1/* 2 ****************************************************************************** 3 * Copyright (C) 1997-2013, International Business Machines 4 * Corporation and others. All Rights Reserved. 5 ****************************************************************************** 6 */ 7 8/** 9 * \file 10 * \brief C++ API: Collation Element Iterator. 11 */ 12 13/** 14* File coleitr.h 15* 16* 17* 18* Created by: Helena Shih 19* 20* Modification History: 21* 22* Date Name Description 23* 24* 8/18/97 helena Added internal API documentation. 25* 08/03/98 erm Synched with 1.2 version CollationElementIterator.java 26* 12/10/99 aliu Ported Thai collation support from Java. 27* 01/25/01 swquek Modified into a C++ wrapper calling C APIs (ucoliter.h) 28* 02/19/01 swquek Removed CollationElementsIterator() since it is 29* private constructor and no calls are made to it 30*/ 31 32#ifndef COLEITR_H 33#define COLEITR_H 34 35#include "unicode/utypes.h" 36 37 38#if !UCONFIG_NO_COLLATION 39 40#include "unicode/uobject.h" 41#include "unicode/tblcoll.h" 42#include "unicode/ucoleitr.h" 43 44/** 45 * The UCollationElements struct. 46 * For usage in C programs. 47 * @stable ICU 2.0 48 */ 49typedef struct UCollationElements UCollationElements; 50 51U_NAMESPACE_BEGIN 52 53/** 54* The CollationElementIterator class is used as an iterator to walk through 55* each character of an international string. Use the iterator to return the 56* ordering priority of the positioned character. The ordering priority of a 57* character, which we refer to as a key, defines how a character is collated in 58* the given collation object. 59* For example, consider the following in Spanish: 60* <pre> 61* "ca" -> the first key is key('c') and second key is key('a'). 62* "cha" -> the first key is key('ch') and second key is key('a').</pre> 63* And in German, 64* <pre> \htmlonly "æb"-> the first key is key('a'), the second key is key('e'), and 65* the third key is key('b'). \endhtmlonly </pre> 66* The key of a character, is an integer composed of primary order(short), 67* secondary order(char), and tertiary order(char). Java strictly defines the 68* size and signedness of its primitive data types. Therefore, the static 69* functions primaryOrder(), secondaryOrder(), and tertiaryOrder() return 70* int32_t to ensure the correctness of the key value. 71* <p>Example of the iterator usage: (without error checking) 72* <pre> 73* \code 74* void CollationElementIterator_Example() 75* { 76* UnicodeString str = "This is a test"; 77* UErrorCode success = U_ZERO_ERROR; 78* RuleBasedCollator* rbc = 79* (RuleBasedCollator*) RuleBasedCollator::createInstance(success); 80* CollationElementIterator* c = 81* rbc->createCollationElementIterator( str ); 82* int32_t order = c->next(success); 83* c->reset(); 84* order = c->previous(success); 85* delete c; 86* delete rbc; 87* } 88* \endcode 89* </pre> 90* <p> 91* The method next() returns the collation order of the next character based on 92* the comparison level of the collator. The method previous() returns the 93* collation order of the previous character based on the comparison level of 94* the collator. The Collation Element Iterator moves only in one direction 95* between calls to reset(), setOffset(), or setText(). That is, next() 96* and previous() can not be inter-used. Whenever previous() is to be called after 97* next() or vice versa, reset(), setOffset() or setText() has to be called first 98* to reset the status, shifting pointers to either the end or the start of 99* the string (reset() or setText()), or the specified position (setOffset()). 100* Hence at the next call of next() or previous(), the first or last collation order, 101* or collation order at the spefcifieid position will be returned. If a change of 102* direction is done without one of these calls, the result is undefined. 103* <p> 104* The result of a forward iterate (next()) and reversed result of the backward 105* iterate (previous()) on the same string are equivalent, if collation orders 106* with the value UCOL_IGNORABLE are ignored. 107* Character based on the comparison level of the collator. A collation order 108* consists of primary order, secondary order and tertiary order. The data 109* type of the collation order is <strong>t_int32</strong>. 110* 111* Note, CollationElementIterator should not be subclassed. 112* @see Collator 113* @see RuleBasedCollator 114* @version 1.8 Jan 16 2001 115*/ 116class U_I18N_API CollationElementIterator : public UObject { 117public: 118 119 // CollationElementIterator public data member ------------------------------ 120 121 enum { 122 /** 123 * NULLORDER indicates that an error has occured while processing 124 * @stable ICU 2.0 125 */ 126 NULLORDER = (int32_t)0xffffffff 127 }; 128 129 // CollationElementIterator public constructor/destructor ------------------- 130 131 /** 132 * Copy constructor. 133 * 134 * @param other the object to be copied from 135 * @stable ICU 2.0 136 */ 137 CollationElementIterator(const CollationElementIterator& other); 138 139 /** 140 * Destructor 141 * @stable ICU 2.0 142 */ 143 virtual ~CollationElementIterator(); 144 145 // CollationElementIterator public methods ---------------------------------- 146 147 /** 148 * Returns true if "other" is the same as "this" 149 * 150 * @param other the object to be compared 151 * @return true if "other" is the same as "this" 152 * @stable ICU 2.0 153 */ 154 UBool operator==(const CollationElementIterator& other) const; 155 156 /** 157 * Returns true if "other" is not the same as "this". 158 * 159 * @param other the object to be compared 160 * @return true if "other" is not the same as "this" 161 * @stable ICU 2.0 162 */ 163 UBool operator!=(const CollationElementIterator& other) const; 164 165 /** 166 * Resets the cursor to the beginning of the string. 167 * @stable ICU 2.0 168 */ 169 void reset(void); 170 171 /** 172 * Gets the ordering priority of the next character in the string. 173 * @param status the error code status. 174 * @return the next character's ordering. otherwise returns NULLORDER if an 175 * error has occured or if the end of string has been reached 176 * @stable ICU 2.0 177 */ 178 int32_t next(UErrorCode& status); 179 180 /** 181 * Get the ordering priority of the previous collation element in the string. 182 * @param status the error code status. 183 * @return the previous element's ordering. otherwise returns NULLORDER if an 184 * error has occured or if the start of string has been reached 185 * @stable ICU 2.0 186 */ 187 int32_t previous(UErrorCode& status); 188 189 /** 190 * Gets the primary order of a collation order. 191 * @param order the collation order 192 * @return the primary order of a collation order. 193 * @stable ICU 2.0 194 */ 195 static inline int32_t primaryOrder(int32_t order); 196 197 /** 198 * Gets the secondary order of a collation order. 199 * @param order the collation order 200 * @return the secondary order of a collation order. 201 * @stable ICU 2.0 202 */ 203 static inline int32_t secondaryOrder(int32_t order); 204 205 /** 206 * Gets the tertiary order of a collation order. 207 * @param order the collation order 208 * @return the tertiary order of a collation order. 209 * @stable ICU 2.0 210 */ 211 static inline int32_t tertiaryOrder(int32_t order); 212 213 /** 214 * Return the maximum length of any expansion sequences that end with the 215 * specified comparison order. 216 * @param order a collation order returned by previous or next. 217 * @return maximum size of the expansion sequences ending with the collation 218 * element or 1 if collation element does not occur at the end of any 219 * expansion sequence 220 * @stable ICU 2.0 221 */ 222 int32_t getMaxExpansion(int32_t order) const; 223 224 /** 225 * Gets the comparison order in the desired strength. Ignore the other 226 * differences. 227 * @param order The order value 228 * @stable ICU 2.0 229 */ 230 int32_t strengthOrder(int32_t order) const; 231 232 /** 233 * Sets the source string. 234 * @param str the source string. 235 * @param status the error code status. 236 * @stable ICU 2.0 237 */ 238 void setText(const UnicodeString& str, UErrorCode& status); 239 240 /** 241 * Sets the source string. 242 * @param str the source character iterator. 243 * @param status the error code status. 244 * @stable ICU 2.0 245 */ 246 void setText(CharacterIterator& str, UErrorCode& status); 247 248 /** 249 * Checks if a comparison order is ignorable. 250 * @param order the collation order. 251 * @return TRUE if a character is ignorable, FALSE otherwise. 252 * @stable ICU 2.0 253 */ 254 static inline UBool isIgnorable(int32_t order); 255 256 /** 257 * Gets the offset of the currently processed character in the source string. 258 * @return the offset of the character. 259 * @stable ICU 2.0 260 */ 261 int32_t getOffset(void) const; 262 263 /** 264 * Sets the offset of the currently processed character in the source string. 265 * @param newOffset the new offset. 266 * @param status the error code status. 267 * @return the offset of the character. 268 * @stable ICU 2.0 269 */ 270 void setOffset(int32_t newOffset, UErrorCode& status); 271 272 /** 273 * ICU "poor man's RTTI", returns a UClassID for the actual class. 274 * 275 * @stable ICU 2.2 276 */ 277 virtual UClassID getDynamicClassID() const; 278 279 /** 280 * ICU "poor man's RTTI", returns a UClassID for this class. 281 * 282 * @stable ICU 2.2 283 */ 284 static UClassID U_EXPORT2 getStaticClassID(); 285 286private: 287 friend class RuleBasedCollator; 288 289 /** 290 * CollationElementIterator constructor. This takes the source string and the 291 * collation object. The cursor will walk thru the source string based on the 292 * predefined collation rules. If the source string is empty, NULLORDER will 293 * be returned on the calls to next(). 294 * @param sourceText the source string. 295 * @param order the collation object. 296 * @param status the error code status. 297 */ 298 CollationElementIterator(const UnicodeString& sourceText, 299 const RuleBasedCollator* order, UErrorCode& status); 300 301 /** 302 * CollationElementIterator constructor. This takes the source string and the 303 * collation object. The cursor will walk thru the source string based on the 304 * predefined collation rules. If the source string is empty, NULLORDER will 305 * be returned on the calls to next(). 306 * @param sourceText the source string. 307 * @param order the collation object. 308 * @param status the error code status. 309 */ 310 CollationElementIterator(const CharacterIterator& sourceText, 311 const RuleBasedCollator* order, UErrorCode& status); 312 313 /** 314 * Assignment operator 315 * 316 * @param other the object to be copied 317 */ 318 const CollationElementIterator& 319 operator=(const CollationElementIterator& other); 320 321 CollationElementIterator(); // default constructor not implemented 322 323 // CollationElementIterator private data members ---------------------------- 324 325 /** 326 * Data wrapper for collation elements 327 */ 328 UCollationElements *m_data_; 329 330 /** 331 * Indicates if m_data_ belongs to this object. 332 */ 333 UBool isDataOwned_; 334}; 335 336// CollationElementIterator inline method defination -------------------------- 337 338/** 339* Get the primary order of a collation order. 340* @param order the collation order 341* @return the primary order of a collation order. 342*/ 343inline int32_t CollationElementIterator::primaryOrder(int32_t order) 344{ 345 order &= RuleBasedCollator::PRIMARYORDERMASK; 346 return (order >> RuleBasedCollator::PRIMARYORDERSHIFT); 347} 348 349/** 350* Get the secondary order of a collation order. 351* @param order the collation order 352* @return the secondary order of a collation order. 353*/ 354inline int32_t CollationElementIterator::secondaryOrder(int32_t order) 355{ 356 order = order & RuleBasedCollator::SECONDARYORDERMASK; 357 return (order >> RuleBasedCollator::SECONDARYORDERSHIFT); 358} 359 360/** 361* Get the tertiary order of a collation order. 362* @param order the collation order 363* @return the tertiary order of a collation order. 364*/ 365inline int32_t CollationElementIterator::tertiaryOrder(int32_t order) 366{ 367 return (order &= RuleBasedCollator::TERTIARYORDERMASK); 368} 369 370inline int32_t CollationElementIterator::getMaxExpansion(int32_t order) const 371{ 372 return ucol_getMaxExpansion(m_data_, (uint32_t)order); 373} 374 375inline UBool CollationElementIterator::isIgnorable(int32_t order) 376{ 377 return (primaryOrder(order) == RuleBasedCollator::PRIMIGNORABLE); 378} 379 380U_NAMESPACE_END 381 382#endif /* #if !UCONFIG_NO_COLLATION */ 383 384#endif 385