/* * Copyright © {1997-1999}, 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) ******************************************************************************** */ // ***************************************************************************** // This file was generated from the java source file MessageFormat.java // ***************************************************************************** #ifndef MSGFMT_H #define MSGFMT_H #include "unicode/utypes.h" #include "unicode/format.h" #include "unicode/locid.h" class NumberFormat; /** * Provides means to produce concatenated messages in language-neutral way. * Use this for all concatenations that show up to end users. *

* Takes a set of objects, formats them, then inserts the formatted * strings into the pattern at the appropriate places. *

* Here are some examples of usage: * Example 1: *

 * \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} on {1,date}, there was {2} on planet {0,number}.",
 *          arguments, 3, result, success );
 *     
 *     cout << "result: " << result << endl;
 *     //<output>: At 4:34:20 PM on 23-Mar-98, there was a disturbance
 *     //             in the Force on planet 7.
 * \endcode
 * 
* Typically, the message format will come from resources, and the * arguments will be dynamically set at runtime. *

* Example 2: *

 *  \code
 *     success = U_ZERO_ERROR;
 *     Formattable testArgs[] = {3L, "MyDisk"};
 *    
 *     MessageFormat* form = new MessageFormat(
 *         "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).
 *     delete form;
 *  \endcode
 *  
* * The pattern is of the following form. Legend: *
 * \code
 *       {optional item}
 *       (group that may be repeated)*
 * \endcode
 *  
* Do not confuse optional items with items inside quotes braces, such * as this: "{". Quoted braces are literals. *
 *  \code
 *       messageFormatPattern := string ( "{" messageFormatElement "}" string )*
 *        
 *       messageFormatElement := argument { "," elementFormat }
 *        
 *       elementFormat := "time" { "," datetimeStyle }
 *                      | "date" { "," datetimeStyle }
 *                      | "number" { "," numberStyle }
 *                      | "choice" "," choiceStyle
 *   
 *       datetimeStyle := "short"
 *                      | "medium"
 *                      | "long"
 *                      | "full"
 *                      | dateFormatPattern
 * 
 *       numberStyle :=   "currency"
 *                      | "percent"
 *                      | "integer"
 *                      | numberFormatPattern
 *  
 *       choiceStyle :=   choiceFormatPattern
 * \endcode
 * 
* If there is no elementFormat, then the argument must be a string, * which is substituted. If there is no dateTimeStyle or numberStyle, * then the default format is used (e.g. NumberFormat.getInstance(), * DateFormat.getDefaultTime() or DateFormat.getDefaultDate(). For * a ChoiceFormat, the pattern must always be specified, since there * is no default. *

* In strings, single quotes can be used to quote the "{" sign if * necessary. A real single quote is represented by ''. Inside a * messageFormatElement, quotes are [not] removed. For example, * {1,number,$'#',##} will produce a number format with the pound-sign * quoted, with a result such as: "$#31,45". *

* If a pattern is used, then unquoted braces in the pattern, if any, * must match: that is, "ab {0} de" and "ab '}' de" are ok, but "ab * {0'}' de" and "ab } de" are not. *

* The argument is a number from 0 to 9, which corresponds to the * arguments presented in an array to be formatted. *

* It is ok to have unused arguments in the array. With missing * arguments or arguments that are not of the right class for the * specified format, a failing UErrorCode result is set. *

* For more sophisticated patterns, you can use a ChoiceFormat to get * output such as: *

 * \code
 *     UErrorCode success = U_ZERO_ERROR;
 *     MessageFormat* form = new MessageFormat("The disk \"{1}\" contains {0}.", success);
 *     double filelimits[] = {0,1,2};
 *     UnicodeString filepart[] = {"no files","one file","{0,number} files"};
 *     ChoiceFormat* fileform = new ChoiceFormat(filelimits, filepart, 3);
 *     form->setFormat(1, *fileform); // NOT zero, see below
 *     
 *     Formattable testArgs[] = {1273L, "MyDisk"};
 *      
 *     UnicodeString string;
 *     FieldPosition fpos = 0;
 *     cout << form->format(testArgs, 2, string, fpos, success) << endl;
 *     
 *     // output, with different testArgs
 *     // output: The disk "MyDisk" contains no files.
 *     // output: The disk "MyDisk" contains one file.
 *     // output: The disk "MyDisk" contains 1,273 files.
 * \endcode
 * 
* You can either do this programmatically, as in the above example, * or by using a pattern (see ChoiceFormat for more information) as in: *
 * \code
 *    form->applyPattern(
 *      "There {0,choice,0#are no files|1#is one file|1<are {0,number,integer} files}.");
 * \endcode
 * 
*

* [Note:] As we see above, the string produced by a ChoiceFormat in * MessageFormat is treated specially; occurances of '{' are used to * indicated subformats, and cause recursion. If you create both a * MessageFormat and ChoiceFormat programmatically (instead of using * the string patterns), then be careful not to produce a format that * recurses on itself, which will cause an infinite loop. *

* [Note:] Formats are numbered by order of variable in the string. * This is [not] the same as the argument numbering! *

 * \code
 *    For example: with "abc{2}def{3}ghi{0}...",
 *    
 *    format0 affects the first variable {2}
 *    format1 affects the second variable {3}
 *    format2 affects the second variable {0}
 * \endcode
 * 
* and so on. */ class U_I18N_API MessageFormat : public Format { public: enum EFormatNumber { kMaxFormat = 10 }; /** * Construct a new MessageFormat using the given pattern. * * @param pattern Pattern used to construct object. * @param status Output param to receive success code. If the * pattern cannot be parsed, set to failure code. * @stable */ MessageFormat(const UnicodeString& pattern, UErrorCode &status); /** * Constructor that allows locale specification. * @param pattern Pattern used to construct object. * @param newLocale The locale to use for formatting dates and numbers. * @param status Output param to receive success code. If the * pattern cannot be parsed, set to failure code. * @stable */ MessageFormat(const UnicodeString& pattern, const Locale& newLocale, UErrorCode& success); /** * Copy constructor. * @stable */ MessageFormat(const MessageFormat&); /** * Assignment operator. * @stable */ const MessageFormat& operator=(const MessageFormat&); /** * Destructor. * @stable */ virtual ~MessageFormat(); /** * Clone this Format object polymorphically. The caller owns the * result and should delete it when done. * @stable */ virtual Format* clone(void) const; /** * Return true if the given Format objects are semantically equal. * Objects of different subclasses are considered unequal. * @stable */ virtual UBool operator==(const Format& other) const; /** * Sets the locale. This locale is used for fetching default number or date * format information. * @stable */ virtual void setLocale(const Locale& theLocale); /** * Gets the locale. This locale is used for fetching default number or date * format information. * @stable */ virtual const Locale& getLocale(void) const; /** * Apply the given pattern string to this message format. * * @param pattern The pattern to be applied. * @param status Output param set to success/failure code on * exit. If the pattern is invalid, this will be * set to a failure result. * @stable */ virtual void applyPattern(const UnicodeString& pattern, UErrorCode& status); /** * Gets the pattern. See the class description. * @stable */ virtual UnicodeString& toPattern(UnicodeString& result) const; /** * Sets formats to use on parameters. * See the class description about format numbering. * The caller should not delete the Format objects after this call. * @draft HSYS: possible semantic change on limitation of the size of array */ virtual void adoptFormats(Format** formatsToAdopt, int32_t count); /** * Sets formats to use on parameters. * See the class description about format numbering. * @draft HSYS: possible semantic change on limitation of the size of array */ virtual void setFormats(const Format** newFormats,int32_t cnt); /** * Sets formats individually to use on parameters. * See the class description about format numbering. * The caller should not delete the Format object after this call. * @draft HSYS: possible semantic change on limitation of the size of array */ virtual void adoptFormat(int32_t formatNumber, Format* formatToAdopt); /** * Sets formats individually to use on parameters. * See the class description about format numbering. * @stable */ virtual void setFormat(int32_t variable, const Format& newFormat); /** * Gets formats that were set with setFormats. * See the class description about format numbering. * @draft HSYS: possible semantic change on limitation of the size of array */ virtual const Format** getFormats(int32_t& count) const; /** * Returns pattern with formatted objects. Does not take ownership * of the Formattable* array; just reads it and uses it to generate * the format string. * * @param source An array of objects to be formatted & substituted. * @param result Where text is appended. * @param ignore No useful status is returned. * @stable */ UnicodeString& format( const Formattable* source, int32_t count, UnicodeString& result, FieldPosition& ignore, UErrorCode& success) const; /** * Convenience routine. Avoids explicit creation of * MessageFormat, but doesn't allow future optimizations. * @stable */ static UnicodeString& format( const UnicodeString& pattern, const Formattable* arguments, int32_t count, UnicodeString& result, UErrorCode& success); /** * Format an object to produce a message. This method handles * Formattable objects of type kArray. If the Formattable * object type is not of type kArray, then it returns a failing * UErrorCode. * * @param obj The object to format * @param toAppendTo Where the text is to be appended * @param pos On input: an alignment field, if desired. * On output: the offsets of the alignment field. * @param status Output param filled with success/failure status. * @return The value passed in as toAppendTo (this allows chaining, * as with UnicodeString::append()) * @stable */ virtual UnicodeString& format(const Formattable& obj, UnicodeString& toAppendTo, FieldPosition& pos, UErrorCode& status) const; /** * Redeclared Format method. * @stable */ UnicodeString& format(const Formattable& obj, UnicodeString& result, UErrorCode& status) const; /** * 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 is 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 formatted twice in the string, then the * later parse wins. * * @param source String to be parsed. * @param status On input, starting position for parse. On output, * final position after parse. * @param count Output param to receive size of returned array. * @result Array of Formattable objects, with length * 'count', owned by the caller. * @stable */ virtual Formattable* parse( const UnicodeString& source, ParsePosition& status, int32_t& count) const; /** * Parses the string. Does not yet handle recursion (where * the substituted strings contain {n} references.) * * @param source String to be parsed. * @param count Output param to receive size of returned array. * @param status Output param to receive success/error code. * @result Array of Formattable objects, with length * 'count', owned by the caller. * @stable */ virtual Formattable* parse( const UnicodeString& source, int32_t& count, UErrorCode& status) const; /** * Parse a string to produce an object. This methods handles * parsing of message strings into arrays of Formattable objects. * Does not yet handle recursion (where the substituted strings * contain %n references.) *

* Before calling, set parse_pos.index to the offset you want to * start parsing at in the source. After calling, parse_pos.index * is the end of the text you parsed. If error occurs, index is * unchanged. *

* When parsing, leading whitespace is discarded (with successful * parse), while trailing whitespace is left as is. *

* See Format::parseObject() for more. * * @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 parse_pos The position to start parsing at. Upon return * this param is set to the position after the * last character successfully parsed. If the * source is not parsed successfully, this param * will remain unchanged. * @return A newly created Formattable* object, or NULL * on failure. The caller owns this and should * delete it when done. * @stable */ virtual void parseObject(const UnicodeString& source, Formattable& result, ParsePosition& parse_pos) const; public: /** * 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 */ 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: *

     * .   Base* polymorphic_pointer = createPolymorphicObject();
     * .   if (polymorphic_pointer->getDynamicClassID() ==
     * .      Derived::getStaticClassID()) ...
     * 
* @return The class ID for all objects of this class. * @stable */ static UClassID getStaticClassID(void) { return (UClassID)&fgClassID; } private: static char fgClassID; static NumberFormat* fgNumberFormat; // fgNumberFormat is held in a cache of one. static NumberFormat* getNumberFormat(UErrorCode &status); // call this function to 'check out' a numberformat from the cache. static void releaseNumberFormat(NumberFormat *adopt); // call this function to 'return' the number format to the cache. Locale fLocale; UnicodeString fPattern; // later, allow more than ten items Format *fFormats[kMaxFormat]; int32_t *fOffsets; int32_t fCount; int32_t *fArgumentNumbers; int32_t fMaxOffset; /** * Internal routine used by format. * @param recursionProtection Initially zero. Bits 0..9 are used to indicate * that a parameter has already been seen, to avoid recursion. Currently * unused. */ static const int32_t fgListLength; static const UnicodeString fgTypeList[]; static const UnicodeString fgModifierList[]; static const UnicodeString fgDateModifierList[]; /** * 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 UnicodeString* list); /** * Formats the array of arguments and copies the result into the result buffer, * updates the field position. * @param arguments the formattable objects array. * @param cnt the array count. * @param status field position status. * @param recursionProtection Initially zero. Bits 0..9 are used to indicate * that a parameter has already been seen, to avoid recursion. Currently * unused. * @param success the error code status. */ UnicodeString& format( const Formattable* arguments, int32_t cnt, UnicodeString& result, FieldPosition& status, int32_t recursionProtection, UErrorCode& success) const; /** * Checks the segments for the closest matched format instance and * updates the format array with the new format instance. * @param position the last processed offset in the pattern * @param offsetNumber the offset number of the last processed segment * @param segments the string that contains the parsed pattern segments. * @param success the error code */ void makeFormat( /*int32_t position, */ int32_t offsetNumber, UnicodeString* segments, UErrorCode& success); /** * Convenience method that ought to be in NumberFormat */ NumberFormat* createIntegerFormat(const Locale& locale, UErrorCode& status) const; /** * Checks the range of the source text to quote the special * characters, { and ' and copy to target buffer. * @param source * @param start the text offset to start the process of in the source string * @param end the text offset to end the process of in the source string * @param target the result buffer */ static void copyAndFixQuotes(const UnicodeString& source, int32_t start, int32_t end, UnicodeString& target); /** * Converts a string to an integer value using a default NumberFormat object * which is static (shared by all MessageFormat instances). This replaces * a call to wtoi(). * @param string the source string to convert with * @param status the error code. * @return the converted number. */ static int32_t stoi(const UnicodeString& string, UErrorCode& status); /** * Converts an integer value to a string using a default NumberFormat object * which is static (shared by all MessageFormat instances). This replaces * a call to wtoi(). * @param i the integer to format * @param string the destination string * @return a reference to string. */ static UnicodeString& itos(int32_t i, UnicodeString& string); }; inline UClassID MessageFormat::getDynamicClassID() const { return MessageFormat::getStaticClassID(); } inline UnicodeString& MessageFormat::format(const Formattable& obj, UnicodeString& result, UErrorCode& status) const { return Format::format(obj, result, status); } #endif // _MSGFMT //eof