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