| /** |
| ******************************************************************************* |
| * Copyright (C) 2006-2008, International Business Machines Corporation and others. * |
| * All Rights Reserved. * |
| ******************************************************************************* |
| */ |
| |
| #include "unicode/utypes.h" |
| |
| #if !UCONFIG_NO_BREAK_ITERATION |
| |
| #include "brkeng.h" |
| #include "dictbe.h" |
| #include "unicode/uniset.h" |
| #include "unicode/chariter.h" |
| #include "unicode/ubrk.h" |
| #include "uvector.h" |
| #include "triedict.h" |
| #include "uassert.h" |
| #include "unicode/normlzr.h" |
| #include "cmemory.h" |
| |
| U_NAMESPACE_BEGIN |
| |
| /* |
| ****************************************************************** |
| */ |
| |
| /*DictionaryBreakEngine::DictionaryBreakEngine() { |
| fTypes = 0; |
| }*/ |
| |
| DictionaryBreakEngine::DictionaryBreakEngine(uint32_t breakTypes) { |
| fTypes = breakTypes; |
| } |
| |
| DictionaryBreakEngine::~DictionaryBreakEngine() { |
| } |
| |
| UBool |
| DictionaryBreakEngine::handles(UChar32 c, int32_t breakType) const { |
| return (breakType >= 0 && breakType < 32 && (((uint32_t)1 << breakType) & fTypes) |
| && fSet.contains(c)); |
| } |
| |
| int32_t |
| DictionaryBreakEngine::findBreaks( UText *text, |
| int32_t startPos, |
| int32_t endPos, |
| UBool reverse, |
| int32_t breakType, |
| UStack &foundBreaks ) const { |
| int32_t result = 0; |
| |
| // Find the span of characters included in the set. |
| int32_t start = (int32_t)utext_getNativeIndex(text); |
| int32_t current; |
| int32_t rangeStart; |
| int32_t rangeEnd; |
| UChar32 c = utext_current32(text); |
| if (reverse) { |
| UBool isDict = fSet.contains(c); |
| while((current = (int32_t)utext_getNativeIndex(text)) > startPos && isDict) { |
| c = utext_previous32(text); |
| isDict = fSet.contains(c); |
| } |
| rangeStart = (current < startPos) ? startPos : current+(isDict ? 0 : 1); |
| rangeEnd = start + 1; |
| } |
| else { |
| while((current = (int32_t)utext_getNativeIndex(text)) < endPos && fSet.contains(c)) { |
| utext_next32(text); // TODO: recast loop for postincrement |
| c = utext_current32(text); |
| } |
| rangeStart = start; |
| rangeEnd = current; |
| } |
| if (breakType >= 0 && breakType < 32 && (((uint32_t)1 << breakType) & fTypes)) { |
| result = divideUpDictionaryRange(text, rangeStart, rangeEnd, foundBreaks); |
| utext_setNativeIndex(text, current); |
| } |
| |
| return result; |
| } |
| |
| void |
| DictionaryBreakEngine::setCharacters( const UnicodeSet &set ) { |
| fSet = set; |
| // Compact for caching |
| fSet.compact(); |
| } |
| |
| /*void |
| DictionaryBreakEngine::setBreakTypes( uint32_t breakTypes ) { |
| fTypes = breakTypes; |
| }*/ |
| |
| /* |
| ****************************************************************** |
| */ |
| |
| |
| // Helper class for improving readability of the Thai word break |
| // algorithm. The implementation is completely inline. |
| |
| // List size, limited by the maximum number of words in the dictionary |
| // that form a nested sequence. |
| #define POSSIBLE_WORD_LIST_MAX 20 |
| |
| class PossibleWord { |
| private: |
| // list of word candidate lengths, in increasing length order |
| int32_t lengths[POSSIBLE_WORD_LIST_MAX]; |
| int count; // Count of candidates |
| int32_t prefix; // The longest match with a dictionary word |
| int32_t offset; // Offset in the text of these candidates |
| int mark; // The preferred candidate's offset |
| int current; // The candidate we're currently looking at |
| |
| public: |
| PossibleWord(); |
| ~PossibleWord(); |
| |
| // Fill the list of candidates if needed, select the longest, and return the number found |
| int candidates( UText *text, const TrieWordDictionary *dict, int32_t rangeEnd ); |
| |
| // Select the currently marked candidate, point after it in the text, and invalidate self |
| int32_t acceptMarked( UText *text ); |
| |
| // Back up from the current candidate to the next shorter one; return TRUE if that exists |
| // and point the text after it |
| UBool backUp( UText *text ); |
| |
| // Return the longest prefix this candidate location shares with a dictionary word |
| int32_t longestPrefix(); |
| |
| // Mark the current candidate as the one we like |
| void markCurrent(); |
| }; |
| |
| inline |
| PossibleWord::PossibleWord() { |
| offset = -1; |
| } |
| |
| inline |
| PossibleWord::~PossibleWord() { |
| } |
| |
| inline int |
| PossibleWord::candidates( UText *text, const TrieWordDictionary *dict, int32_t rangeEnd ) { |
| // TODO: If getIndex is too slow, use offset < 0 and add discardAll() |
| int32_t start = (int32_t)utext_getNativeIndex(text); |
| if (start != offset) { |
| offset = start; |
| prefix = dict->matches(text, rangeEnd-start, lengths, count, sizeof(lengths)/sizeof(lengths[0])); |
| // Dictionary leaves text after longest prefix, not longest word. Back up. |
| if (count <= 0) { |
| utext_setNativeIndex(text, start); |
| } |
| } |
| if (count > 0) { |
| utext_setNativeIndex(text, start+lengths[count-1]); |
| } |
| current = count-1; |
| mark = current; |
| return count; |
| } |
| |
| inline int32_t |
| PossibleWord::acceptMarked( UText *text ) { |
| utext_setNativeIndex(text, offset + lengths[mark]); |
| return lengths[mark]; |
| } |
| |
| inline UBool |
| PossibleWord::backUp( UText *text ) { |
| if (current > 0) { |
| utext_setNativeIndex(text, offset + lengths[--current]); |
| return TRUE; |
| } |
| return FALSE; |
| } |
| |
| inline int32_t |
| PossibleWord::longestPrefix() { |
| return prefix; |
| } |
| |
| inline void |
| PossibleWord::markCurrent() { |
| mark = current; |
| } |
| |
| // How many words in a row are "good enough"? |
| #define THAI_LOOKAHEAD 3 |
| |
| // Will not combine a non-word with a preceding dictionary word longer than this |
| #define THAI_ROOT_COMBINE_THRESHOLD 3 |
| |
| // Will not combine a non-word that shares at least this much prefix with a |
| // dictionary word, with a preceding word |
| #define THAI_PREFIX_COMBINE_THRESHOLD 3 |
| |
| // Ellision character |
| #define THAI_PAIYANNOI 0x0E2F |
| |
| // Repeat character |
| #define THAI_MAIYAMOK 0x0E46 |
| |
| // Minimum word size |
| #define THAI_MIN_WORD 2 |
| |
| // Minimum number of characters for two words |
| #define THAI_MIN_WORD_SPAN (THAI_MIN_WORD * 2) |
| |
| ThaiBreakEngine::ThaiBreakEngine(const TrieWordDictionary *adoptDictionary, UErrorCode &status) |
| : DictionaryBreakEngine((1<<UBRK_WORD) | (1<<UBRK_LINE)), |
| fDictionary(adoptDictionary) |
| { |
| fThaiWordSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Thai:]&[:LineBreak=SA:]]"), status); |
| if (U_SUCCESS(status)) { |
| setCharacters(fThaiWordSet); |
| } |
| fMarkSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Thai:]&[:LineBreak=SA:]&[:M:]]"), status); |
| fMarkSet.add(0x0020); |
| fEndWordSet = fThaiWordSet; |
| fEndWordSet.remove(0x0E31); // MAI HAN-AKAT |
| fEndWordSet.remove(0x0E40, 0x0E44); // SARA E through SARA AI MAIMALAI |
| fBeginWordSet.add(0x0E01, 0x0E2E); // KO KAI through HO NOKHUK |
| fBeginWordSet.add(0x0E40, 0x0E44); // SARA E through SARA AI MAIMALAI |
| fSuffixSet.add(THAI_PAIYANNOI); |
| fSuffixSet.add(THAI_MAIYAMOK); |
| |
| // Compact for caching. |
| fMarkSet.compact(); |
| fEndWordSet.compact(); |
| fBeginWordSet.compact(); |
| fSuffixSet.compact(); |
| } |
| |
| ThaiBreakEngine::~ThaiBreakEngine() { |
| delete fDictionary; |
| } |
| |
| int32_t |
| ThaiBreakEngine::divideUpDictionaryRange( UText *text, |
| int32_t rangeStart, |
| int32_t rangeEnd, |
| UStack &foundBreaks ) const { |
| if ((rangeEnd - rangeStart) < THAI_MIN_WORD_SPAN) { |
| return 0; // Not enough characters for two words |
| } |
| |
| uint32_t wordsFound = 0; |
| int32_t wordLength; |
| int32_t current; |
| UErrorCode status = U_ZERO_ERROR; |
| PossibleWord words[THAI_LOOKAHEAD]; |
| UChar32 uc; |
| |
| utext_setNativeIndex(text, rangeStart); |
| |
| while (U_SUCCESS(status) && (current = (int32_t)utext_getNativeIndex(text)) < rangeEnd) { |
| wordLength = 0; |
| |
| // Look for candidate words at the current position |
| int candidates = words[wordsFound%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd); |
| |
| // If we found exactly one, use that |
| if (candidates == 1) { |
| wordLength = words[wordsFound%THAI_LOOKAHEAD].acceptMarked(text); |
| wordsFound += 1; |
| } |
| |
| // If there was more than one, see which one can take us forward the most words |
| else if (candidates > 1) { |
| // If we're already at the end of the range, we're done |
| if ((int32_t)utext_getNativeIndex(text) >= rangeEnd) { |
| goto foundBest; |
| } |
| do { |
| int wordsMatched = 1; |
| if (words[(wordsFound+1)%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) > 0) { |
| if (wordsMatched < 2) { |
| // Followed by another dictionary word; mark first word as a good candidate |
| words[wordsFound%THAI_LOOKAHEAD].markCurrent(); |
| wordsMatched = 2; |
| } |
| |
| // If we're already at the end of the range, we're done |
| if ((int32_t)utext_getNativeIndex(text) >= rangeEnd) { |
| goto foundBest; |
| } |
| |
| // See if any of the possible second words is followed by a third word |
| do { |
| // If we find a third word, stop right away |
| if (words[(wordsFound+2)%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd)) { |
| words[wordsFound%THAI_LOOKAHEAD].markCurrent(); |
| goto foundBest; |
| } |
| } |
| while (words[(wordsFound+1)%THAI_LOOKAHEAD].backUp(text)); |
| } |
| } |
| while (words[wordsFound%THAI_LOOKAHEAD].backUp(text)); |
| foundBest: |
| wordLength = words[wordsFound%THAI_LOOKAHEAD].acceptMarked(text); |
| wordsFound += 1; |
| } |
| |
| // We come here after having either found a word or not. We look ahead to the |
| // next word. If it's not a dictionary word, we will combine it withe the word we |
| // just found (if there is one), but only if the preceding word does not exceed |
| // the threshold. |
| // The text iterator should now be positioned at the end of the word we found. |
| if ((int32_t)utext_getNativeIndex(text) < rangeEnd && wordLength < THAI_ROOT_COMBINE_THRESHOLD) { |
| // if it is a dictionary word, do nothing. If it isn't, then if there is |
| // no preceding word, or the non-word shares less than the minimum threshold |
| // of characters with a dictionary word, then scan to resynchronize |
| if (words[wordsFound%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) <= 0 |
| && (wordLength == 0 |
| || words[wordsFound%THAI_LOOKAHEAD].longestPrefix() < THAI_PREFIX_COMBINE_THRESHOLD)) { |
| // Look for a plausible word boundary |
| //TODO: This section will need a rework for UText. |
| int32_t remaining = rangeEnd - (current+wordLength); |
| UChar32 pc = utext_current32(text); |
| int32_t chars = 0; |
| for (;;) { |
| utext_next32(text); |
| uc = utext_current32(text); |
| // TODO: Here we're counting on the fact that the SA languages are all |
| // in the BMP. This should get fixed with the UText rework. |
| chars += 1; |
| if (--remaining <= 0) { |
| break; |
| } |
| if (fEndWordSet.contains(pc) && fBeginWordSet.contains(uc)) { |
| // Maybe. See if it's in the dictionary. |
| // NOTE: In the original Apple code, checked that the next |
| // two characters after uc were not 0x0E4C THANTHAKHAT before |
| // checking the dictionary. That is just a performance filter, |
| // but it's not clear it's faster than checking the trie. |
| int candidates = words[(wordsFound+1)%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd); |
| utext_setNativeIndex(text, current+wordLength+chars); |
| if (candidates > 0) { |
| break; |
| } |
| } |
| pc = uc; |
| } |
| |
| // Bump the word count if there wasn't already one |
| if (wordLength <= 0) { |
| wordsFound += 1; |
| } |
| |
| // Update the length with the passed-over characters |
| wordLength += chars; |
| } |
| else { |
| // Back up to where we were for next iteration |
| utext_setNativeIndex(text, current+wordLength); |
| } |
| } |
| |
| // Never stop before a combining mark. |
| int32_t currPos; |
| while ((currPos = (int32_t)utext_getNativeIndex(text)) < rangeEnd && fMarkSet.contains(utext_current32(text))) { |
| utext_next32(text); |
| wordLength += (int32_t)utext_getNativeIndex(text) - currPos; |
| } |
| |
| // Look ahead for possible suffixes if a dictionary word does not follow. |
| // We do this in code rather than using a rule so that the heuristic |
| // resynch continues to function. For example, one of the suffix characters |
| // could be a typo in the middle of a word. |
| if ((int32_t)utext_getNativeIndex(text) < rangeEnd && wordLength > 0) { |
| if (words[wordsFound%THAI_LOOKAHEAD].candidates(text, fDictionary, rangeEnd) <= 0 |
| && fSuffixSet.contains(uc = utext_current32(text))) { |
| if (uc == THAI_PAIYANNOI) { |
| if (!fSuffixSet.contains(utext_previous32(text))) { |
| // Skip over previous end and PAIYANNOI |
| utext_next32(text); |
| utext_next32(text); |
| wordLength += 1; // Add PAIYANNOI to word |
| uc = utext_current32(text); // Fetch next character |
| } |
| else { |
| // Restore prior position |
| utext_next32(text); |
| } |
| } |
| if (uc == THAI_MAIYAMOK) { |
| if (utext_previous32(text) != THAI_MAIYAMOK) { |
| // Skip over previous end and MAIYAMOK |
| utext_next32(text); |
| utext_next32(text); |
| wordLength += 1; // Add MAIYAMOK to word |
| } |
| else { |
| // Restore prior position |
| utext_next32(text); |
| } |
| } |
| } |
| else { |
| utext_setNativeIndex(text, current+wordLength); |
| } |
| } |
| |
| // Did we find a word on this iteration? If so, push it on the break stack |
| if (wordLength > 0) { |
| foundBreaks.push((current+wordLength), status); |
| } |
| } |
| |
| // Don't return a break for the end of the dictionary range if there is one there. |
| if (foundBreaks.peeki() >= rangeEnd) { |
| (void) foundBreaks.popi(); |
| wordsFound -= 1; |
| } |
| |
| return wordsFound; |
| } |
| |
| /* |
| ****************************************************************** |
| * CjkBreakEngine |
| */ |
| static const uint32_t kuint32max = 0xFFFFFFFF; |
| CjkBreakEngine::CjkBreakEngine(const TrieWordDictionary *adoptDictionary, LanguageType type, UErrorCode &status) |
| : DictionaryBreakEngine(1<<UBRK_WORD), fDictionary(adoptDictionary){ |
| if (!adoptDictionary->getValued()) { |
| status = U_ILLEGAL_ARGUMENT_ERROR; |
| return; |
| } |
| |
| // Korean dictionary only includes Hangul syllables |
| fHangulWordSet.applyPattern(UNICODE_STRING_SIMPLE("[\\uac00-\\ud7a3]"), status); |
| fHanWordSet.applyPattern(UNICODE_STRING_SIMPLE("[:Han:]"), status); |
| fKatakanaWordSet.applyPattern(UNICODE_STRING_SIMPLE("[[:Katakana:]\\uff9e\\uff9f]"), status); |
| fHiraganaWordSet.applyPattern(UNICODE_STRING_SIMPLE("[:Hiragana:]"), status); |
| |
| if (U_SUCCESS(status)) { |
| // handle Korean and Japanese/Chinese using different dictionaries |
| if (type == kKorean) { |
| setCharacters(fHangulWordSet); |
| } else { //Chinese and Japanese |
| UnicodeSet cjSet; |
| cjSet.addAll(fHanWordSet); |
| cjSet.addAll(fKatakanaWordSet); |
| cjSet.addAll(fHiraganaWordSet); |
| cjSet.add(UNICODE_STRING_SIMPLE("\\uff70\\u30fc")); |
| setCharacters(cjSet); |
| } |
| } |
| } |
| |
| CjkBreakEngine::~CjkBreakEngine(){ |
| delete fDictionary; |
| } |
| |
| // The katakanaCost values below are based on the length frequencies of all |
| // katakana phrases in the dictionary |
| static const int kMaxKatakanaLength = 8; |
| static const int kMaxKatakanaGroupLength = 20; |
| static const uint32_t maxSnlp = 255; |
| |
| static inline uint32_t getKatakanaCost(int wordLength){ |
| //TODO: fill array with actual values from dictionary! |
| static const uint32_t katakanaCost[kMaxKatakanaLength + 1] |
| = {8192, 984, 408, 240, 204, 252, 300, 372, 480}; |
| return (wordLength > kMaxKatakanaLength) ? 8192 : katakanaCost[wordLength]; |
| } |
| |
| static inline bool isKatakana(uint16_t value) { |
| return (value >= 0x30A1u && value <= 0x30FEu && value != 0x30FBu) || |
| (value >= 0xFF66u && value <= 0xFF9fu); |
| } |
| |
| // A very simple helper class to streamline the buffer handling in |
| // divideUpDictionaryRange. |
| template<class T, size_t N> |
| class AutoBuffer { |
| public: |
| AutoBuffer(size_t size) : buffer(stackBuffer), capacity(N) { |
| if (size > N) { |
| buffer = reinterpret_cast<T*>(uprv_malloc(sizeof(T)*size)); |
| capacity = size; |
| } |
| } |
| ~AutoBuffer() { |
| if (buffer != stackBuffer) |
| uprv_free(buffer); |
| } |
| #if 0 |
| T* operator& () { |
| return buffer; |
| } |
| #endif |
| T* elems() { |
| return buffer; |
| } |
| const T& operator[] (size_t i) const { |
| return buffer[i]; |
| } |
| T& operator[] (size_t i) { |
| return buffer[i]; |
| } |
| |
| // resize without copy |
| void resize(size_t size) { |
| if (size <= capacity) |
| return; |
| if (buffer != stackBuffer) |
| uprv_free(buffer); |
| buffer = reinterpret_cast<T*>(uprv_malloc(sizeof(T)*size)); |
| capacity = size; |
| } |
| private: |
| T stackBuffer[N]; |
| T* buffer; |
| AutoBuffer(); |
| size_t capacity; |
| }; |
| |
| |
| /* |
| * @param text A UText representing the text |
| * @param rangeStart The start of the range of dictionary characters |
| * @param rangeEnd The end of the range of dictionary characters |
| * @param foundBreaks Output of C array of int32_t break positions, or 0 |
| * @return The number of breaks found |
| */ |
| int32_t |
| CjkBreakEngine::divideUpDictionaryRange( UText *text, |
| int32_t rangeStart, |
| int32_t rangeEnd, |
| UStack &foundBreaks ) const { |
| if (rangeStart >= rangeEnd) { |
| return 0; |
| } |
| |
| const size_t defaultInputLength = 80; |
| size_t inputLength = rangeEnd - rangeStart; |
| AutoBuffer<UChar, defaultInputLength> charString(inputLength); |
| |
| // Normalize the input string and put it in normalizedText. |
| // The map from the indices of the normalized input to the raw |
| // input is kept in charPositions. |
| UErrorCode status = U_ZERO_ERROR; |
| utext_extract(text, rangeStart, rangeEnd, charString.elems(), inputLength, &status); |
| if (U_FAILURE(status)) |
| return 0; |
| |
| UnicodeString inputString(charString.elems(), inputLength); |
| UNormalizationMode norm_mode = UNORM_NFKC; |
| UBool isNormalized = |
| Normalizer::quickCheck(inputString, norm_mode, status) == UNORM_YES || |
| Normalizer::isNormalized(inputString, norm_mode, status); |
| |
| AutoBuffer<int32_t, defaultInputLength> charPositions(inputLength + 1); |
| int numChars = 0; |
| UText normalizedText = UTEXT_INITIALIZER; |
| // Needs to be declared here because normalizedText holds onto its buffer. |
| UnicodeString normalizedString; |
| if (isNormalized) { |
| int32_t index = 0; |
| charPositions[0] = 0; |
| while(index < inputString.length()) { |
| index = inputString.moveIndex32(index, 1); |
| charPositions[++numChars] = index; |
| } |
| utext_openUnicodeString(&normalizedText, &inputString, &status); |
| } |
| else { |
| Normalizer::normalize(inputString, norm_mode, 0, normalizedString, status); |
| if (U_FAILURE(status)) |
| return 0; |
| charPositions.resize(normalizedString.length() + 1); |
| Normalizer normalizer(charString.elems(), inputLength, norm_mode); |
| int32_t index = 0; |
| charPositions[0] = 0; |
| while(index < normalizer.endIndex()){ |
| UChar32 uc = normalizer.next(); |
| charPositions[++numChars] = index = normalizer.getIndex(); |
| } |
| utext_openUnicodeString(&normalizedText, &normalizedString, &status); |
| } |
| |
| if (U_FAILURE(status)) |
| return 0; |
| |
| // From this point on, all the indices refer to the indices of |
| // the normalized input string. |
| |
| // bestSnlp[i] is the snlp of the best segmentation of the first i |
| // characters in the range to be matched. |
| AutoBuffer<uint32_t, defaultInputLength> bestSnlp(numChars + 1); |
| bestSnlp[0] = 0; |
| for(int i=1; i<=numChars; i++){ |
| bestSnlp[i] = kuint32max; |
| } |
| |
| // prev[i] is the index of the last CJK character in the previous word in |
| // the best segmentation of the first i characters. |
| AutoBuffer<int, defaultInputLength> prev(numChars + 1); |
| for(int i=0; i<=numChars; i++){ |
| prev[i] = -1; |
| } |
| |
| const size_t maxWordSize = 20; |
| AutoBuffer<uint16_t, maxWordSize> values(numChars); |
| AutoBuffer<int32_t, maxWordSize> lengths(numChars); |
| |
| // Dynamic programming to find the best segmentation. |
| bool is_prev_katakana = false; |
| for (int i = 0; i < numChars; ++i) { |
| //utext_setNativeIndex(text, rangeStart + i); |
| utext_setNativeIndex(&normalizedText, i); |
| if (bestSnlp[i] == kuint32max) |
| continue; |
| |
| int count; |
| // limit maximum word length matched to size of current substring |
| int maxSearchLength = (i + maxWordSize < (size_t) numChars)? maxWordSize: numChars - i; |
| |
| fDictionary->matches(&normalizedText, maxSearchLength, lengths.elems(), count, maxSearchLength, values.elems()); |
| |
| // if there are no single character matches found in the dictionary |
| // starting with this charcter, treat character as a 1-character word |
| // with the highest value possible, i.e. the least likely to occur. |
| // Exclude Korean characters from this treatment, as they should be left |
| // together by default. |
| if((count == 0 || lengths[0] != 1) && |
| !fHangulWordSet.contains(utext_current32(&normalizedText))){ |
| values[count] = maxSnlp; |
| lengths[count++] = 1; |
| } |
| |
| for (int j = 0; j < count; j++){ |
| //U_ASSERT(values[j] >= 0 && values[j] <= maxSnlp); |
| uint32_t newSnlp = bestSnlp[i] + values[j]; |
| if (newSnlp < bestSnlp[lengths[j] + i]) { |
| bestSnlp[lengths[j] + i] = newSnlp; |
| prev[lengths[j] + i] = i; |
| } |
| } |
| |
| // In Japanese, |
| // Katakana word in single character is pretty rare. So we apply |
| // the following heuristic to Katakana: any continuous run of Katakana |
| // characters is considered a candidate word with a default cost |
| // specified in the katakanaCost table according to its length. |
| //utext_setNativeIndex(text, rangeStart + i); |
| utext_setNativeIndex(&normalizedText, i); |
| bool is_katakana = isKatakana(utext_current32(&normalizedText)); |
| if (!is_prev_katakana && is_katakana) { |
| int j = i + 1; |
| utext_next32(&normalizedText); |
| // Find the end of the continuous run of Katakana characters |
| while (j < numChars && (j - i) < kMaxKatakanaGroupLength && |
| isKatakana(utext_current32(&normalizedText))) { |
| utext_next32(&normalizedText); |
| ++j; |
| } |
| if ((j - i) < kMaxKatakanaGroupLength) { |
| uint32_t newSnlp = bestSnlp[i] + getKatakanaCost(j - i); |
| if (newSnlp < bestSnlp[j]) { |
| bestSnlp[j] = newSnlp; |
| prev[j] = i; |
| } |
| } |
| } |
| is_prev_katakana = is_katakana; |
| } |
| |
| // Start pushing the optimal offset index into t_boundary (t for tentative). |
| // prev[numChars] is guaranteed to be meaningful. |
| // We'll first push in the reverse order, i.e., |
| // t_boundary[0] = numChars, and afterwards do a swap. |
| AutoBuffer<int, maxWordSize> t_boundary(numChars + 1); |
| |
| int numBreaks = 0; |
| // No segmentation found, set boundary to end of range |
| if (bestSnlp[numChars] == kuint32max) { |
| t_boundary[numBreaks++] = numChars; |
| } else { |
| for (int i = numChars; i > 0; i = prev[i]){ |
| t_boundary[numBreaks++] = i; |
| |
| } |
| U_ASSERT(prev[t_boundary[numBreaks-1]] == 0); |
| } |
| |
| // Reverse offset index in t_boundary. |
| // Don't add a break for the start of the dictionary range if there is one |
| // there already. |
| if (foundBreaks.size() == 0 || foundBreaks.peeki() < rangeStart) { |
| t_boundary[numBreaks++] = 0; |
| } |
| |
| // Now that we're done, convert positions in t_bdry[] (indices in |
| // the normalized input string) back to indices in the raw input string |
| // while reversing t_bdry and pushing values to foundBreaks. |
| for (int i = numBreaks-1; i >= 0; i--) { |
| foundBreaks.push(charPositions[t_boundary[i]] + rangeStart, status); |
| } |
| |
| utext_close(&normalizedText); |
| return numBreaks; |
| } |
| |
| U_NAMESPACE_END |
| |
| #endif /* #if !UCONFIG_NO_BREAK_ITERATION */ |