicodeString& appendTo, FieldPosition&, UErrorCode& status) const; virtual UnicodeString& format(const Formattable& obj, UnicodeString& appendTo, FieldPositionIterator* posIter, UErrorCode& status) const; virtual void parseObject(const UnicodeString&, Formattable&, ParsePosition&) const; }; friend class MessageFormatAdapter; // getFormatTypeList() access }; U_NAMESPACE_END #endif /* #if !UCONFIG_NO_FORMATTING */ #endif /* U_SHOW_CPLUSPLUS_API */ #endif // _MSGFMT //eof