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Diffstat (limited to 'intl/icu/source/common/unicode/unifilt.h')
| -rw-r--r-- | intl/icu/source/common/unicode/unifilt.h | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/intl/icu/source/common/unicode/unifilt.h b/intl/icu/source/common/unicode/unifilt.h new file mode 100644 index 000000000..0fdcd1482 --- /dev/null +++ b/intl/icu/source/common/unicode/unifilt.h @@ -0,0 +1,122 @@ +// Copyright (C) 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +********************************************************************** +* Copyright (C) 1999-2010, International Business Machines Corporation and others. +* All Rights Reserved. +********************************************************************** +* Date Name Description +* 11/17/99 aliu Creation. +********************************************************************** +*/ +#ifndef UNIFILT_H +#define UNIFILT_H + +#include "unicode/unifunct.h" +#include "unicode/unimatch.h" + +/** + * \file + * \brief C++ API: Unicode Filter + */ + +U_NAMESPACE_BEGIN + +/** + * U_ETHER is used to represent character values for positions outside + * a range. For example, transliterator uses this to represent + * characters outside the range contextStart..contextLimit-1. This + * allows explicit matching by rules and UnicodeSets of text outside a + * defined range. + * @stable ICU 3.0 + */ +#define U_ETHER ((UChar)0xFFFF) + +/** + * + * <code>UnicodeFilter</code> defines a protocol for selecting a + * subset of the full range (U+0000 to U+10FFFF) of Unicode characters. + * Currently, filters are used in conjunction with classes like {@link + * Transliterator} to only process selected characters through a + * transformation. + * + * <p>Note: UnicodeFilter currently stubs out two pure virtual methods + * of its base class, UnicodeMatcher. These methods are toPattern() + * and matchesIndexValue(). This is done so that filter classes that + * are not actually used as matchers -- specifically, those in the + * UnicodeFilterLogic component, and those in tests -- can continue to + * work without defining these methods. As long as a filter is not + * used in an RBT during real transliteration, these methods will not + * be called. However, this breaks the UnicodeMatcher base class + * protocol, and it is not a correct solution. + * + * <p>In the future we may revisit the UnicodeMatcher / UnicodeFilter + * hierarchy and either redesign it, or simply remove the stubs in + * UnicodeFilter and force subclasses to implement the full + * UnicodeMatcher protocol. + * + * @see UnicodeFilterLogic + * @stable ICU 2.0 + */ +class U_COMMON_API UnicodeFilter : public UnicodeFunctor, public UnicodeMatcher { + +public: + /** + * Destructor + * @stable ICU 2.0 + */ + virtual ~UnicodeFilter(); + + /** + * Returns <tt>true</tt> for characters that are in the selected + * subset. In other words, if a character is <b>to be + * filtered</b>, then <tt>contains()</tt> returns + * <b><tt>false</tt></b>. + * @stable ICU 2.0 + */ + virtual UBool contains(UChar32 c) const = 0; + + /** + * UnicodeFunctor API. Cast 'this' to a UnicodeMatcher* pointer + * and return the pointer. + * @stable ICU 2.4 + */ + virtual UnicodeMatcher* toMatcher() const; + + /** + * Implement UnicodeMatcher API. + * @stable ICU 2.4 + */ + virtual UMatchDegree matches(const Replaceable& text, + int32_t& offset, + int32_t limit, + UBool incremental); + + /** + * UnicodeFunctor API. Nothing to do. + * @stable ICU 2.4 + */ + virtual void setData(const TransliterationRuleData*); + + /** + * ICU "poor man's RTTI", returns a UClassID for this class. + * + * @stable ICU 2.2 + */ + static UClassID U_EXPORT2 getStaticClassID(); + +protected: + + /* + * Since this class has pure virtual functions, + * a constructor can't be used. + * @stable ICU 2.0 + */ +/* UnicodeFilter();*/ +}; + +/*inline UnicodeFilter::UnicodeFilter() {}*/ + +U_NAMESPACE_END + +#endif |