icuSources/common/unicode/ucharstriebuilder.h

   1 /*
   2 *******************************************************************************
   3 *   Copyright (C) 2010-2016, 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
  28 U_NAMESPACE_BEGIN
  29
  30 class UCharsTrieElement;
  31
  32 /**
  33  * Builder class for UCharsTrie.
  34  *
  35  * This class is not intended for public subclassing.
  36  * @stable ICU 4.8
  37  */
  38 class U_COMMON_API UCharsTrieBuilder : public StringTrieBuilder {
  39 public:
  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
 129 private:
 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     class UCTLinearMatchNode : public LinearMatchNode {
 152     public:
 153         UCTLinearMatchNode(const UChar *units, int32_t len, Node *nextNode);
 154         virtual UBool operator==(const Node &other) const;
 155         virtual void write(StringTrieBuilder &builder);
 156     private:
 157         const UChar *s;
 158     };
 159
 160     virtual Node *createLinearMatchNode(int32_t i, int32_t unitIndex, int32_t length,
 161                                         Node *nextNode) const;
 162
 163     UBool ensureCapacity(int32_t length);
 164     virtual int32_t write(int32_t unit);
 165     int32_t write(const UChar *s, int32_t length);
 166     virtual int32_t writeElementUnits(int32_t i, int32_t unitIndex, int32_t length);
 167     virtual int32_t writeValueAndFinal(int32_t i, UBool isFinal);
 168     virtual int32_t writeValueAndType(UBool hasValue, int32_t value, int32_t node);
 169     virtual int32_t writeDeltaTo(int32_t jumpTarget);
 170
 171     UnicodeString strings;
 172     UCharsTrieElement *elements;
 173     int32_t elementsCapacity;
 174     int32_t elementsLength;
 175
 176     // UChar serialization of the trie.
 177     // Grows from the back: ucharsLength measures from the end of the buffer!
 178     UChar *uchars;
 179     int32_t ucharsCapacity;
 180     int32_t ucharsLength;
 181 };
 182
 183 U_NAMESPACE_END
 184
 185 #endif  // __UCHARSTRIEBUILDER_H__