oofWordParser Class Reference
[OOFILE utility classes and functions.]

#include <oofwords.h>

Inheritance diagram for oofWordParser:

[legend]Collaboration diagram for oofWordParser:

[legend]List of all members.

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Detailed Description

Base class for user-replaceable word parser.

Used mainly to search tables and word-indexable fields. Default behaviour in this base class is used if no overriding default object is attached to a table or dbConnection.

includes stop-word list and minimum length. Doesn't do any stemming or more complex parsing.

A word is generated from the isalnum() chars between each isspace() separators. Any non alnum chars inside a word are skipped.

mpString remains a pointer to the start of the current word. mWord is updated (in theory) with the filtered copy of the word.

Bug:

SPOTTED 14 Nov 2000 - calling start() again after using parser doesn't update mWord

To aid in search implementation, generateWordArray() creates a separate list of strings which is retained and can be accessed by generatedStrings() and generatedCount()

See also:

dbTable::searchSelContainsAnyOf for example of use.

Note:

not to be regarded as good example of programming style until parser cleaned up and storage neater!

Todo:

cleaner abstraction of word source iteration

work out why minWordLength returns a reference and add setter if necessary

Public Member Functions
	oofWordParser (const char *stringToParse=0, unsigned short minWordLen=3, const char **stopWords=0, unsigned short numStopWords=0)
virtual	~oofWordParser ()
	dtor.
virtual void	start ()
	sets the oofWordParser to the start of the string.
virtual void	start (const char *stringToParse)
	call to start parsing different string
virtual void	next (void)
	Find the next word, updating the mWord pointer returned by word();.
virtual bool	more () const
	return true if any words left.
virtual const char *	word () const
	returns the current word.
virtual const char *	wordString () const
	returns the original string.
virtual unsigned short &	minWordLength ()
	returns/sets the minimum word length cut-off.
virtual bool	isValidWord (const char *) const
virtual void	generateSearchArray ()
const char **	generatedStrings () const
	return array of pointers to individual words.
unsigned long	generatedCount () const
void	extract (std::ostream &)
void	incRefs ()
void	decRefs ()
Protected Types
enum	{ maxWordLength = 40 }
Protected Attributes
const char *	mpString
	pointer to start of words to process, may point to mGeneratedStrings entries
const char *	mpStringStart
	pointer to original strings
char	mWord [maxWordLength]
unsigned short	mWordLength
unsigned short	mMinWordLength
const char **	mStopWords
	passed in list of stop words to ignore
unsigned short	mNumStopWords
const char **	mGeneratedStrings
	owned strings generated for subsearch call
unsigned long	mGeneratedCount
unsigned long	mIterStrings
unsigned int	mReferences

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Member Enumeration Documentation

anonymous enum [protected]

Enumeration values: maxWordLength

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Constructor & Destructor Documentation

oofWordParser::oofWordParser (  const char *  stringToParse = 0, unsigned short  minWordLen = 3, const char **  stopWords = 0, unsigned short  numStopWords = 0 )

oofWordParser::~oofWordParser (   )  [virtual]

dtor. Delete the const char* strings owned in mGeneratedStrings, if we ever generated them! Todo: fix mGeneratedWords management so deletes without complaint

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Member Function Documentation

void OOF_mixRefCount::decRefs (   )  [inherited]

void oofWordParser::extract (  std::ostream &   )

unsigned long oofWordParser::generatedCount (   )  const [inline]

const char ** oofWordParser::generatedStrings (   )  const [inline]

return array of pointers to individual words.

void oofWordParser::generateSearchArray (   )  [virtual]

Todo: make more efficient

void OOF_mixRefCount::incRefs (   )  [inline, inherited]

bool oofWordParser::isValidWord (  const char *   )  const [virtual]

unsigned short & oofWordParser::minWordLength (   )  [virtual]

returns/sets the minimum word length cut-off.

bool oofWordParser::more (   )  const [virtual]

return true if any words left. Todo: make this more reliable, preparse the next word at next() and start()

void oofWordParser::next (  void   )  [virtual]

Find the next word, updating the mWord pointer returned by word();. Todo: refactor to isolate the common parsing code in start() & here Note: I don't know who wrote this - it wasn't Andy!

void oofWordParser::start (  const char *  stringToParse  )  [virtual]

call to start parsing different string

void oofWordParser::start (   )  [virtual]

sets the oofWordParser to the start of the string. Todo: Fix existing bug where re-starts do NOT reset the content of mWord. Note that both start(const char*) and next() have a copy to mWord which further filters the letters!!!!

const char * oofWordParser::word (   )  const [virtual]

returns the current word.

const char * oofWordParser::wordString (   )  const [virtual]

returns the original string.

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Member Data Documentation

unsigned long oofWordParser::mGeneratedCount [protected]

const char** oofWordParser::mGeneratedStrings [protected]

owned strings generated for subsearch call

unsigned long oofWordParser::mIterStrings [protected]

unsigned short oofWordParser::mMinWordLength [protected]

unsigned short oofWordParser::mNumStopWords [protected]

const char* oofWordParser::mpString [protected]

pointer to start of words to process, may point to mGeneratedStrings entries

const char* oofWordParser::mpStringStart [protected]

pointer to original strings

unsigned int OOF_mixRefCount::mReferences [protected, inherited]

const char** oofWordParser::mStopWords [protected]

passed in list of stop words to ignore

char oofWordParser::mWord[maxWordLength] [protected]

unsigned short oofWordParser::mWordLength [protected]

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The documentation for this class was generated from the following files:

• oofwords.h
• oofwords.cpp

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