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// © 2016 and later: Unicode, Inc. and others.
/*
*******************************************************************************
* Copyright (C) 2010-2016, International Business Machines
* Corporation and others. All Rights Reserved.
*******************************************************************************
* file name: bytestriebuilder.h
* encoding: UTF-8
* tab size: 8 (not used)
* indentation:4
*
* created on: 2010sep25
* created by: Markus W. Scherer
*/
/**
* \file
* \brief C++ API: Builder for icu::BytesTrie
*/
#ifndef __BYTESTRIEBUILDER_H__
#define __BYTESTRIEBUILDER_H__
#include "unicode/utypes.h"
#if U_SHOW_CPLUSPLUS_API
#include "unicode/bytestrie.h"
#include "unicode/stringpiece.h"
#include "unicode/stringtriebuilder.h"
class BytesTrieTest;
U_NAMESPACE_BEGIN
class BytesTrieElement;
class CharString;
/**
* Builder class for BytesTrie.
*
* This class is not intended for public subclassing.
* @stable ICU 4.8
*/
class U_COMMON_API BytesTrieBuilder : public StringTrieBuilder {
public:
/**
* Constructs an empty builder.
* @param errorCode Standard ICU error code.
* @stable ICU 4.8
*/
BytesTrieBuilder(UErrorCode &errorCode);
/**
* Destructor.
* @stable ICU 4.8
*/
virtual ~BytesTrieBuilder();
/**
* Adds a (byte sequence, value) pair.
* The byte sequence must be unique.
* The bytes will be copied; the builder does not keep
* a reference to the input StringPiece or its data().
* @param s The input byte sequence.
* @param value The value associated with this byte sequence.
* @param errorCode Standard ICU error code. Its input value must
* pass the U_SUCCESS() test, or else the function returns
* immediately. Check for U_FAILURE() on output or use with
* function chaining. (See User Guide for details.)
* @return *this
* @stable ICU 4.8
*/
BytesTrieBuilder &add(StringPiece s, int32_t value, UErrorCode &errorCode);
/**
* Builds a BytesTrie for the add()ed data.
* Once built, no further data can be add()ed until clear() is called.
*
* A BytesTrie cannot be empty. At least one (byte sequence, value) pair
* must have been add()ed.
*
* This method passes ownership of the builder's internal result array to the new trie object.
* Another call to any build() variant will re-serialize the trie.
* After clear() has been called, a new array will be used as well.
* @param buildOption Build option, see UStringTrieBuildOption.
* @param errorCode Standard ICU error code. Its input value must
* pass the U_SUCCESS() test, or else the function returns
* immediately. Check for U_FAILURE() on output or use with
* function chaining. (See User Guide for details.)
* @return A new BytesTrie for the add()ed data.
* @stable ICU 4.8
*/
BytesTrie *build(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
/**
* Builds a BytesTrie for the add()ed data and byte-serializes it.
* Once built, no further data can be add()ed until clear() is called.
*
* A BytesTrie cannot be empty. At least one (byte sequence, value) pair
* must have been add()ed.
*
* Multiple calls to buildStringPiece() return StringPieces referring to the
* builder's same byte array, without rebuilding.
* If buildStringPiece() is called after build(), the trie will be
* re-serialized into a new array (because build() passes on ownership).
* If build() is called after buildStringPiece(), the trie object returned
* by build() will become the owner of the underlying string for the
* previously returned StringPiece.
* After clear() has been called, a new array will be used as well.
* @param buildOption Build option, see UStringTrieBuildOption.
* @param errorCode Standard ICU error code. Its input value must
* pass the U_SUCCESS() test, or else the function returns
* immediately. Check for U_FAILURE() on output or use with
* function chaining. (See User Guide for details.)
* @return A StringPiece which refers to the byte-serialized BytesTrie for the add()ed data.
* @stable ICU 4.8
*/
StringPiece buildStringPiece(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
/**
* Removes all (byte sequence, value) pairs.
* New data can then be add()ed and a new trie can be built.
* @return *this
* @stable ICU 4.8
*/
BytesTrieBuilder &clear();
private:
friend class ::BytesTrieTest;
BytesTrieBuilder(const BytesTrieBuilder &other) = delete; // no copy constructor
BytesTrieBuilder &operator=(const BytesTrieBuilder &other) = delete; // no assignment operator
void buildBytes(UStringTrieBuildOption buildOption, UErrorCode &errorCode);
virtual int32_t getElementStringLength(int32_t i) const override;
virtual char16_t getElementUnit(int32_t i, int32_t byteIndex) const override;
virtual int32_t getElementValue(int32_t i) const override;
virtual int32_t getLimitOfLinearMatch(int32_t first, int32_t last, int32_t byteIndex) const override;
virtual int32_t countElementUnits(int32_t start, int32_t limit, int32_t byteIndex) const override;
virtual int32_t skipElementsBySomeUnits(int32_t i, int32_t byteIndex, int32_t count) const override;
virtual int32_t indexOfElementWithNextUnit(int32_t i, int32_t byteIndex, char16_t byte) const override;
virtual UBool matchNodesCanHaveValues() const override { return false; }
virtual int32_t getMaxBranchLinearSubNodeLength() const override { return BytesTrie::kMaxBranchLinearSubNodeLength; }
virtual int32_t getMinLinearMatch() const override { return BytesTrie::kMinLinearMatch; }
virtual int32_t getMaxLinearMatchLength() const override { return BytesTrie::kMaxLinearMatchLength; }
/**
* @internal (private)
*/
class BTLinearMatchNode : public LinearMatchNode {
public:
BTLinearMatchNode(const char *units, int32_t len, Node *nextNode);
virtual bool operator==(const Node &other) const override;
virtual void write(StringTrieBuilder &builder) override;
private:
const char *s;
};
virtual Node *createLinearMatchNode(int32_t i, int32_t byteIndex, int32_t length,
Node *nextNode) const override;
UBool ensureCapacity(int32_t length);
virtual int32_t write(int32_t byte) override;
int32_t write(const char *b, int32_t length);
virtual int32_t writeElementUnits(int32_t i, int32_t byteIndex, int32_t length) override;
virtual int32_t writeValueAndFinal(int32_t i, UBool isFinal) override;
virtual int32_t writeValueAndType(UBool hasValue, int32_t value, int32_t node) override;
virtual int32_t writeDeltaTo(int32_t jumpTarget) override;
static int32_t internalEncodeDelta(int32_t i, char intBytes[]);
CharString *strings; // Pointer not object so we need not #include internal charstr.h.
BytesTrieElement *elements;
int32_t elementsCapacity;
int32_t elementsLength;
// Byte serialization of the trie.
// Grows from the back: bytesLength measures from the end of the buffer!
char *bytes;
int32_t bytesCapacity;
int32_t bytesLength;
};
U_NAMESPACE_END
#endif /* U_SHOW_CPLUSPLUS_API */
#endif // __BYTESTRIEBUILDER_H__