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// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
******************************************************************************
* Copyright (C) 1996-2012, International Business Machines *
* Corporation and others. All Rights Reserved. *
******************************************************************************
*/
/**
* \file
* \brief Originally, added as C++ API for Collation data used to compute minLengthInChars
* \internal
*/
/*
* Note: This module was incldued in ICU 4.0.1 as @internal technology preview for supporting
* Boyer-Moore string search API. For now, only SSearchTest depends on this module. I temporaly
* moved the module from i18n directory to intltest, because we have no plan to publish this
* as public API. (2012-12-18 yoshito)
*/
#ifndef COLL_DATA_H
#define COLL_DATA_H
#include "unicode/utypes.h"
#if !UCONFIG_NO_COLLATION
#include "unicode/ucol.h"
#include "unicode/unistr.h"
/**
* The size of the internal CE buffer in a <code>CEList</code> object
*/
#define CELIST_BUFFER_SIZE 4
/**
* \def INSTRUMENT_CELIST
* Define this to enable the <code>CEList</code> objects to collect
* statistics.
*/
/**
* The size of the initial list in a <code>StringList</code> object.
*/
#define STRING_LIST_BUFFER_SIZE 16
U_NAMESPACE_USE
/**
* This object holds a list of CEs generated from a particular
* <code>UnicodeString</code>
*
*/
class CEList
{
public:
/**
* Construct a <code>CEList</code> object.
*
* @param coll - the Collator used to collect the CEs.
* @param string - the string for which to collect the CEs.
* @param status - will be set if any errors occur.
*
* Note: if on return, status is set to an error code,
* the only safe thing to do with this object is to call
* the destructor.
*/
CEList(UCollator *coll, const UnicodeString &string, UErrorCode &status);
/**
* The destructor.
*/
~CEList();
/**
* Return the number of CEs in the list.
*
* @return the number of CEs in the list.
*/
int32_t size() const;
/**
* Get a particular CE from the list.
*
* @param index - the index of the CE to return
*
* @return the CE, or <code>0</code> if <code>index</code> is out of range
*/
uint32_t get(int32_t index) const;
/**
* Check if the CEs in another <code>CEList</code> match the
* suffix of this list starting at a give offset.
*
* @param offset - the offset of the suffix
* @param other - the other <code>CEList</code>
*
* @return <code>TRUE</code> if the CEs match, <code>FALSE</code> otherwise.
*/
UBool matchesAt(int32_t offset, const CEList *other) const;
/**
* The index operator.
*
* @param index - the index
*
* @return a reference to the given CE in the list
*/
uint32_t &operator[](int32_t index) const;
private:
void add(uint32_t ce, UErrorCode &status);
uint32_t ceBuffer[CELIST_BUFFER_SIZE];
uint32_t *ces;
int32_t listMax;
int32_t listSize;
};
/**
* StringList
*
* This object holds a list of <code>UnicodeString</code> objects.
*/
class StringList
{
public:
/**
* Construct an empty <code>StringList</code>
*
* @param status - will be set if any errors occur.
*
* Note: if on return, status is set to an error code,
* the only safe thing to do with this object is to call
* the destructor.
*/
StringList(UErrorCode &status);
/**
* The destructor.
*/
~StringList();
/**
* Add a string to the list.
*
* @param string - the string to add
* @param status - will be set if any errors occur.
*/
void add(const UnicodeString *string, UErrorCode &status);
/**
* Add an array of Unicode code points to the list.
*
* @param chars - the address of the array of code points
* @param count - the number of code points in the array
* @param status - will be set if any errors occur.
*/
void add(const UChar *chars, int32_t count, UErrorCode &status);
/**
* Get a particular string from the list.
*
* @param index - the index of the string
*
* @return a pointer to the <code>UnicodeString</code> or <code>NULL</code>
* if <code>index</code> is out of bounds.
*/
const UnicodeString *get(int32_t index) const;
/**
* Get the number of stings in the list.
*
* @return the number of strings in the list.
*/
int32_t size() const;
private:
UnicodeString *strings;
int32_t listMax;
int32_t listSize;
};
/*
* Forward references to internal classes.
*/
class StringToCEsMap;
class CEToStringsMap;
/**
* CollData
*
* This class holds the Collator-specific data needed to
* compute the length of the shortest string that can
* generate a partcular list of CEs.
*
* <code>CollData</code> objects are quite expensive to compute. Because
* of this, they are cached. When you call <code>CollData::open</code> it
* returns a reference counted cached object. When you call <code>CollData::close</code>
* the reference count on the object is decremented but the object is not deleted.
*
* If you do not need to reuse any unreferenced objects in the cache, you can call
* <code>CollData::flushCollDataCache</code>. If you no longer need any <code>CollData</code>
* objects, you can call <code>CollData::freeCollDataCache</code>
*/
class CollData
{
public:
/**
* Construct a <code>CollData</code> object.
*
* @param collator - the collator
* @param status - will be set if any errors occur.
*/
CollData(UCollator *collator, UErrorCode &status);
/**
* The destructor.
*/
~CollData();
/**
* Get the <code>UCollator</code> object used to create this object.
* The object returned may not be the exact object that was used to
* create this object, but it will have the same behavior.
*/
UCollator *getCollator() const;
/**
* Get a list of all the strings which generate a list
* of CEs starting with a given CE.
*
* @param ce - the CE
*
* return a <code>StringList</code> object containing all
* the stirngs, or <code>NULL</code> if there are
* no such strings.
*/
const StringList *getStringList(int32_t ce) const;
/**
* Get a list of the CEs generated by a partcular stirng.
*
* @param string - the string
*
* @return a <code>CEList</code> object containt the CEs. You
* must call <code>freeCEList</code> when you are finished
* using the <code>CEList</code>/
*/
const CEList *getCEList(const UnicodeString *string) const;
/**
* Release a <code>CEList</code> returned by <code>getCEList</code>.
*
* @param list - the <code>CEList</code> to free.
*/
void freeCEList(const CEList *list);
/**
* Return the length of the shortest string that will generate
* the given list of CEs.
*
* @param ces - the CEs
* @param offset - the offset of the first CE in the list to use.
*
* @return the length of the shortest string.
*/
int32_t minLengthInChars(const CEList *ces, int32_t offset) const;
/**
* Return the length of the shortest string that will generate
* the given list of CEs.
*
* Note: the algorithm used to do this computation is recursive. To
* limit the amount of recursion, a "history" list is used to record
* the best answer starting at a particular offset in the list of CEs.
* If the same offset is visited again during the recursion, the answer
* in the history list is used.
*
* @param ces - the CEs
* @param offset - the offset of the first CE in the list to use.
* @param history - the history list. Must be at least as long as
* the number of cEs in the <code>CEList</code>
*
* @return the length of the shortest string.
*/
int32_t minLengthInChars(const CEList *ces, int32_t offset, int32_t *history) const;
private:
UCollator *coll;
CEToStringsMap *ceToCharsStartingWith;
uint32_t minHan;
uint32_t maxHan;
uint32_t jamoLimits[4];
};
#endif // #if !UCONFIG_NO_COLLATION
#endif // #ifndef COLL_DATA_H