* For more information about the collation service see * the User Guide. *
* Collation service provides correct sorting orders for most locales supported in ICU. * If specific data for a locale is not available, the orders eventually falls back * to the CLDR root sort order. *
* Sort ordering may be customized by providing your own set of rules. For more on * this subject see the * Collation Customization section of the User Guide. *
* Note, RuleBasedCollator is not to be subclassed. * @see Collator */ class U_I18N_API RuleBasedCollator : public Collator { public: /** * RuleBasedCollator constructor. This takes the table rules and builds a * collation table out of them. Please see RuleBasedCollator class * description for more details on the collation rule syntax. * @param rules the collation rules to build the collation table from. * @param status reporting a success or an error. * @stable ICU 2.0 */ RuleBasedCollator(const UnicodeString& rules, UErrorCode& status); /** * RuleBasedCollator constructor. This takes the table rules and builds a * collation table out of them. Please see RuleBasedCollator class * description for more details on the collation rule syntax. * @param rules the collation rules to build the collation table from. * @param collationStrength strength for comparison * @param status reporting a success or an error. * @stable ICU 2.0 */ RuleBasedCollator(const UnicodeString& rules, ECollationStrength collationStrength, UErrorCode& status); /** * RuleBasedCollator constructor. This takes the table rules and builds a * collation table out of them. Please see RuleBasedCollator class * description for more details on the collation rule syntax. * @param rules the collation rules to build the collation table from. * @param decompositionMode the normalisation mode * @param status reporting a success or an error. * @stable ICU 2.0 */ RuleBasedCollator(const UnicodeString& rules, UColAttributeValue decompositionMode, UErrorCode& status); /** * RuleBasedCollator constructor. This takes the table rules and builds a * collation table out of them. Please see RuleBasedCollator class * description for more details on the collation rule syntax. * @param rules the collation rules to build the collation table from. * @param collationStrength strength for comparison * @param decompositionMode the normalisation mode * @param status reporting a success or an error. * @stable ICU 2.0 */ RuleBasedCollator(const UnicodeString& rules, ECollationStrength collationStrength, UColAttributeValue decompositionMode, UErrorCode& status); #ifndef U_HIDE_INTERNAL_API /** * TODO: document & propose as public API * @internal */ RuleBasedCollator(const UnicodeString &rules, UParseError &parseError, UnicodeString &reason, UErrorCode &errorCode); #endif /* U_HIDE_INTERNAL_API */ /** * Copy constructor. * @param other the RuleBasedCollator object to be copied * @stable ICU 2.0 */ RuleBasedCollator(const RuleBasedCollator& other); /** Opens a collator from a collator binary image created using * cloneBinary. Binary image used in instantiation of the * collator remains owned by the user and should stay around for * the lifetime of the collator. The API also takes a base collator * which must be the root collator. * @param bin binary image owned by the user and required through the * lifetime of the collator * @param length size of the image. If negative, the API will try to * figure out the length of the image * @param base Base collator, for lookup of untailored characters. * Must be the root collator, must not be NULL. * The base is required to be present through the lifetime of the collator. * @param status for catching errors * @return newly created collator * @see cloneBinary * @stable ICU 3.4 */ RuleBasedCollator(const uint8_t *bin, int32_t length, const RuleBasedCollator *base, UErrorCode &status); /** * Destructor. * @stable ICU 2.0 */ virtual ~RuleBasedCollator(); /** * Assignment operator. * @param other other RuleBasedCollator object to copy from. * @stable ICU 2.0 */ RuleBasedCollator& operator=(const RuleBasedCollator& other); /** * Returns true if argument is the same as this object. * @param other Collator object to be compared. * @return true if arguments is the same as this object. * @stable ICU 2.0 */ virtual UBool operator==(const Collator& other) const; /** * Makes a copy of this object. * @return a copy of this object, owned by the caller * @stable ICU 2.0 */ virtual RuleBasedCollator* clone() const; /** * Creates a collation element iterator for the source string. The caller of * this method is responsible for the memory management of the return * pointer. * @param source the string over which the CollationElementIterator will * iterate. * @return the collation element iterator of the source string using this as * the based Collator. * @stable ICU 2.2 */ virtual CollationElementIterator* createCollationElementIterator( const UnicodeString& source) const; /** * Creates a collation element iterator for the source. The caller of this * method is responsible for the memory management of the returned pointer. * @param source the CharacterIterator which produces the characters over * which the CollationElementItgerator will iterate. * @return the collation element iterator of the source using this as the * based Collator. * @stable ICU 2.2 */ virtual CollationElementIterator* createCollationElementIterator( const CharacterIterator& source) const; // Make deprecated versions of Collator::compare() visible. using Collator::compare; /** * The comparison function compares the character data stored in two * different strings. Returns information about whether a string is less * than, greater than or equal to another string. * @param source the source string to be compared with. * @param target the string that is to be compared with the source string. * @param status possible error code * @return Returns an enum value. UCOL_GREATER if source is greater * than target; UCOL_EQUAL if source is equal to target; UCOL_LESS if source is less * than target * @stable ICU 2.6 **/ virtual UCollationResult compare(const UnicodeString& source, const UnicodeString& target, UErrorCode &status) const; /** * Does the same thing as compare but limits the comparison to a specified * length * @param source the source string to be compared with. * @param target the string that is to be compared with the source string. * @param length the length the comparison is limited to * @param status possible error code * @return Returns an enum value. UCOL_GREATER if source (up to the specified * length) is greater than target; UCOL_EQUAL if source (up to specified * length) is equal to target; UCOL_LESS if source (up to the specified * length) is less than target. * @stable ICU 2.6 */ virtual UCollationResult compare(const UnicodeString& source, const UnicodeString& target, int32_t length, UErrorCode &status) const; /** * The comparison function compares the character data stored in two * different string arrays. Returns information about whether a string array * is less than, greater than or equal to another string array. * @param source the source string array to be compared with. * @param sourceLength the length of the source string array. If this value * is equal to -1, the string array is null-terminated. * @param target the string that is to be compared with the source string. * @param targetLength the length of the target string array. If this value * is equal to -1, the string array is null-terminated. * @param status possible error code * @return Returns an enum value. UCOL_GREATER if source is greater * than target; UCOL_EQUAL if source is equal to target; UCOL_LESS if source is less * than target * @stable ICU 2.6 */ virtual UCollationResult compare(const char16_t* source, int32_t sourceLength, const char16_t* target, int32_t targetLength, UErrorCode &status) const; /** * Compares two strings using the Collator. * Returns whether the first one compares less than/equal to/greater than * the second one. * This version takes UCharIterator input. * @param sIter the first ("source") string iterator * @param tIter the second ("target") string iterator * @param status ICU status * @return UCOL_LESS, UCOL_EQUAL or UCOL_GREATER * @stable ICU 4.2 */ virtual UCollationResult compare(UCharIterator &sIter, UCharIterator &tIter, UErrorCode &status) const; /** * Compares two UTF-8 strings using the Collator. * Returns whether the first one compares less than/equal to/greater than * the second one. * This version takes UTF-8 input. * Note that a StringPiece can be implicitly constructed * from a std::string or a NUL-terminated const char * string. * @param source the first UTF-8 string * @param target the second UTF-8 string * @param status ICU status * @return UCOL_LESS, UCOL_EQUAL or UCOL_GREATER * @stable ICU 51 */ virtual UCollationResult compareUTF8(const StringPiece &source, const StringPiece &target, UErrorCode &status) const; /** * Transforms the string into a series of characters * that can be compared with CollationKey.compare(). * * Note that sort keys are often less efficient than simply doing comparison. * For more details, see the ICU User Guide. * * @param source the source string. * @param key the transformed key of the source string. * @param status the error code status. * @return the transformed key. * @see CollationKey * @stable ICU 2.0 */ virtual CollationKey& getCollationKey(const UnicodeString& source, CollationKey& key, UErrorCode& status) const; /** * Transforms a specified region of the string into a series of characters * that can be compared with CollationKey.compare. * * Note that sort keys are often less efficient than simply doing comparison. * For more details, see the ICU User Guide. * * @param source the source string. * @param sourceLength the length of the source string. * @param key the transformed key of the source string. * @param status the error code status. * @return the transformed key. * @see CollationKey * @stable ICU 2.0 */ virtual CollationKey& getCollationKey(const char16_t *source, int32_t sourceLength, CollationKey& key, UErrorCode& status) const; /** * Generates the hash code for the rule-based collation object. * @return the hash code. * @stable ICU 2.0 */ virtual int32_t hashCode() const; #ifndef U_FORCE_HIDE_DEPRECATED_API /** * Gets the locale of the Collator * @param type can be either requested, valid or actual locale. For more * information see the definition of ULocDataLocaleType in * uloc.h * @param status the error code status. * @return locale where the collation data lives. If the collator * was instantiated from rules, locale is empty. * @deprecated ICU 2.8 likely to change in ICU 3.0, based on feedback */ virtual Locale getLocale(ULocDataLocaleType type, UErrorCode& status) const; #endif // U_FORCE_HIDE_DEPRECATED_API /** * Gets the tailoring rules for this collator. * @return the collation tailoring from which this collator was created * @stable ICU 2.0 */ const UnicodeString& getRules() const; /** * Gets the version information for a Collator. * @param info the version # information, the result will be filled in * @stable ICU 2.0 */ virtual void getVersion(UVersionInfo info) const; #ifndef U_HIDE_DEPRECATED_API /** * Returns the maximum length of any expansion sequences that end with the * specified comparison order. * * This is specific to the kind of collation element values and sequences * returned by the CollationElementIterator. * Call CollationElementIterator::getMaxExpansion() instead. * * @param order a collation order returned by CollationElementIterator::previous * or CollationElementIterator::next. * @return maximum size of the expansion sequences ending with the collation * element, or 1 if the collation element does not occur at the end of * any expansion sequence * @see CollationElementIterator#getMaxExpansion * @deprecated ICU 51 Use CollationElementIterator::getMaxExpansion() instead. */ int32_t getMaxExpansion(int32_t order) const; #endif /* U_HIDE_DEPRECATED_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; /** * Returns 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()) ... *