MultiPostList Class Reference

#include <multi_postlist.h>

Inheritance diagram for MultiPostList:

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Collaboration diagram for MultiPostList:

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List of all members.

Public Member Functions
	~MultiPostList ()
Xapian::doccount	get_termfreq_min () const
	Get a lower bound on the number of documents indexed by this term.
Xapian::doccount	get_termfreq_max () const
	Get an upper 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::weight	get_maxweight () const
	Return an upper bound on what get_weight() can return.
Xapian::weight	get_weight () const
	Return the weight contribution for the current position.
Xapian::weight	recalc_maxweight ()
	Recalculate the upper bound on what get_weight() can return.
Xapian::docid	get_docid () const
	Return the current docid.
Xapian::termcount	get_doclength () const
	Return the length of current document.
Xapian::termcount	get_wdf () const
	Return the wdf for the document at the current position.
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).
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.
Private Member Functions
	MultiPostList (std::vector< LeafPostList * > &pls, const Xapian::Database &this_db_)
Private Attributes
std::vector< LeafPostList * >	postlists
const Xapian::Database &	this_db
bool	finished
Xapian::docid	currdoc
Xapian::doccount	multiplier
Friends
class	Xapian::Database

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Detailed Description

Definition at line 28 of file multi_postlist.h.

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Constructor & Destructor Documentation

MultiPostList::MultiPostList	(	std::vector< LeafPostList * > &	pls,
		const Xapian::Database &	this_db_
	)			[private]

Definition at line 34 of file multi_postlist.cc.

References multiplier.

MultiPostList::~MultiPostList

(

)

Definition at line 45 of file multi_postlist.cc.

References postlists.

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Member Function Documentation

bool MultiPostList::at_end

(

)

const [virtual]

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

Implements Xapian::PostingIterator::Internal.

Definition at line 195 of file multi_postlist.cc.

References finished.

Referenced by get_docid(), get_doclength(), next(), and skip_to().

std::string MultiPostList::get_description

(

)

const [virtual]

Return a string description of this object.

Implements Xapian::PostingIterator::Internal.

Definition at line 201 of file multi_postlist.cc.

References postlists.

Xapian::docid MultiPostList::get_docid

(

)

const [virtual]

Return the current docid.

Implements Xapian::PostingIterator::Internal.

Definition at line 95 of file multi_postlist.cc.

References Assert, at_end(), currdoc, LOGCALL, and RETURN.

Referenced by get_doclength().

Xapian::termcount MultiPostList::get_doclength

(

)

const [virtual]

Return the length of current document.

Implements Xapian::PostingIterator::Internal.

Definition at line 104 of file multi_postlist.cc.

References Assert, AssertEqParanoid, at_end(), currdoc, get_docid(), Xapian::Database::get_doclength(), LOGCALL, multiplier, postlists, RETURN, and this_db.

Xapian::weight MultiPostList::get_maxweight

(

)

const [virtual]

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

Implements Xapian::PostingIterator::Internal.

Definition at line 75 of file multi_postlist.cc.

References get_weight().

Xapian::doccount MultiPostList::get_termfreq_est

(

)

const [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 69 of file multi_postlist.cc.

References get_termfreq_min().

Xapian::doccount MultiPostList::get_termfreq_max

(

)

const [virtual]

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

Implements Xapian::PostingIterator::Internal.

Definition at line 63 of file multi_postlist.cc.

References get_termfreq_min().

Xapian::doccount MultiPostList::get_termfreq_min

(

)

const [virtual]

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

Implements Xapian::PostingIterator::Internal.

Definition at line 55 of file multi_postlist.cc.

References Assert.

Referenced by get_termfreq_est(), and get_termfreq_max().

Xapian::termcount MultiPostList::get_wdf

(

)

const [virtual]

Return the wdf for the document at the current position.

The default implementation throws Xapian::UnimplementedError.

Reimplemented from Xapian::PostingIterator::Internal.

Definition at line 115 of file multi_postlist.cc.

References currdoc, multiplier, and postlists.

Xapian::weight MultiPostList::get_weight

(

)

const [virtual]

Return the weight contribution for the current position.

Implements Xapian::PostingIterator::Internal.

Definition at line 81 of file multi_postlist.cc.

References Assert.

Referenced by get_maxweight(), and recalc_maxweight().

PostList * MultiPostList::next

(

Xapian::weight

w_min

)

[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 127 of file multi_postlist.cc.

References Assert, at_end(), currdoc, finished, LOGCALL, LOGLINE, multiplier, postlists, and RETURN.

PositionList * MultiPostList::open_position_list

(

)

const [virtual]

Read the position list for the term in the current document and return a pointer to it (not owned by the PostList).

The default implementation throws Xapian::UnimplementedError.

Reimplemented from Xapian::PostingIterator::Internal.

Definition at line 121 of file multi_postlist.cc.

References currdoc, multiplier, and postlists.

Xapian::weight MultiPostList::recalc_maxweight

(

)

[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.

Note that this method may be called after the postlist has reached the end. In this situation, the method should return 0.

Implements Xapian::PostingIterator::Internal.

Definition at line 89 of file multi_postlist.cc.

References get_weight().

PostList * MultiPostList::skip_to	(	Xapian::docid	,
		Xapian::weight	w_min
	)			[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 164 of file multi_postlist.cc.

References Assert, at_end(), currdoc, finished, LOGCALL, multiplier, postlists, and RETURN.

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Friends And Related Function Documentation

friend class Xapian::Database [friend]

Definition at line 29 of file multi_postlist.h.

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Member Data Documentation

Xapian::docid MultiPostList::currdoc [private]

Definition at line 36 of file multi_postlist.h.

Referenced by get_docid(), get_doclength(), get_wdf(), next(), open_position_list(), and skip_to().

bool MultiPostList::finished [private]

Definition at line 35 of file multi_postlist.h.

Referenced by at_end(), next(), and skip_to().

Xapian::doccount MultiPostList::multiplier [private]

Definition at line 38 of file multi_postlist.h.

Referenced by get_doclength(), get_wdf(), MultiPostList(), next(), open_position_list(), and skip_to().

std::vector<LeafPostList *> MultiPostList::postlists [private]

Definition at line 31 of file multi_postlist.h.

Referenced by get_description(), get_doclength(), get_wdf(), next(), open_position_list(), skip_to(), and ~MultiPostList().

const Xapian::Database& MultiPostList::this_db [private]

Definition at line 33 of file multi_postlist.h.

Referenced by get_doclength().

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

• backends/multi/multi_postlist.h
• backends/multi/multi_postlist.cc