ExtraWeightPostList Class Reference

A postlist which adds on an extra weight contribution. More...

#include <extraweightpostlist.h>

Inheritance diagram for ExtraWeightPostList:

[legend]Collaboration diagram for ExtraWeightPostList:


Public Member Functions
Xapian::doccount	get_termfreq_max () const
	Get an upper bound on the number of documents indexed by this term.
Xapian::doccount	get_termfreq_min () const
	Get a lower bound on the number of documents indexed by this term.
Xapian::doccount	get_termfreq_est () const
	Get an estimate of the number of documents indexed by this term.
Xapian::docid	get_docid () const
	Return the current docid.
Xapian::weight	get_weight () const
	Return the weight contribution for the current position.
Xapian::weight	get_maxweight () const
	Return an upper bound on what get_weight() can return.
Xapian::weight	recalc_maxweight ()
	Recalculate the upper bound on what get_weight() can return.
PostList *	next (Xapian::weight w_min)
	Advance the current position to the next document in the postlist.
PostList *	skip_to (Xapian::docid did, Xapian::weight w_min)
	Skip forward to the specified docid.
bool	at_end () const
	Return true if the current position is past the last entry in this list.
std::string	get_description () const
	Return a string description of this object.
virtual Xapian::doclength	get_doclength () const
	Return the document length of the document the current term comes from.
virtual PositionList *	read_position_list ()
	Read the position list for the term in the current document and return a pointer to it (owned by the PostList).
virtual PositionList *	open_position_list () const
	Read the position list for the term in the current document and return a pointer to it (not owned by the PostList).
	ExtraWeightPostList (PostList pl_, Xapian::Weight wt_, MultiMatch *matcher_)
	~ExtraWeightPostList ()
Private Attributes
PostList *	pl
Xapian::Weight *	wt
MultiMatch *	matcher
Xapian::weight	max_weight

Detailed Description

A postlist which adds on an extra weight contribution.

Definition at line 29 of file extraweightpostlist.h.

Constructor & Destructor Documentation

ExtraWeightPostList::ExtraWeightPostList	(	PostList *	pl_,
		Xapian::Weight *	wt_,
		MultiMatch *	matcher_
	)			`[inline]`

Definition at line 102 of file extraweightpostlist.h.

ExtraWeightPostList::~ExtraWeightPostList ( ) [inline]

Definition at line 108 of file extraweightpostlist.h.

References pl, and wt.

Member Function Documentation

Xapian::doccount ExtraWeightPostList::get_termfreq_max ( ) const [inline, virtual]

Get an upper bound on the number of documents indexed by this term.

Implements Xapian::PostingIterator::Internal.

Definition at line 37 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_termfreq_max(), and pl.

Xapian::doccount ExtraWeightPostList::get_termfreq_min ( ) const [inline, virtual]

Get a lower bound on the number of documents indexed by this term.

Implements Xapian::PostingIterator::Internal.

Definition at line 40 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_termfreq_min(), and pl.

Xapian::doccount ExtraWeightPostList::get_termfreq_est ( ) const [inline, virtual]

Get an estimate of the number of documents indexed by this term.

It should always be true that: get_termfreq_min() <= get_termfreq_est() <= get_termfreq_max()

Implements Xapian::PostingIterator::Internal.

Definition at line 43 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_termfreq_est(), and pl.

Xapian::docid ExtraWeightPostList::get_docid ( ) const [inline, virtual]

Return the current docid.

Implements Xapian::PostingIterator::Internal.

Definition at line 47 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_docid(), and pl.

Xapian::weight ExtraWeightPostList::get_weight ( ) const [inline, virtual]

Return the weight contribution for the current position.

Implements Xapian::PostingIterator::Internal.

Definition at line 49 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_doclength(), Xapian::Weight::get_sumextra(), Xapian::PostingIterator::Internal::get_weight(), pl, and wt.

Xapian::weight ExtraWeightPostList::get_maxweight ( ) const [inline, virtual]

Return an upper bound on what get_weight() can return.

Implements Xapian::PostingIterator::Internal.

Definition at line 53 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_maxweight(), max_weight, and pl.

Xapian::weight ExtraWeightPostList::recalc_maxweight ( ) [inline, virtual]

Recalculate the upper bound on what get_weight() can return.

If the tree has pruned, get_maxweight() may use cached values. Calling this method instead forces a full recalculation.

Implements Xapian::PostingIterator::Internal.

Definition at line 57 of file extraweightpostlist.h.

References max_weight, pl, and Xapian::PostingIterator::Internal::recalc_maxweight().

PostList* ExtraWeightPostList::next ( Xapian::weight w_min ) [inline, virtual]

Advance the current position to the next document in the postlist.

The list starts before the first entry in the list, so next() must be called before any methods which need the context of the current position.

Parameters:

w_min

The minimum weight contribution that is needed (this is just a hint which PostList subclasses may ignore).

Returns:: If a non-NULL pointer is returned, then the caller should substitute the returned pointer for its pointer to us, and then delete us. This "pruning" can only happen for a non-leaf subclass of this class.

Implements Xapian::PostingIterator::Internal.

Definition at line 61 of file extraweightpostlist.h.

References matcher, max_weight, Xapian::PostingIterator::Internal::next(), pl, and MultiMatch::recalc_maxweight().

PostList* ExtraWeightPostList::skip_to	(	Xapian::docid	,
		Xapian::weight	w_min
	)			`[inline, virtual]`

Skip forward to the specified docid.

If the specified docid isn't in the list, position ourselves on the first document after it (or at_end() if no greater docids are present).

Parameters:

w_min

The minimum weight contribution that is needed (this is just a hint which PostList subclasses may ignore).

Returns:: If a non-NULL pointer is returned, then the caller should substitute the returned pointer for its pointer to us, and then delete us. This "pruning" can only happen for a non-leaf subclass of this class.

Implements Xapian::PostingIterator::Internal.

Definition at line 71 of file extraweightpostlist.h.

References matcher, max_weight, pl, MultiMatch::recalc_maxweight(), and Xapian::PostingIterator::Internal::skip_to().

bool ExtraWeightPostList::at_end ( ) const [inline, virtual]

Return true if the current position is past the last entry in this list.

Implements Xapian::PostingIterator::Internal.

Definition at line 81 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::at_end(), and pl.

std::string ExtraWeightPostList::get_description ( ) const [inline, virtual]

Return a string description of this object.

Implements Xapian::PostingIterator::Internal.

Definition at line 83 of file extraweightpostlist.h.