icuSources/common/unicode/caniter.h

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4  *******************************************************************************
   5  * Copyright (C) 1996-2014, International Business Machines Corporation and
   6  * others. All Rights Reserved.
   7  *******************************************************************************
   8  */
   9
  10 #ifndef CANITER_H
  11 #define CANITER_H
  12
  13 #include "unicode/utypes.h"
  14
  15 #if U_SHOW_CPLUSPLUS_API
  16
  17 #if !UCONFIG_NO_NORMALIZATION
  18
  19 #include "unicode/uobject.h"
  20 #include "unicode/unistr.h"
  21
  22 /**
  23  * \file
  24  * \brief C++ API: Canonical Iterator
  25  */
  26
  27 /** Should permutation skip characters with combining class zero
  28  *  Should be either TRUE or FALSE. This is a compile time option
  29  *  @stable ICU 2.4
  30  */
  31 #ifndef CANITER_SKIP_ZEROES
  32 #define CANITER_SKIP_ZEROES TRUE
  33 #endif
  34
  35 U_NAMESPACE_BEGIN
  36
  37 class Hashtable;
  38 class Normalizer2;
  39 class Normalizer2Impl;
  40
  41 /**
  42  * This class allows one to iterate through all the strings that are canonically equivalent to a given
  43  * string. For example, here are some sample results:
  44 Results for: {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
  45 1: \\u0041\\u030A\\u0064\\u0307\\u0327
  46  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
  47 2: \\u0041\\u030A\\u0064\\u0327\\u0307
  48  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
  49 3: \\u0041\\u030A\\u1E0B\\u0327
  50  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
  51 4: \\u0041\\u030A\\u1E11\\u0307
  52  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
  53 5: \\u00C5\\u0064\\u0307\\u0327
  54  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
  55 6: \\u00C5\\u0064\\u0327\\u0307
  56  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
  57 7: \\u00C5\\u1E0B\\u0327
  58  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
  59 8: \\u00C5\\u1E11\\u0307
  60  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
  61 9: \\u212B\\u0064\\u0307\\u0327
  62  = {ANGSTROM SIGN}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
  63 10: \\u212B\\u0064\\u0327\\u0307
  64  = {ANGSTROM SIGN}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
  65 11: \\u212B\\u1E0B\\u0327
  66  = {ANGSTROM SIGN}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
  67 12: \\u212B\\u1E11\\u0307
  68  = {ANGSTROM SIGN}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
  69  *<br>Note: the code is intended for use with small strings, and is not suitable for larger ones,
  70  * since it has not been optimized for that situation.
  71  * Note, CanonicalIterator is not intended to be subclassed.
  72  * @author M. Davis
  73  * @author C++ port by V. Weinstein
  74  * @stable ICU 2.4
  75  */
  76 class U_COMMON_API CanonicalIterator U_FINAL : public UObject {
  77 public:
  78     /**
  79      * Construct a CanonicalIterator object
  80      * @param source    string to get results for
  81      * @param status    Fill-in parameter which receives the status of this operation.
  82      * @stable ICU 2.4
  83      */
  84     CanonicalIterator(const UnicodeString &source, UErrorCode &status);
  85
  86     /** Destructor
  87      *  Cleans pieces
  88      * @stable ICU 2.4
  89      */
  90     virtual ~CanonicalIterator();
  91
  92     /**
  93      * Gets the NFD form of the current source we are iterating over.
  94      * @return gets the source: NOTE: it is the NFD form of source
  95      * @stable ICU 2.4
  96      */
  97     UnicodeString getSource();
  98
  99     /**
 100      * Resets the iterator so that one can start again from the beginning.
 101      * @stable ICU 2.4
 102      */
 103     void reset();
 104
 105     /**
 106      * Get the next canonically equivalent string.
 107      * <br><b>Warning: The strings are not guaranteed to be in any particular order.</b>
 108      * @return the next string that is canonically equivalent. A bogus string is returned when
 109      * the iteration is done.
 110      * @stable ICU 2.4
 111      */
 112     UnicodeString next();
 113
 114     /**
 115      * Set a new source for this iterator. Allows object reuse.
 116      * @param newSource     the source string to iterate against. This allows the same iterator to be used
 117      *                     while changing the source string, saving object creation.
 118      * @param status        Fill-in parameter which receives the status of this operation.
 119      * @stable ICU 2.4
 120      */
 121     void setSource(const UnicodeString &newSource, UErrorCode &status);
 122
 123 #ifndef U_HIDE_INTERNAL_API
 124     /**
 125      * Dumb recursive implementation of permutation.
 126      * TODO: optimize
 127      * @param source     the string to find permutations for
 128      * @param skipZeros  determine if skip zeros
 129      * @param result     the results in a set.
 130      * @param status       Fill-in parameter which receives the status of this operation.
 131      * @internal
 132      */
 133     static void U_EXPORT2 permute(UnicodeString &source, UBool skipZeros, Hashtable *result, UErrorCode &status);
 134 #endif  /* U_HIDE_INTERNAL_API */
 135
 136     /**
 137      * ICU "poor man's RTTI", returns a UClassID for this class.
 138      *
 139      * @stable ICU 2.2
 140      */
 141     static UClassID U_EXPORT2 getStaticClassID();
 142
 143     /**
 144      * ICU "poor man's RTTI", returns a UClassID for the actual class.
 145      *
 146      * @stable ICU 2.2
 147      */
 148     virtual UClassID getDynamicClassID() const;
 149
 150 private:
 151     // ===================== PRIVATES ==============================
 152     // private default constructor
 153     CanonicalIterator();
 154
 155
 156     /**
 157      * Copy constructor. Private for now.
 158      * @internal (private)
 159      */
 160     CanonicalIterator(const CanonicalIterator& other);
 161
 162     /**
 163      * Assignment operator. Private for now.
 164      * @internal (private)
 165      */
 166     CanonicalIterator& operator=(const CanonicalIterator& other);
 167
 168     // fields
 169     UnicodeString source;
 170     UBool done;
 171
 172     // 2 dimensional array holds the pieces of the string with
 173     // their different canonically equivalent representations
 174     UnicodeString **pieces;
 175     int32_t pieces_length;
 176     int32_t *pieces_lengths;
 177
 178     // current is used in iterating to combine pieces
 179     int32_t *current;
 180     int32_t current_length;
 181
 182     // transient fields
 183     UnicodeString buffer;
 184
 185     const Normalizer2 &nfd;
 186     const Normalizer2Impl &nfcImpl;
 187
 188     // we have a segment, in NFD. Find all the strings that are canonically equivalent to it.
 189     UnicodeString *getEquivalents(const UnicodeString &segment, int32_t &result_len, UErrorCode &status); //private String[] getEquivalents(String segment)
 190
 191     //Set getEquivalents2(String segment);
 192     Hashtable *getEquivalents2(Hashtable *fillinResult, const char16_t *segment, int32_t segLen, UErrorCode &status);
 193     //Hashtable *getEquivalents2(const UnicodeString &segment, int32_t segLen, UErrorCode &status);
 194
 195     /**
 196      * See if the decomposition of cp2 is at segment starting at segmentPos
 197      * (with canonical rearrangment!)
 198      * If so, take the remainder, and return the equivalents
 199      */
 200     //Set extract(int comp, String segment, int segmentPos, StringBuffer buffer);
 201     Hashtable *extract(Hashtable *fillinResult, UChar32 comp, const char16_t *segment, int32_t segLen, int32_t segmentPos, UErrorCode &status);
 202     //Hashtable *extract(UChar32 comp, const UnicodeString &segment, int32_t segLen, int32_t segmentPos, UErrorCode &status);
 203
 204     void cleanPieces();
 205
 206 };
 207
 208 U_NAMESPACE_END
 209
 210 #endif /* #if !UCONFIG_NO_NORMALIZATION */
 211
 212 #endif /* U_SHOW_CPLUSPLUS_API */
 213
 214 #endif