src/core/CLucene/index/_TermInfosWriter.h

/*------------------------------------------------------------------------------
* Copyright (C) 2003-2006 Ben van Klinken and the CLucene Team
*
* Distributable under the terms of either the Apache License (Version 2.0) or
* the GNU Lesser General Public License, as specified in the COPYING file.
------------------------------------------------------------------------------*/
#ifndef _lucene_index_TermInfosWriter_
#define _lucene_index_TermInfosWriter_

#include "CLucene/util/Array.h"

CL_CLASS_DEF(store, Directory)
//#include "FieldInfos.h"
//#include "TermInfo.h"
#include "Term.h"

CL_NS_DEF(index)
class FieldInfos;
class TermInfo;

template <typename T>
class STermInfosWriter : LUCENE_BASE {
private:
    FieldInfos *fieldInfos;
    CL_NS(store)::IndexOutput *output;
    TermInfo *lastTi;
    int64_t size = 0;
    int64_t tisSize = 0;

    int64_t lastIndexPointer;
    bool isIndex;
    CL_NS(util)::ValueArray<T> lastTermText;
    int32_t lastTermTextLength;
    int32_t lastFieldNumber;

    CL_NS(util)::ValueArray<T> termTextBuffer;

    STermInfosWriter *other;

    //inititalize
    STermInfosWriter(CL_NS(store)::Directory *directory, const char *segment, FieldInfos *fis, int32_t interval, bool isIndex);

    int32_t compareToLastTerm(int32_t fieldNumber, const T *termText, int32_t length);

public:
    int32_t maxSkipLevels;

    LUCENE_STATIC_CONSTANT(int32_t, FORMAT = -4);
    LUCENE_STATIC_CONSTANT(int32_t, DEFAULT_TERMDOCS_SKIP_INTERVAL = PFOR_BLOCK_SIZE);

    int32_t indexInterval;// = 128
    int32_t skipInterval;// = 16

    STermInfosWriter(CL_NS(store)::Directory *directory, const char *segment, FieldInfos *fis, int32_t interval);

    ~STermInfosWriter() override;

    void add(STerm<T> *term, TermInfo *ti);

    void add(int32_t fieldNumber, const T *termText, int32_t termTextLength, const TermInfo *ti);

    void close();

private:
    void initialise(CL_NS(store)::Directory *directory, const char *segment, int32_t interval, bool IsIndex);
    void writeTerm(int32_t fieldNumber, const T *termText, int32_t termTextLength);
};

// This stores a monotonically increasing set of <Term, TermInfo> pairs in a
// Directory.  A TermInfos can be written once, in order.
class TermInfosWriter : LUCENE_BASE {
private:
    FieldInfos *fieldInfos;
    CL_NS(store)::IndexOutput *output;
    TermInfo *lastTi;
    int64_t size = 0;
    int64_t tisSize = 0;

    int64_t lastIndexPointer;
    bool isIndex;
    CL_NS(util)::ValueArray<TCHAR> lastTermText;
    int32_t lastTermTextLength;
    int32_t lastFieldNumber;

    CL_NS(util)::ValueArray<TCHAR> termTextBuffer;

    TermInfosWriter *other;

    //inititalize
    TermInfosWriter(CL_NS(store)::Directory *directory, const char *segment, FieldInfos *fis, int32_t interval, bool isIndex);

    int32_t compareToLastTerm(int32_t fieldNumber, const TCHAR *termText, int32_t length);

public:
    /** Expert: The maximum number of skip levels. Smaller values result in
    * slightly smaller indexes, but slower skipping in big posting lists.
    */
    int32_t maxSkipLevels;

    /** The file format version, a negative number. */
    LUCENE_STATIC_CONSTANT(int32_t, FORMAT = -4);

    //Expert: The fraction of {@link TermDocs} entries stored in skip tables,
    //used to accellerate {@link TermDocs#skipTo(int)}.  Larger values result in
    //smaller indices, greater acceleration, but fewer accelerable cases, while
    //smaller values result in bigger indices, less acceleration and more
    //accelerable cases. More detailed experiments would be useful here. */
    LUCENE_STATIC_CONSTANT(int32_t, DEFAULT_TERMDOCS_SKIP_INTERVAL = PFOR_BLOCK_SIZE);


    /**
		* Expert: The fraction of terms in the "dictionary" which should be stored
		* in RAM.  Smaller values use more memory, but make searching slightly
		* faster, while larger values use less memory and make searching slightly
		* slower.  Searching is typically not dominated by dictionary lookup, so
		* tweaking this is rarely useful.
		*/
    int32_t indexInterval;// = 128

    /**
		* Expert: The fraction of {@link TermDocs} entries stored in skip tables,
		* used to accellerate {@link TermDocs#SkipTo(int32_t)}.  Larger values result in
		* smaller indexes, greater acceleration, but fewer accelerable cases, while
		* smaller values result in bigger indexes, less acceleration and more
		* accelerable cases. More detailed experiments would be useful here.
		*/
    int32_t skipInterval;// = 16

    TermInfosWriter(CL_NS(store)::Directory *directory, const char *segment, FieldInfos *fis, int32_t interval);

    ~TermInfosWriter();


    void add(Term *term, TermInfo *ti);

    /** Adds a new <<fieldNumber, termText>, TermInfo> pair to the set.
    Term must be lexicographically greater than all previous Terms added.
    TermInfo pointers must be positive and greater than all previous.*/
    void add(int32_t fieldNumber, const TCHAR *termText, int32_t termTextLength, const TermInfo *ti);

    /** Called to complete TermInfos creation. */
    void close();

private:
    /** Helps constructors to initialize instances */
    void initialise(CL_NS(store)::Directory *directory, const char *segment, int32_t interval, bool IsIndex);
    void writeTerm(int32_t fieldNumber, const TCHAR *termText, int32_t termTextLength);
};
CL_NS_END
#endif