summaryrefslogtreecommitdiff
path: root/Build/source/libs/icu/icu-4.4/i18n/unicode/coleitr.h
blob: 4025a41d730997c2f00e37475881abfda4fb6ec8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
/*
 ******************************************************************************
 *   Copyright (C) 1997-2008, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 ******************************************************************************
 */

/**
 * \file 
 * \brief C++ API: Collation Element Iterator.
 */

/**
* File coleitr.h
*
* 
*
* Created by: Helena Shih
*
* Modification History:
*
*  Date       Name        Description
*
*  8/18/97    helena      Added internal API documentation.
* 08/03/98    erm         Synched with 1.2 version CollationElementIterator.java
* 12/10/99    aliu        Ported Thai collation support from Java.
* 01/25/01    swquek      Modified into a C++ wrapper calling C APIs (ucoliter.h)
* 02/19/01    swquek      Removed CollationElementsIterator() since it is 
*                         private constructor and no calls are made to it
*/

#ifndef COLEITR_H
#define COLEITR_H

#include "unicode/utypes.h"

 
#if !UCONFIG_NO_COLLATION

#include "unicode/uobject.h"
#include "unicode/tblcoll.h"
#include "unicode/ucoleitr.h"

/** 
 * The UCollationElements struct.
 * For usage in C programs.
 * @stable ICU 2.0
 */
typedef struct UCollationElements UCollationElements;

U_NAMESPACE_BEGIN

/**
* The CollationElementIterator class is used as an iterator to walk through     
* each character of an international string. Use the iterator to return the
* ordering priority of the positioned character. The ordering priority of a 
* character, which we refer to as a key, defines how a character is collated in 
* the given collation object.
* For example, consider the following in Spanish:
* <pre>
*        "ca" -> the first key is key('c') and second key is key('a').
*        "cha" -> the first key is key('ch') and second key is key('a').</pre>
* And in German,
* <pre> \htmlonly       "&#x00E6;b"-> the first key is key('a'), the second key is key('e'), and
*        the third key is key('b'). \endhtmlonly </pre>
* The key of a character, is an integer composed of primary order(short),
* secondary order(char), and tertiary order(char). Java strictly defines the 
* size and signedness of its primitive data types. Therefore, the static
* functions primaryOrder(), secondaryOrder(), and tertiaryOrder() return 
* int32_t to ensure the correctness of the key value.
* <p>Example of the iterator usage: (without error checking)
* <pre>
* \code
*   void CollationElementIterator_Example()
*   {
*       UnicodeString str = "This is a test";
*       UErrorCode success = U_ZERO_ERROR;
*       RuleBasedCollator* rbc =
*           (RuleBasedCollator*) RuleBasedCollator::createInstance(success);
*       CollationElementIterator* c =
*           rbc->createCollationElementIterator( str );
*       int32_t order = c->next(success);
*       c->reset();
*       order = c->previous(success);
*       delete c;
*       delete rbc;
*   }
* \endcode
* </pre>
* <p>
* CollationElementIterator::next returns the collation order of the next
* character based on the comparison level of the collator. 
* CollationElementIterator::previous returns the collation order of the 
* previous character based on the comparison level of the collator. 
* The Collation Element Iterator moves only in one direction between calls to
* CollationElementIterator::reset. That is, CollationElementIterator::next() 
* and CollationElementIterator::previous can not be inter-used. Whenever 
* CollationElementIterator::previous is to be called after 
* CollationElementIterator::next() or vice versa, 
* CollationElementIterator::reset has to be called first to reset the status, 
* shifting pointers to either the end or the start of the string. Hence at the 
* next call of CollationElementIterator::previous or 
* CollationElementIterator::next(), the first or last collation order will be 
* returned. 
* If a change of direction is done without a CollationElementIterator::reset(), 
* the result is undefined.
* The result of a forward iterate (CollationElementIterator::next) and 
* reversed result of the backward iterate (CollationElementIterator::previous) 
* on the same string are equivalent, if collation orders with the value 
* UCOL_IGNORABLE are ignored.
* Character based on the comparison level of the collator.  A collation order 
* consists of primary order, secondary order and tertiary order.  The data 
* type of the collation order is <strong>t_int32</strong>. 
*
* Note, CollationElementIterator should not be subclassed.
* @see     Collator
* @see     RuleBasedCollator
* @version 1.8 Jan 16 2001
*/
class U_I18N_API CollationElementIterator : public UObject {
public: 

    // CollationElementIterator public data member ------------------------------

    enum {
        /**
         * NULLORDER indicates that an error has occured while processing
         * @stable ICU 2.0
         */
        NULLORDER = (int32_t)0xffffffff
    };

    // CollationElementIterator public constructor/destructor -------------------

    /**
    * Copy constructor.
    *
    * @param other    the object to be copied from
    * @stable ICU 2.0
    */
    CollationElementIterator(const CollationElementIterator& other);

    /** 
    * Destructor
    * @stable ICU 2.0
    */
    virtual ~CollationElementIterator();

    // CollationElementIterator public methods ----------------------------------

    /**
    * Returns true if "other" is the same as "this"
    *
    * @param other    the object to be compared
    * @return         true if "other" is the same as "this"
    * @stable ICU 2.0
    */
    UBool operator==(const CollationElementIterator& other) const;

    /**
    * Returns true if "other" is not the same as "this".
    *
    * @param other    the object to be compared
    * @return         true if "other" is not the same as "this"
    * @stable ICU 2.0
    */
    UBool operator!=(const CollationElementIterator& other) const;

    /**
    * Resets the cursor to the beginning of the string.
    * @stable ICU 2.0
    */
    void reset(void);

    /**
    * Gets the ordering priority of the next character in the string.
    * @param status the error code status.
    * @return the next character's ordering. otherwise returns NULLORDER if an 
    *         error has occured or if the end of string has been reached
    * @stable ICU 2.0
    */
    int32_t next(UErrorCode& status);

    /**
    * Get the ordering priority of the previous collation element in the string.
    * @param status the error code status.
    * @return the previous element's ordering. otherwise returns NULLORDER if an 
    *         error has occured or if the start of string has been reached
    * @stable ICU 2.0
    */
    int32_t previous(UErrorCode& status);

    /**
    * Gets the primary order of a collation order.
    * @param order the collation order
    * @return the primary order of a collation order.
    * @stable ICU 2.0
    */
    static inline int32_t primaryOrder(int32_t order);

    /**
    * Gets the secondary order of a collation order.
    * @param order the collation order
    * @return the secondary order of a collation order.
    * @stable ICU 2.0
    */
    static inline int32_t secondaryOrder(int32_t order);

    /**
    * Gets the tertiary order of a collation order.
    * @param order the collation order
    * @return the tertiary order of a collation order.
    * @stable ICU 2.0
    */
    static inline int32_t tertiaryOrder(int32_t order);

    /**
    * Return the maximum length of any expansion sequences that end with the 
    * specified comparison order.
    * @param order a collation order returned by previous or next.
    * @return maximum size of the expansion sequences ending with the collation 
    *         element or 1 if collation element does not occur at the end of any 
    *         expansion sequence
    * @stable ICU 2.0
    */
    int32_t getMaxExpansion(int32_t order) const;

    /**
    * Gets the comparison order in the desired strength. Ignore the other
    * differences.
    * @param order The order value
    * @stable ICU 2.0
    */
    int32_t strengthOrder(int32_t order) const;

    /**
    * Sets the source string.
    * @param str the source string.
    * @param status the error code status.
    * @stable ICU 2.0
    */
    void setText(const UnicodeString& str, UErrorCode& status);

    /**
    * Sets the source string.
    * @param str the source character iterator.
    * @param status the error code status.
    * @stable ICU 2.0
    */
    void setText(CharacterIterator& str, UErrorCode& status);

    /**
    * Checks if a comparison order is ignorable.
    * @param order the collation order.
    * @return TRUE if a character is ignorable, FALSE otherwise.
    * @stable ICU 2.0
    */
    static inline UBool isIgnorable(int32_t order);

    /**
    * Gets the offset of the currently processed character in the source string.
    * @return the offset of the character.
    * @stable ICU 2.0
    */
    int32_t getOffset(void) const;

    /**
    * Sets the offset of the currently processed character in the source string.
    * @param newOffset the new offset.
    * @param status the error code status.
    * @return the offset of the character.
    * @stable ICU 2.0
    */
    void setOffset(int32_t newOffset, UErrorCode& status);

    /**
    * ICU "poor man's RTTI", returns a UClassID for the actual class.
    *
    * @stable ICU 2.2
    */
    virtual UClassID getDynamicClassID() const;

    /**
    * ICU "poor man's RTTI", returns a UClassID for this class.
    *
    * @stable ICU 2.2
    */
    static UClassID U_EXPORT2 getStaticClassID();

protected:
  
    // CollationElementIterator protected constructors --------------------------
    /**
    * @stable ICU 2.0
    */
    friend class RuleBasedCollator;

    /**
    * CollationElementIterator constructor. This takes the source string and the 
    * collation object. The cursor will walk thru the source string based on the 
    * predefined collation rules. If the source string is empty, NULLORDER will 
    * be returned on the calls to next().
    * @param sourceText    the source string.
    * @param order         the collation object.
    * @param status        the error code status.
    * @stable ICU 2.0
    */
    CollationElementIterator(const UnicodeString& sourceText,
        const RuleBasedCollator* order, UErrorCode& status);

    /**
    * CollationElementIterator constructor. This takes the source string and the 
    * collation object.  The cursor will walk thru the source string based on the 
    * predefined collation rules.  If the source string is empty, NULLORDER will 
    * be returned on the calls to next().
    * @param sourceText    the source string.
    * @param order         the collation object.
    * @param status        the error code status.
    * @stable ICU 2.0
    */
    CollationElementIterator(const CharacterIterator& sourceText,
        const RuleBasedCollator* order, UErrorCode& status);

    // CollationElementIterator protected methods -------------------------------

    /**
    * Assignment operator
    *
    * @param other    the object to be copied
    * @stable ICU 2.0
    */
    const CollationElementIterator&
        operator=(const CollationElementIterator& other);

private:
    CollationElementIterator(); // default constructor not implemented

    // CollationElementIterator private data members ----------------------------

    /**
    * Data wrapper for collation elements
    */
    UCollationElements *m_data_;

    /**
    * Indicates if m_data_ belongs to this object.
    */
    UBool isDataOwned_;

};

// CollationElementIterator inline method defination --------------------------

/**
* Get the primary order of a collation order.
* @param order the collation order
* @return the primary order of a collation order.
*/
inline int32_t CollationElementIterator::primaryOrder(int32_t order)
{
    order &= RuleBasedCollator::PRIMARYORDERMASK;
    return (order >> RuleBasedCollator::PRIMARYORDERSHIFT);
}

/**
* Get the secondary order of a collation order.
* @param order the collation order
* @return the secondary order of a collation order.
*/
inline int32_t CollationElementIterator::secondaryOrder(int32_t order)
{
    order = order & RuleBasedCollator::SECONDARYORDERMASK;
    return (order >> RuleBasedCollator::SECONDARYORDERSHIFT);
}

/**
* Get the tertiary order of a collation order.
* @param order the collation order
* @return the tertiary order of a collation order.
*/
inline int32_t CollationElementIterator::tertiaryOrder(int32_t order)
{
    return (order &= RuleBasedCollator::TERTIARYORDERMASK);
}

inline int32_t CollationElementIterator::getMaxExpansion(int32_t order) const
{
    return ucol_getMaxExpansion(m_data_, (uint32_t)order);
}

inline UBool CollationElementIterator::isIgnorable(int32_t order)
{
    return (primaryOrder(order) == RuleBasedCollator::PRIMIGNORABLE);
}

U_NAMESPACE_END

#endif /* #if !UCONFIG_NO_COLLATION */

#endif