Victor Chang | 7322950 | 2020-09-17 13:39:19 +0100 | [diff] [blame] | 1 | // © 2016 and later: Unicode, Inc. and others. |
| 2 | // License & terms of use: http://www.unicode.org/copyright.html |
| 3 | /* |
| 4 | ********************************************************************** |
| 5 | * Copyright (C) 1999-2007, International Business Machines Corporation |
| 6 | * and others. All Rights Reserved. |
| 7 | ********************************************************************** |
| 8 | * Date Name Description |
| 9 | * 11/17/99 aliu Creation. |
| 10 | ********************************************************************** |
| 11 | */ |
| 12 | #ifndef RBT_SET_H |
| 13 | #define RBT_SET_H |
| 14 | |
| 15 | #include "unicode/utypes.h" |
| 16 | |
| 17 | #if !UCONFIG_NO_TRANSLITERATION |
| 18 | |
| 19 | #include "unicode/uobject.h" |
| 20 | #include "unicode/utrans.h" |
| 21 | #include "uvector.h" |
| 22 | |
| 23 | U_NAMESPACE_BEGIN |
| 24 | |
| 25 | class Replaceable; |
| 26 | class TransliterationRule; |
| 27 | class TransliterationRuleData; |
| 28 | class UnicodeFilter; |
| 29 | class UnicodeString; |
| 30 | class UnicodeSet; |
| 31 | |
| 32 | /** |
| 33 | * A set of rules for a <code>RuleBasedTransliterator</code>. |
| 34 | * @author Alan Liu |
| 35 | */ |
| 36 | class TransliterationRuleSet : public UMemory { |
| 37 | /** |
| 38 | * Vector of rules, in the order added. This is used while the |
| 39 | * rule set is getting built. After that, freeze() reorders and |
| 40 | * indexes the rules into rules[]. Any given rule is stored once |
| 41 | * in ruleVector, and one or more times in rules[]. ruleVector |
| 42 | * owns and deletes the rules. |
| 43 | */ |
| 44 | UVector* ruleVector; |
| 45 | |
| 46 | /** |
| 47 | * Sorted and indexed table of rules. This is created by freeze() |
| 48 | * from the rules in ruleVector. It contains alias pointers to |
| 49 | * the rules in ruleVector. It is zero before freeze() is called |
| 50 | * and non-zero thereafter. |
| 51 | */ |
| 52 | TransliterationRule** rules; |
| 53 | |
| 54 | /** |
| 55 | * Index table. For text having a first character c, compute x = c&0xFF. |
| 56 | * Now use rules[index[x]..index[x+1]-1]. This index table is created by |
| 57 | * freeze(). Before freeze() is called it contains garbage. |
| 58 | */ |
| 59 | int32_t index[257]; |
| 60 | |
| 61 | /** |
| 62 | * Length of the longest preceding context |
| 63 | */ |
| 64 | int32_t maxContextLength; |
| 65 | |
| 66 | public: |
| 67 | |
| 68 | /** |
| 69 | * Construct a new empty rule set. |
| 70 | * @param status Output parameter filled in with success or failure status. |
| 71 | */ |
| 72 | TransliterationRuleSet(UErrorCode& status); |
| 73 | |
| 74 | /** |
| 75 | * Copy constructor. |
| 76 | */ |
| 77 | TransliterationRuleSet(const TransliterationRuleSet&); |
| 78 | |
| 79 | /** |
| 80 | * Destructor. |
| 81 | */ |
| 82 | virtual ~TransliterationRuleSet(); |
| 83 | |
| 84 | /** |
| 85 | * Change the data object that this rule belongs to. Used |
| 86 | * internally by the TransliterationRuleData copy constructor. |
| 87 | * @param data the new data value to be set. |
| 88 | */ |
| 89 | void setData(const TransliterationRuleData* data); |
| 90 | |
| 91 | /** |
| 92 | * Return the maximum context length. |
| 93 | * @return the length of the longest preceding context. |
| 94 | */ |
| 95 | virtual int32_t getMaximumContextLength(void) const; |
| 96 | |
| 97 | /** |
| 98 | * Add a rule to this set. Rules are added in order, and order is |
| 99 | * significant. The last call to this method must be followed by |
| 100 | * a call to <code>freeze()</code> before the rule set is used. |
| 101 | * This method must <em>not</em> be called after freeze() has been |
| 102 | * called. |
| 103 | * |
| 104 | * @param adoptedRule the rule to add |
| 105 | */ |
| 106 | virtual void addRule(TransliterationRule* adoptedRule, |
| 107 | UErrorCode& status); |
| 108 | |
| 109 | /** |
| 110 | * Check this for masked rules and index it to optimize performance. |
| 111 | * The sequence of operations is: (1) add rules to a set using |
| 112 | * <code>addRule()</code>; (2) freeze the set using |
| 113 | * <code>freeze()</code>; (3) use the rule set. If |
| 114 | * <code>addRule()</code> is called after calling this method, it |
| 115 | * invalidates this object, and this method must be called again. |
| 116 | * That is, <code>freeze()</code> may be called multiple times, |
| 117 | * although for optimal performance it shouldn't be. |
| 118 | * @param parseError A pointer to UParseError to receive information about errors |
| 119 | * occurred. |
| 120 | * @param status Output parameter filled in with success or failure status. |
| 121 | */ |
| 122 | virtual void freeze(UParseError& parseError, UErrorCode& status); |
| 123 | |
| 124 | /** |
| 125 | * Transliterate the given text with the given UTransPosition |
Victor Chang | ce4bf3c | 2021-01-19 16:34:24 +0000 | [diff] [blame] | 126 | * indices. Return true if the transliteration should continue |
| 127 | * or false if it should halt (because of a U_PARTIAL_MATCH match). |
| 128 | * Note that false is only ever returned if isIncremental is true. |
Victor Chang | 7322950 | 2020-09-17 13:39:19 +0100 | [diff] [blame] | 129 | * @param text the text to be transliterated |
| 130 | * @param index the position indices, which will be updated |
Victor Chang | ce4bf3c | 2021-01-19 16:34:24 +0000 | [diff] [blame] | 131 | * @param isIncremental if true, assume new text may be inserted |
| 132 | * at index.limit, and return false if thre is a partial match. |
| 133 | * @return true unless a U_PARTIAL_MATCH has been obtained, |
Victor Chang | 7322950 | 2020-09-17 13:39:19 +0100 | [diff] [blame] | 134 | * indicating that transliteration should stop until more text |
| 135 | * arrives. |
| 136 | */ |
| 137 | UBool transliterate(Replaceable& text, |
| 138 | UTransPosition& index, |
| 139 | UBool isIncremental); |
| 140 | |
| 141 | /** |
| 142 | * Create rule strings that represents this rule set. |
| 143 | * @param result string to receive the rule strings. Current |
| 144 | * contents will be deleted. |
| 145 | * @param escapeUnprintable True, will escape the unprintable characters |
| 146 | * @return A reference to 'result'. |
| 147 | */ |
| 148 | virtual UnicodeString& toRules(UnicodeString& result, |
| 149 | UBool escapeUnprintable) const; |
| 150 | |
| 151 | /** |
| 152 | * Return the set of all characters that may be modified |
| 153 | * (getTarget=false) or emitted (getTarget=true) by this set. |
| 154 | */ |
| 155 | UnicodeSet& getSourceTargetSet(UnicodeSet& result, |
| 156 | UBool getTarget) const; |
| 157 | |
| 158 | private: |
| 159 | |
| 160 | TransliterationRuleSet &operator=(const TransliterationRuleSet &other); // forbid copying of this class |
| 161 | }; |
| 162 | |
| 163 | U_NAMESPACE_END |
| 164 | |
| 165 | #endif /* #if !UCONFIG_NO_TRANSLITERATION */ |
| 166 | |
| 167 | #endif |