1/*
2*******************************************************************************
3*   Copyright (C) 2010-2013, International Business Machines
4*   Corporation and others.  All Rights Reserved.
5*******************************************************************************
6*   file name:  ucharstriebuilder.h
7*   encoding:   US-ASCII
8*   tab size:   8 (not used)
9*   indentation:4
10*
11*   created on: 2010nov14
12*   created by: Markus W. Scherer
13*/
14
15#ifndef __UCHARSTRIEBUILDER_H__
16#define __UCHARSTRIEBUILDER_H__
17
18#include "unicode/utypes.h"
19#include "unicode/stringtriebuilder.h"
20#include "unicode/ucharstrie.h"
21#include "unicode/unistr.h"
22
23/**
24 * \file
25 * \brief C++ API: Builder for icu::UCharsTrie
26 */
27
28U_NAMESPACE_BEGIN
29
30class UCharsTrieElement;
31
32/**
33 * Builder class for UCharsTrie.
34 *
35 * This class is not intended for public subclassing.
36 * @stable ICU 4.8
37 */
38class U_COMMON_API UCharsTrieBuilder : public StringTrieBuilder {
39public:
40    /**
41     * Constructs an empty builder.
42     * @param errorCode Standard ICU error code.
43     * @stable ICU 4.8
44     */
45    UCharsTrieBuilder(UErrorCode &errorCode);
46
47    /**
48     * Destructor.
49     * @stable ICU 4.8
50     */
51    virtual ~UCharsTrieBuilder();
52
53    /**
54     * Adds a (string, value) pair.
55     * The string must be unique.
56     * The string contents will be copied; the builder does not keep
57     * a reference to the input UnicodeString or its buffer.
58     * @param s The input string.
59     * @param value The value associated with this string.
60     * @param errorCode Standard ICU error code. Its input value must
61     *                  pass the U_SUCCESS() test, or else the function returns
62     *                  immediately. Check for U_FAILURE() on output or use with
63     *                  function chaining. (See User Guide for details.)
64     * @return *this
65     * @stable ICU 4.8
66     */
67    UCharsTrieBuilder &add(const UnicodeString &s, int32_t value, UErrorCode &errorCode);
68
69    /**
70     * Builds a UCharsTrie for the add()ed data.
71     * Once built, no further data can be add()ed until clear() is called.
72     *
73     * A UCharsTrie cannot be empty. At least one (string, value) pair
74     * must have been add()ed.
75     *
76     * This method passes ownership of the builder's internal result array to the new trie object.
77     * Another call to any build() variant will re-serialize the trie.
78     * After clear() has been called, a new array will be used as well.
79     * @param buildOption Build option, see UStringTrieBuildOption.
80     * @param errorCode Standard ICU error code. Its input value must
81     *                  pass the U_SUCCESS() test, or else the function returns
82     *                  immediately. Check for U_FAILURE() on output or use with
83     *                  function chaining. (See User Guide for details.)
84     * @return A new UCharsTrie for the add()ed data.
85     * @stable ICU 4.8
86     */
87    UCharsTrie *build(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
88
89    /**
90     * Builds a UCharsTrie for the add()ed data and UChar-serializes it.
91     * Once built, no further data can be add()ed until clear() is called.
92     *
93     * A UCharsTrie cannot be empty. At least one (string, value) pair
94     * must have been add()ed.
95     *
96     * Multiple calls to buildUnicodeString() set the UnicodeStrings to the
97     * builder's same UChar array, without rebuilding.
98     * If buildUnicodeString() is called after build(), the trie will be
99     * re-serialized into a new array.
100     * If build() is called after buildUnicodeString(), the trie object will become
101     * the owner of the previously returned array.
102     * After clear() has been called, a new array will be used as well.
103     * @param buildOption Build option, see UStringTrieBuildOption.
104     * @param result A UnicodeString which will be set to the UChar-serialized
105     *               UCharsTrie for the add()ed data.
106     * @param errorCode Standard ICU error code. Its input value must
107     *                  pass the U_SUCCESS() test, or else the function returns
108     *                  immediately. Check for U_FAILURE() on output or use with
109     *                  function chaining. (See User Guide for details.)
110     * @return result
111     * @stable ICU 4.8
112     */
113    UnicodeString &buildUnicodeString(UStringTrieBuildOption buildOption, UnicodeString &result,
114                                      UErrorCode &errorCode);
115
116    /**
117     * Removes all (string, value) pairs.
118     * New data can then be add()ed and a new trie can be built.
119     * @return *this
120     * @stable ICU 4.8
121     */
122    UCharsTrieBuilder &clear() {
123        strings.remove();
124        elementsLength=0;
125        ucharsLength=0;
126        return *this;
127    }
128
129private:
130    UCharsTrieBuilder(const UCharsTrieBuilder &other);  // no copy constructor
131    UCharsTrieBuilder &operator=(const UCharsTrieBuilder &other);  // no assignment operator
132
133    void buildUChars(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
134
135    virtual int32_t getElementStringLength(int32_t i) const;
136    virtual UChar getElementUnit(int32_t i, int32_t unitIndex) const;
137    virtual int32_t getElementValue(int32_t i) const;
138
139    virtual int32_t getLimitOfLinearMatch(int32_t first, int32_t last, int32_t unitIndex) const;
140
141    virtual int32_t countElementUnits(int32_t start, int32_t limit, int32_t unitIndex) const;
142    virtual int32_t skipElementsBySomeUnits(int32_t i, int32_t unitIndex, int32_t count) const;
143    virtual int32_t indexOfElementWithNextUnit(int32_t i, int32_t unitIndex, UChar unit) const;
144
145    virtual UBool matchNodesCanHaveValues() const { return TRUE; }
146
147    virtual int32_t getMaxBranchLinearSubNodeLength() const { return UCharsTrie::kMaxBranchLinearSubNodeLength; }
148    virtual int32_t getMinLinearMatch() const { return UCharsTrie::kMinLinearMatch; }
149    virtual int32_t getMaxLinearMatchLength() const { return UCharsTrie::kMaxLinearMatchLength; }
150
151#ifndef U_HIDE_INTERNAL_API
152    class UCTLinearMatchNode : public LinearMatchNode {
153    public:
154        UCTLinearMatchNode(const UChar *units, int32_t len, Node *nextNode);
155        virtual UBool operator==(const Node &other) const;
156        virtual void write(StringTrieBuilder &builder);
157    private:
158        const UChar *s;
159    };
160#endif
161
162    virtual Node *createLinearMatchNode(int32_t i, int32_t unitIndex, int32_t length,
163                                        Node *nextNode) const;
164
165    UBool ensureCapacity(int32_t length);
166    virtual int32_t write(int32_t unit);
167    int32_t write(const UChar *s, int32_t length);
168    virtual int32_t writeElementUnits(int32_t i, int32_t unitIndex, int32_t length);
169    virtual int32_t writeValueAndFinal(int32_t i, UBool isFinal);
170    virtual int32_t writeValueAndType(UBool hasValue, int32_t value, int32_t node);
171    virtual int32_t writeDeltaTo(int32_t jumpTarget);
172
173    UnicodeString strings;
174    UCharsTrieElement *elements;
175    int32_t elementsCapacity;
176    int32_t elementsLength;
177
178    // UChar serialization of the trie.
179    // Grows from the back: ucharsLength measures from the end of the buffer!
180    UChar *uchars;
181    int32_t ucharsCapacity;
182    int32_t ucharsLength;
183};
184
185U_NAMESPACE_END
186
187#endif  // __UCHARSTRIEBUILDER_H__
188