icuSources/common/unicode/ucharstriebuilder.h

   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:  ucharstriebuilder.h
   9 *   encoding:   UTF-8
  10 *   tab size:   8 (not used)
  11 *   indentation:4
  12 *
  13 *   created on: 2010nov14
  14 *   created by: Markus W. Scherer
  15 */
  16
  17 #ifndef __UCHARSTRIEBUILDER_H__
  18 #define __UCHARSTRIEBUILDER_H__
  19
  20 #include "unicode/utypes.h"
  21
  22 #if U_SHOW_CPLUSPLUS_API
  23
  24 #include "unicode/stringtriebuilder.h"
  25 #include "unicode/ucharstrie.h"
  26 #include "unicode/unistr.h"
  27
  28 /**
  29  * \file
  30  * \brief C++ API: Builder for icu::UCharsTrie
  31  */
  32
  33 U_NAMESPACE_BEGIN
  34
  35 class UCharsTrieElement;
  36
  37 /**
  38  * Builder class for UCharsTrie.
  39  *
  40  * This class is not intended for public subclassing.
  41  * @stable ICU 4.8
  42  */
  43 class U_COMMON_API UCharsTrieBuilder : public StringTrieBuilder {
  44 public:
  45     /**
  46      * Constructs an empty builder.
  47      * @param errorCode Standard ICU error code.
  48      * @stable ICU 4.8
  49      */
  50     UCharsTrieBuilder(UErrorCode &errorCode);
  51
  52     /**
  53      * Destructor.
  54      * @stable ICU 4.8
  55      */
  56     virtual ~UCharsTrieBuilder();
  57
  58     /**
  59      * Adds a (string, value) pair.
  60      * The string must be unique.
  61      * The string contents will be copied; the builder does not keep
  62      * a reference to the input UnicodeString or its buffer.
  63      * @param s The input string.
  64      * @param value The value associated with this string.
  65      * @param errorCode Standard ICU error code. Its input value must
  66      *                  pass the U_SUCCESS() test, or else the function returns
  67      *                  immediately. Check for U_FAILURE() on output or use with
  68      *                  function chaining. (See User Guide for details.)
  69      * @return *this
  70      * @stable ICU 4.8
  71      */
  72     UCharsTrieBuilder &add(const UnicodeString &s, int32_t value, UErrorCode &errorCode);
  73
  74     /**
  75      * Builds a UCharsTrie for the add()ed data.
  76      * Once built, no further data can be add()ed until clear() is called.
  77      *
  78      * A UCharsTrie cannot be empty. At least one (string, value) pair
  79      * must have been add()ed.
  80      *
  81      * This method passes ownership of the builder's internal result array to the new trie object.
  82      * Another call to any build() variant will re-serialize the trie.
  83      * After clear() has been called, a new array will be used as well.
  84      * @param buildOption Build option, see UStringTrieBuildOption.
  85      * @param errorCode Standard ICU error code. Its input value must
  86      *                  pass the U_SUCCESS() test, or else the function returns
  87      *                  immediately. Check for U_FAILURE() on output or use with
  88      *                  function chaining. (See User Guide for details.)
  89      * @return A new UCharsTrie for the add()ed data.
  90      * @stable ICU 4.8
  91      */
  92     UCharsTrie *build(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
  93
  94     /**
  95      * Builds a UCharsTrie for the add()ed data and char16_t-serializes it.
  96      * Once built, no further data can be add()ed until clear() is called.
  97      *
  98      * A UCharsTrie cannot be empty. At least one (string, value) pair
  99      * must have been add()ed.
 100      *
 101      * Multiple calls to buildUnicodeString() set the UnicodeStrings to the
 102      * builder's same char16_t array, without rebuilding.
 103      * If buildUnicodeString() is called after build(), the trie will be
 104      * re-serialized into a new array.
 105      * If build() is called after buildUnicodeString(), the trie object will become
 106      * the owner of the previously returned array.
 107      * After clear() has been called, a new array will be used as well.
 108      * @param buildOption Build option, see UStringTrieBuildOption.
 109      * @param result A UnicodeString which will be set to the char16_t-serialized
 110      *               UCharsTrie for the add()ed data.
 111      * @param errorCode Standard ICU error code. Its input value must
 112      *                  pass the U_SUCCESS() test, or else the function returns
 113      *                  immediately. Check for U_FAILURE() on output or use with
 114      *                  function chaining. (See User Guide for details.)
 115      * @return result
 116      * @stable ICU 4.8
 117      */
 118     UnicodeString &buildUnicodeString(UStringTrieBuildOption buildOption, UnicodeString &result,
 119                                       UErrorCode &errorCode);
 120
 121     /**
 122      * Removes all (string, 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     UCharsTrieBuilder &clear() {
 128         strings.remove();
 129         elementsLength=0;
 130         ucharsLength=0;
 131         return *this;
 132     }
 133
 134 private:
 135     UCharsTrieBuilder(const UCharsTrieBuilder &other);  // no copy constructor
 136     UCharsTrieBuilder &operator=(const UCharsTrieBuilder &other);  // no assignment operator
 137
 138     void buildUChars(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
 139
 140     virtual int32_t getElementStringLength(int32_t i) const;
 141     virtual char16_t getElementUnit(int32_t i, int32_t unitIndex) const;
 142     virtual int32_t getElementValue(int32_t i) const;
 143
 144     virtual int32_t getLimitOfLinearMatch(int32_t first, int32_t last, int32_t unitIndex) const;
 145
 146     virtual int32_t countElementUnits(int32_t start, int32_t limit, int32_t unitIndex) const;
 147     virtual int32_t skipElementsBySomeUnits(int32_t i, int32_t unitIndex, int32_t count) const;
 148     virtual int32_t indexOfElementWithNextUnit(int32_t i, int32_t unitIndex, char16_t unit) const;
 149
 150     virtual UBool matchNodesCanHaveValues() const { return TRUE; }
 151
 152     virtual int32_t getMaxBranchLinearSubNodeLength() const { return UCharsTrie::kMaxBranchLinearSubNodeLength; }
 153     virtual int32_t getMinLinearMatch() const { return UCharsTrie::kMinLinearMatch; }
 154     virtual int32_t getMaxLinearMatchLength() const { return UCharsTrie::kMaxLinearMatchLength; }
 155
 156     class UCTLinearMatchNode : public LinearMatchNode {
 157     public:
 158         UCTLinearMatchNode(const char16_t *units, int32_t len, Node *nextNode);
 159         virtual UBool operator==(const Node &other) const;
 160         virtual void write(StringTrieBuilder &builder);
 161     private:
 162         const char16_t *s;
 163     };
 164
 165     virtual Node *createLinearMatchNode(int32_t i, int32_t unitIndex, int32_t length,
 166                                         Node *nextNode) const;
 167
 168     UBool ensureCapacity(int32_t length);
 169     virtual int32_t write(int32_t unit);
 170     int32_t write(const char16_t *s, int32_t length);
 171     virtual int32_t writeElementUnits(int32_t i, int32_t unitIndex, int32_t length);
 172     virtual int32_t writeValueAndFinal(int32_t i, UBool isFinal);
 173     virtual int32_t writeValueAndType(UBool hasValue, int32_t value, int32_t node);
 174     virtual int32_t writeDeltaTo(int32_t jumpTarget);
 175
 176     UnicodeString strings;
 177     UCharsTrieElement *elements;
 178     int32_t elementsCapacity;
 179     int32_t elementsLength;
 180
 181     // char16_t serialization of the trie.
 182     // Grows from the back: ucharsLength measures from the end of the buffer!
 183     char16_t *uchars;
 184     int32_t ucharsCapacity;
 185     int32_t ucharsLength;
 186 };
 187
 188 U_NAMESPACE_END
 189
 190 #endif /* U_SHOW_CPLUSPLUS_API */
 191
 192 #endif  // __UCHARSTRIEBUILDER_H__