icuSources/common/unicode/caniter.h

   1 /*
   2  *******************************************************************************
   3  * Copyright (C) 1996-2006, International Business Machines Corporation and    *
   4  * others. All Rights Reserved.                                                *
   5  *******************************************************************************
   6  */
   7
   8 #ifndef CANITER_H
   9 #define CANITER_H
  10
  11 #include "unicode/utypes.h"
  12
  13 #if !UCONFIG_NO_NORMALIZATION
  14
  15 #include "unicode/uobject.h"
  16 #include "unicode/unistr.h"
  17
  18 /**
  19  * \file
  20  * \brief C++ API: Canonical Iterator
  21  */
  22
  23 /** Should permutation skip characters with combining class zero
  24  *  Should be either TRUE or FALSE. This is a compile time option
  25  *  @stable ICU 2.4
  26  */
  27 #ifndef CANITER_SKIP_ZEROES
  28 #define CANITER_SKIP_ZEROES TRUE
  29 #endif
  30
  31 U_NAMESPACE_BEGIN
  32
  33 class Hashtable;
  34
  35 /**
  36  * This class allows one to iterate through all the strings that are canonically equivalent to a given
  37  * string. For example, here are some sample results:
  38 Results for: {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
  39 1: \\u0041\\u030A\\u0064\\u0307\\u0327
  40  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
  41 2: \\u0041\\u030A\\u0064\\u0327\\u0307
  42  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
  43 3: \\u0041\\u030A\\u1E0B\\u0327
  44  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
  45 4: \\u0041\\u030A\\u1E11\\u0307
  46  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
  47 5: \\u00C5\\u0064\\u0307\\u0327
  48  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
  49 6: \\u00C5\\u0064\\u0327\\u0307
  50  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
  51 7: \\u00C5\\u1E0B\\u0327
  52  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
  53 8: \\u00C5\\u1E11\\u0307
  54  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
  55 9: \\u212B\\u0064\\u0307\\u0327
  56  = {ANGSTROM SIGN}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
  57 10: \\u212B\\u0064\\u0327\\u0307
  58  = {ANGSTROM SIGN}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
  59 11: \\u212B\\u1E0B\\u0327
  60  = {ANGSTROM SIGN}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
  61 12: \\u212B\\u1E11\\u0307
  62  = {ANGSTROM SIGN}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
  63  *<br>Note: the code is intended for use with small strings, and is not suitable for larger ones,
  64  * since it has not been optimized for that situation.
  65  * Note, CanonicalIterator is not intended to be subclassed.
  66  * @author M. Davis
  67  * @author C++ port by V. Weinstein
  68  * @stable ICU 2.4
  69  */
  70 class U_COMMON_API CanonicalIterator : public UObject {
  71 public:
  72     /**
  73      * Construct a CanonicalIterator object
  74      * @param source    string to get results for
  75      * @param status    Fill-in parameter which receives the status of this operation.
  76      * @stable ICU 2.4
  77      */
  78     CanonicalIterator(const UnicodeString &source, UErrorCode &status);
  79
  80     /** Destructor
  81      *  Cleans pieces
  82      * @stable ICU 2.4
  83      */
  84     virtual ~CanonicalIterator();
  85
  86     /**
  87      * Gets the NFD form of the current source we are iterating over.
  88      * @return gets the source: NOTE: it is the NFD form of source
  89      * @stable ICU 2.4
  90      */
  91     UnicodeString getSource();
  92
  93     /**
  94      * Resets the iterator so that one can start again from the beginning.
  95      * @stable ICU 2.4
  96      */
  97     void reset();
  98
  99     /**
 100      * Get the next canonically equivalent string.
 101      * <br><b>Warning: The strings are not guaranteed to be in any particular order.</b>
 102      * @return the next string that is canonically equivalent. A bogus string is returned when
 103      * the iteration is done.
 104      * @stable ICU 2.4
 105      */
 106     UnicodeString next();
 107
 108     /**
 109      * Set a new source for this iterator. Allows object reuse.
 110      * @param newSource     the source string to iterate against. This allows the same iterator to be used
 111      *                     while changing the source string, saving object creation.
 112      * @param status        Fill-in parameter which receives the status of this operation.
 113      * @stable ICU 2.4
 114      */
 115     void setSource(const UnicodeString &newSource, UErrorCode &status);
 116
 117     /**
 118      * Dumb recursive implementation of permutation.
 119      * TODO: optimize
 120      * @param source     the string to find permutations for
 121      * @param skipZeros  determine if skip zeros
 122      * @param result     the results in a set.
 123      * @param status       Fill-in parameter which receives the status of this operation.
 124      * @internal
 125      */
 126     static void U_EXPORT2 permute(UnicodeString &source, UBool skipZeros, Hashtable *result, UErrorCode &status);
 127
 128     /**
 129      * ICU "poor man's RTTI", returns a UClassID for this class.
 130      *
 131      * @stable ICU 2.2
 132      */
 133     static UClassID U_EXPORT2 getStaticClassID();
 134
 135     /**
 136      * ICU "poor man's RTTI", returns a UClassID for the actual class.
 137      *
 138      * @stable ICU 2.2
 139      */
 140     virtual UClassID getDynamicClassID() const;
 141
 142 private:
 143     // ===================== PRIVATES ==============================
 144     // private default constructor
 145     CanonicalIterator();
 146
 147
 148     /**
 149      * Copy constructor. Private for now.
 150      * @internal
 151      */
 152     CanonicalIterator(const CanonicalIterator& other);
 153
 154     /**
 155      * Assignment operator. Private for now.
 156      * @internal
 157      */
 158     CanonicalIterator& operator=(const CanonicalIterator& other);
 159
 160     // fields
 161     UnicodeString source;
 162     UBool done;
 163
 164     // 2 dimensional array holds the pieces of the string with
 165     // their different canonically equivalent representations
 166     UnicodeString **pieces;
 167     int32_t pieces_length;
 168     int32_t *pieces_lengths;
 169
 170     // current is used in iterating to combine pieces
 171     int32_t *current;
 172     int32_t current_length;
 173
 174     // transient fields
 175     UnicodeString buffer;
 176
 177     // we have a segment, in NFD. Find all the strings that are canonically equivalent to it.
 178     UnicodeString *getEquivalents(const UnicodeString &segment, int32_t &result_len, UErrorCode &status); //private String[] getEquivalents(String segment)
 179
 180     //Set getEquivalents2(String segment);
 181     Hashtable *getEquivalents2(Hashtable *fillinResult, const UChar *segment, int32_t segLen, UErrorCode &status);
 182     //Hashtable *getEquivalents2(const UnicodeString &segment, int32_t segLen, UErrorCode &status);
 183
 184     /**
 185      * See if the decomposition of cp2 is at segment starting at segmentPos
 186      * (with canonical rearrangment!)
 187      * If so, take the remainder, and return the equivalents
 188      */
 189     //Set extract(int comp, String segment, int segmentPos, StringBuffer buffer);
 190     Hashtable *extract(Hashtable *fillinResult, UChar32 comp, const UChar *segment, int32_t segLen, int32_t segmentPos, UErrorCode &status);
 191     //Hashtable *extract(UChar32 comp, const UnicodeString &segment, int32_t segLen, int32_t segmentPos, UErrorCode &status);
 192
 193     void cleanPieces();
 194
 195 };
 196
 197 U_NAMESPACE_END
 198
 199 #endif /* #if !UCONFIG_NO_NORMALIZATION */
 200
 201 #endif