source/i18n/brktrans.cpp

   1 // Copyright (C) 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4 **********************************************************************
   5 *   Copyright (C) 2008-2015, International Business Machines
   6 *   Corporation and others.  All Rights Reserved.
   7 **********************************************************************
   8 *   Date        Name        Description
   9 *   05/11/2008  Andy Heninger  Port from Java
  10 **********************************************************************
  11 */
  12
  13 #include "unicode/utypes.h"
  14
  15 #if  !UCONFIG_NO_TRANSLITERATION && !UCONFIG_NO_BREAK_ITERATION
  16
  17 #include "unicode/brkiter.h"
  18 #include "unicode/localpointer.h"
  19 #include "unicode/uchar.h"
  20 #include "unicode/unifilt.h"
  21 #include "unicode/uniset.h"
  22
  23 #include "brktrans.h"
  24 #include "cmemory.h"
  25 #include "mutex.h"
  26 #include "uprops.h"
  27 #include "uinvchar.h"
  28 #include "util.h"
  29 #include "uvectr32.h"
  30
  31 U_NAMESPACE_BEGIN
  32
  33 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(BreakTransliterator)
  34
  35 static const UChar SPACE       = 32;  // ' '
  36
  37
  38 /**
  39  * Constructs a transliterator with the default delimiters '{' and
  40  * '}'.
  41  */
  42 BreakTransliterator::BreakTransliterator(UnicodeFilter* adoptedFilter) :
  43         Transliterator(UNICODE_STRING("Any-BreakInternal", 17), adoptedFilter),
  44         cachedBI(NULL), cachedBoundaries(NULL), fInsertion(SPACE) {
  45     }
  46
  47
  48 /**
  49  * Destructor.
  50  */
  51 BreakTransliterator::~BreakTransliterator() {
  52 }
  53
  54 /**
  55  * Copy constructor.
  56  */
  57 BreakTransliterator::BreakTransliterator(const BreakTransliterator& o) :
  58         Transliterator(o), cachedBI(NULL), cachedBoundaries(NULL), fInsertion(o.fInsertion) {
  59 }
  60
  61
  62 /**
  63  * Transliterator API.
  64  */
  65 Transliterator* BreakTransliterator::clone(void) const {
  66     return new BreakTransliterator(*this);
  67 }
  68
  69 /**
  70  * Implements {@link Transliterator#handleTransliterate}.
  71  */
  72 void BreakTransliterator::handleTransliterate(Replaceable& text, UTransPosition& offsets,
  73                                                     UBool isIncremental ) const {
  74
  75         UErrorCode status = U_ZERO_ERROR;
  76         LocalPointer<BreakIterator> bi;
  77         LocalPointer<UVector32> boundaries;
  78
  79         {
  80             Mutex m;
  81             BreakTransliterator *nonConstThis = const_cast<BreakTransliterator *>(this);
  82             boundaries.moveFrom(nonConstThis->cachedBoundaries);
  83             bi.moveFrom(nonConstThis->cachedBI);
  84         }
  85         if (bi.isNull()) {
  86             bi.adoptInstead(BreakIterator::createWordInstance(Locale::getEnglish(), status));
  87         }
  88         if (boundaries.isNull()) {
  89             boundaries.adoptInstead(new UVector32(status));
  90         }
  91
  92         if (bi.isNull() || boundaries.isNull() || U_FAILURE(status)) {
  93             return;
  94         }
  95
  96         boundaries->removeAllElements();
  97         UnicodeString sText = replaceableAsString(text);
  98         bi->setText(sText);
  99         bi->preceding(offsets.start);
 100
 101         // To make things much easier, we will stack the boundaries, and then insert at the end.
 102         // generally, we won't need too many, since we will be filtered.
 103
 104         int32_t boundary;
 105         for(boundary = bi->next(); boundary != UBRK_DONE && boundary < offsets.limit; boundary = bi->next()) {
 106             if (boundary == 0) continue;
 107             // HACK: Check to see that preceeding item was a letter
 108
 109             UChar32 cp = sText.char32At(boundary-1);
 110             int type = u_charType(cp);
 111             //System.out.println(Integer.toString(cp,16) + " (before): " + type);
 112             if ((U_MASK(type) & (U_GC_L_MASK | U_GC_M_MASK)) == 0) continue;
 113
 114             cp = sText.char32At(boundary);
 115             type = u_charType(cp);
 116             //System.out.println(Integer.toString(cp,16) + " (after): " + type);
 117             if ((U_MASK(type) & (U_GC_L_MASK | U_GC_M_MASK)) == 0) continue;
 118
 119             boundaries->addElement(boundary, status);
 120             // printf("Boundary at %d\n", boundary);
 121         }
 122
 123         int delta = 0;
 124         int lastBoundary = 0;
 125
 126         if (boundaries->size() != 0) { // if we found something, adjust
 127             delta = boundaries->size() * fInsertion.length();
 128             lastBoundary = boundaries->lastElementi();
 129
 130             // we do this from the end backwards, so that we don't have to keep updating.
 131
 132             while (boundaries->size() > 0) {
 133                 boundary = boundaries->popi();
 134                 text.handleReplaceBetween(boundary, boundary, fInsertion);
 135             }
 136         }
 137
 138         // Now fix up the return values
 139         offsets.contextLimit += delta;
 140         offsets.limit += delta;
 141         offsets.start = isIncremental ? lastBoundary + delta : offsets.limit;
 142
 143         // Return break iterator & boundaries vector to the cache.
 144         {
 145             Mutex m;
 146             BreakTransliterator *nonConstThis = const_cast<BreakTransliterator *>(this);
 147             if (nonConstThis->cachedBI.isNull()) {
 148                 nonConstThis->cachedBI.moveFrom(bi);
 149             }
 150             if (nonConstThis->cachedBoundaries.isNull()) {
 151                 nonConstThis->cachedBoundaries.moveFrom(boundaries);
 152             }
 153         }
 154
 155         // TODO:  do something with U_FAILURE(status);
 156         //        (need to look at transliterators overall, not just here.)
 157 }
 158
 159 //
 160 //  getInsertion()
 161 //
 162 const UnicodeString &BreakTransliterator::getInsertion() const {
 163     return fInsertion;
 164 }
 165
 166 //
 167 //  setInsertion()
 168 //
 169 void BreakTransliterator::setInsertion(const UnicodeString &insertion) {
 170     this->fInsertion = insertion;
 171 }
 172
 173 //
 174 //   replaceableAsString   Hack to let break iterators work
 175 //                         on the replaceable text from transliterators.
 176 //                         In practice, the only real Replaceable type that we
 177 //                         will be seeing is UnicodeString, so this function
 178 //                         will normally be efficient.
 179 //
 180 UnicodeString BreakTransliterator::replaceableAsString(Replaceable &r) {
 181     UnicodeString s;
 182     UnicodeString *rs = dynamic_cast<UnicodeString *>(&r);
 183     if (rs != NULL) {
 184         s = *rs;
 185     } else {
 186         r.extractBetween(0, r.length(), s);
 187     }
 188     return s;
 189 }
 190
 191 U_NAMESPACE_END
 192
 193 #endif /* #if !UCONFIG_NO_TRANSLITERATION */