1 // © 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ********************************************************************** 5 * Copyright (c) 2001-2007, International Business Machines 6 * Corporation and others. All Rights Reserved. 7 ********************************************************************** 8 * Date Name Description 9 * 11/20/2001 aliu Creation. 10 ********************************************************************** 11 */ 12 #ifndef ESCTRN_H 13 #define ESCTRN_H 14 15 #include "unicode/utypes.h" 16 17 #if !UCONFIG_NO_TRANSLITERATION 18 19 #include "unicode/translit.h" 20 21 U_NAMESPACE_BEGIN 22 23 /** 24 * A transliterator that converts Unicode characters to an escape 25 * form. Examples of escape forms are "U+4E01" and "". 26 * Escape forms have a prefix and suffix, either of which may be 27 * empty, a radix, typically 16 or 10, a minimum digit count, 28 * typically 1, 4, or 8, and a boolean that specifies whether 29 * supplemental characters are handled as 32-bit code points or as two 30 * 16-bit code units. Most escape forms handle 32-bit code points, 31 * but some, such as the Java form, intentionally break them into two 32 * surrogate pairs, for backward compatibility. 33 * 34 * <p>Some escape forms actually have two different patterns, one for 35 * BMP characters (0..FFFF) and one for supplements (>FFFF). To 36 * handle this, a second EscapeTransliterator may be defined that 37 * specifies the pattern to be produced for supplementals. An example 38 * of a form that requires this is the C form, which uses "\\uFFFF" 39 * for BMP characters and "\\U0010FFFF" for supplementals. 40 * 41 * <p>This class is package private. It registers several standard 42 * variants with the system which are then accessed via their IDs. 43 * 44 * @author Alan Liu 45 */ 46 class EscapeTransliterator : public Transliterator { 47 48 private: 49 50 /** 51 * The prefix of the escape form; may be empty, but usually isn't. 52 */ 53 UnicodeString prefix; 54 55 /** 56 * The prefix of the escape form; often empty. 57 */ 58 UnicodeString suffix; 59 60 /** 61 * The radix to display the number in. Typically 16 or 10. Must 62 * be in the range 2 to 36. 63 */ 64 int32_t radix; 65 66 /** 67 * The minimum number of digits. Typically 1, 4, or 8. Values 68 * less than 1 are equivalent to 1. 69 */ 70 int32_t minDigits; 71 72 /** 73 * If true, supplementals are handled as 32-bit code points. If 74 * false, they are handled as two 16-bit code units. 75 */ 76 UBool grokSupplementals; 77 78 /** 79 * The form to be used for supplementals. If this is null then 80 * the same form is used for BMP characters and supplementals. If 81 * this is not null and if grokSupplementals is true then the 82 * prefix, suffix, radix, and minDigits of this object are used 83 * for supplementals. This pointer is owned. 84 */ 85 EscapeTransliterator* supplementalHandler; 86 87 public: 88 89 /** 90 * Registers standard variants with the system. Called by 91 * Transliterator during initialization. 92 */ 93 static void registerIDs(); 94 95 /** 96 * Constructs an escape transliterator with the given ID and 97 * parameters. See the class member documentation for details. 98 */ 99 EscapeTransliterator(const UnicodeString& ID, 100 const UnicodeString& prefix, const UnicodeString& suffix, 101 int32_t radix, int32_t minDigits, 102 UBool grokSupplementals, 103 EscapeTransliterator* adoptedSupplementalHandler); 104 105 /** 106 * Copy constructor. 107 */ 108 EscapeTransliterator(const EscapeTransliterator&); 109 110 /** 111 * Destructor. 112 */ 113 virtual ~EscapeTransliterator(); 114 115 /** 116 * Transliterator API. 117 */ 118 virtual Transliterator* clone() const; 119 120 /** 121 * ICU "poor man's RTTI", returns a UClassID for the actual class. 122 */ 123 virtual UClassID getDynamicClassID() const; 124 125 /** 126 * ICU "poor man's RTTI", returns a UClassID for this class. 127 */ 128 U_I18N_API static UClassID U_EXPORT2 getStaticClassID(); 129 130 protected: 131 132 /** 133 * Implements {@link Transliterator#handleTransliterate}. 134 */ 135 virtual void handleTransliterate(Replaceable& text, UTransPosition& offset, 136 UBool isIncremental) const; 137 138 }; 139 140 U_NAMESPACE_END 141 142 #endif /* #if !UCONFIG_NO_TRANSLITERATION */ 143 144 #endif 145