1 | // © 2016 and later: Unicode, Inc. and others. |
2 | // License & terms of use: http://www.unicode.org/copyright.html |
3 | /* |
4 | ******************************************************************************* |
5 | * Copyright (C) 2010-2016, International Business Machines |
6 | * Corporation and others. All Rights Reserved. |
7 | ******************************************************************************* |
8 | * file name: bytestriebuilder.h |
9 | * encoding: UTF-8 |
10 | * tab size: 8 (not used) |
11 | * indentation:4 |
12 | * |
13 | * created on: 2010sep25 |
14 | * created by: Markus W. Scherer |
15 | */ |
16 | |
17 | /** |
18 | * \file |
19 | * \brief C++ API: Builder for icu::BytesTrie |
20 | */ |
21 | |
22 | #ifndef __BYTESTRIEBUILDER_H__ |
23 | #define __BYTESTRIEBUILDER_H__ |
24 | |
25 | #include "unicode/utypes.h" |
26 | |
27 | #if U_SHOW_CPLUSPLUS_API |
28 | |
29 | #include "unicode/bytestrie.h" |
30 | #include "unicode/stringpiece.h" |
31 | #include "unicode/stringtriebuilder.h" |
32 | |
33 | class BytesTrieTest; |
34 | |
35 | U_NAMESPACE_BEGIN |
36 | |
37 | class BytesTrieElement; |
38 | class CharString; |
39 | /** |
40 | * Builder class for BytesTrie. |
41 | * |
42 | * This class is not intended for public subclassing. |
43 | * @stable ICU 4.8 |
44 | */ |
45 | class U_COMMON_API BytesTrieBuilder : public StringTrieBuilder { |
46 | public: |
47 | /** |
48 | * Constructs an empty builder. |
49 | * @param errorCode Standard ICU error code. |
50 | * @stable ICU 4.8 |
51 | */ |
52 | BytesTrieBuilder(UErrorCode &errorCode); |
53 | |
54 | /** |
55 | * Destructor. |
56 | * @stable ICU 4.8 |
57 | */ |
58 | virtual ~BytesTrieBuilder(); |
59 | |
60 | /** |
61 | * Adds a (byte sequence, value) pair. |
62 | * The byte sequence must be unique. |
63 | * The bytes will be copied; the builder does not keep |
64 | * a reference to the input StringPiece or its data(). |
65 | * @param s The input byte sequence. |
66 | * @param value The value associated with this byte sequence. |
67 | * @param errorCode Standard ICU error code. Its input value must |
68 | * pass the U_SUCCESS() test, or else the function returns |
69 | * immediately. Check for U_FAILURE() on output or use with |
70 | * function chaining. (See User Guide for details.) |
71 | * @return *this |
72 | * @stable ICU 4.8 |
73 | */ |
74 | BytesTrieBuilder &add(StringPiece s, int32_t value, UErrorCode &errorCode); |
75 | |
76 | /** |
77 | * Builds a BytesTrie for the add()ed data. |
78 | * Once built, no further data can be add()ed until clear() is called. |
79 | * |
80 | * A BytesTrie cannot be empty. At least one (byte sequence, value) pair |
81 | * must have been add()ed. |
82 | * |
83 | * This method passes ownership of the builder's internal result array to the new trie object. |
84 | * Another call to any build() variant will re-serialize the trie. |
85 | * After clear() has been called, a new array will be used as well. |
86 | * @param buildOption Build option, see UStringTrieBuildOption. |
87 | * @param errorCode Standard ICU error code. Its input value must |
88 | * pass the U_SUCCESS() test, or else the function returns |
89 | * immediately. Check for U_FAILURE() on output or use with |
90 | * function chaining. (See User Guide for details.) |
91 | * @return A new BytesTrie for the add()ed data. |
92 | * @stable ICU 4.8 |
93 | */ |
94 | BytesTrie *build(UStringTrieBuildOption buildOption, UErrorCode &errorCode); |
95 | |
96 | /** |
97 | * Builds a BytesTrie for the add()ed data and byte-serializes it. |
98 | * Once built, no further data can be add()ed until clear() is called. |
99 | * |
100 | * A BytesTrie cannot be empty. At least one (byte sequence, value) pair |
101 | * must have been add()ed. |
102 | * |
103 | * Multiple calls to buildStringPiece() return StringPieces referring to the |
104 | * builder's same byte array, without rebuilding. |
105 | * If buildStringPiece() is called after build(), the trie will be |
106 | * re-serialized into a new array (because build() passes on ownership). |
107 | * If build() is called after buildStringPiece(), the trie object returned |
108 | * by build() will become the owner of the underlying string for the |
109 | * previously returned StringPiece. |
110 | * After clear() has been called, a new array will be used as well. |
111 | * @param buildOption Build option, see UStringTrieBuildOption. |
112 | * @param errorCode Standard ICU error code. Its input value must |
113 | * pass the U_SUCCESS() test, or else the function returns |
114 | * immediately. Check for U_FAILURE() on output or use with |
115 | * function chaining. (See User Guide for details.) |
116 | * @return A StringPiece which refers to the byte-serialized BytesTrie for the add()ed data. |
117 | * @stable ICU 4.8 |
118 | */ |
119 | StringPiece buildStringPiece(UStringTrieBuildOption buildOption, UErrorCode &errorCode); |
120 | |
121 | /** |
122 | * Removes all (byte sequence, value) pairs. |
123 | * New data can then be add()ed and a new trie can be built. |
124 | * @return *this |
125 | * @stable ICU 4.8 |
126 | */ |
127 | BytesTrieBuilder &clear(); |
128 | |
129 | private: |
130 | friend class ::BytesTrieTest; |
131 | |
132 | BytesTrieBuilder(const BytesTrieBuilder &other) = delete; // no copy constructor |
133 | BytesTrieBuilder &operator=(const BytesTrieBuilder &other) = delete; // no assignment operator |
134 | |
135 | void buildBytes(UStringTrieBuildOption buildOption, UErrorCode &errorCode); |
136 | |
137 | virtual int32_t getElementStringLength(int32_t i) const override; |
138 | virtual char16_t getElementUnit(int32_t i, int32_t byteIndex) const override; |
139 | virtual int32_t getElementValue(int32_t i) const override; |
140 | |
141 | virtual int32_t getLimitOfLinearMatch(int32_t first, int32_t last, int32_t byteIndex) const override; |
142 | |
143 | virtual int32_t countElementUnits(int32_t start, int32_t limit, int32_t byteIndex) const override; |
144 | virtual int32_t skipElementsBySomeUnits(int32_t i, int32_t byteIndex, int32_t count) const override; |
145 | virtual int32_t indexOfElementWithNextUnit(int32_t i, int32_t byteIndex, char16_t byte) const override; |
146 | |
147 | virtual UBool matchNodesCanHaveValues() const override { return false; } |
148 | |
149 | virtual int32_t getMaxBranchLinearSubNodeLength() const override { return BytesTrie::kMaxBranchLinearSubNodeLength; } |
150 | virtual int32_t getMinLinearMatch() const override { return BytesTrie::kMinLinearMatch; } |
151 | virtual int32_t getMaxLinearMatchLength() const override { return BytesTrie::kMaxLinearMatchLength; } |
152 | |
153 | /** |
154 | * @internal (private) |
155 | */ |
156 | class BTLinearMatchNode : public LinearMatchNode { |
157 | public: |
158 | BTLinearMatchNode(const char *units, int32_t len, Node *nextNode); |
159 | virtual bool operator==(const Node &other) const override; |
160 | virtual void write(StringTrieBuilder &builder) override; |
161 | private: |
162 | const char *s; |
163 | }; |
164 | |
165 | virtual Node *createLinearMatchNode(int32_t i, int32_t byteIndex, int32_t length, |
166 | Node *nextNode) const override; |
167 | |
168 | UBool ensureCapacity(int32_t length); |
169 | virtual int32_t write(int32_t byte) override; |
170 | int32_t write(const char *b, int32_t length); |
171 | virtual int32_t writeElementUnits(int32_t i, int32_t byteIndex, int32_t length) override; |
172 | virtual int32_t writeValueAndFinal(int32_t i, UBool isFinal) override; |
173 | virtual int32_t writeValueAndType(UBool hasValue, int32_t value, int32_t node) override; |
174 | virtual int32_t writeDeltaTo(int32_t jumpTarget) override; |
175 | static int32_t internalEncodeDelta(int32_t i, char intBytes[]); |
176 | |
177 | CharString *strings; // Pointer not object so we need not #include internal charstr.h. |
178 | BytesTrieElement *elements; |
179 | int32_t elementsCapacity; |
180 | int32_t elementsLength; |
181 | |
182 | // Byte serialization of the trie. |
183 | // Grows from the back: bytesLength measures from the end of the buffer! |
184 | char *bytes; |
185 | int32_t bytesCapacity; |
186 | int32_t bytesLength; |
187 | }; |
188 | |
189 | U_NAMESPACE_END |
190 | |
191 | #endif /* U_SHOW_CPLUSPLUS_API */ |
192 | |
193 | #endif // __BYTESTRIEBUILDER_H__ |
194 | |