1 /* 2 ********************************************************************** 3 * Copyright (c) 2001-2004, International Business Machines 4 * Corporation and others. All Rights Reserved. 5 ********************************************************************** 6 * Date Name Description 7 * 07/18/01 aliu Creation. 8 ********************************************************************** 9 */ 10 11 #include "unicode/unifilt.h" 12 #include "unicode/rep.h" 13 14 U_NAMESPACE_BEGIN 15 UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(UnicodeFilter) 16 17 18 /* Define this here due to the lack of another file. 19 It can't be defined in the header */ 20 UnicodeMatcher::~UnicodeMatcher() {} 21 22 UnicodeFilter::~UnicodeFilter() {} 23 24 /** 25 * UnicodeFunctor API. Cast 'this' to a UnicodeMatcher* pointer 26 * and return the pointer. 27 */ 28 UnicodeMatcher* UnicodeFilter::toMatcher() const { 29 return (UnicodeMatcher*) this; 30 } 31 32 void UnicodeFilter::setData(const TransliterationRuleData*) {} 33 34 /** 35 * Default implementation of UnicodeMatcher::matches() for Unicode 36 * filters. Matches a single code point at offset (either one or 37 * two 16-bit code units). 38 */ 39 UMatchDegree UnicodeFilter::matches(const Replaceable& text, 40 int32_t& offset, 41 int32_t limit, 42 UBool incremental) { 43 UChar32 c; 44 if (offset < limit && 45 contains(c = text.char32At(offset))) { 46 offset += UTF_CHAR_LENGTH(c); 47 return U_MATCH; 48 } 49 if (offset > limit && 50 contains(c = text.char32At(offset))) { 51 // Backup offset by 1, unless the preceding character is a 52 // surrogate pair -- then backup by 2 (keep offset pointing at 53 // the lead surrogate). 54 --offset; 55 if (offset >= 0) { 56 offset -= UTF_CHAR_LENGTH(text.char32At(offset)) - 1; 57 } 58 return U_MATCH; 59 } 60 if (incremental && offset == limit) { 61 return U_PARTIAL_MATCH; 62 } 63 return U_MISMATCH; 64 } 65 66 U_NAMESPACE_END 67 68 //eof 69
