A PostList which contains no entries. More...

#include <emptypostlist.h>

Inheritance diagram for EmptyPostList:

Collaboration diagram for EmptyPostList:

Public Member Functions
	EmptyPostList ()
	Constructor. More...

Xapian::doccount	get_termfreq_min () const
	Get a lower bound on the number of documents indexed by this term. More...

Xapian::doccount	get_termfreq_max () const
	Get an upper bound on the number of documents indexed by this term. More...

Xapian::doccount	get_termfreq_est () const
	Get an estimate of the number of documents indexed by this term. More...

TermFreqs	get_termfreq_est_using_stats (const Xapian::Weight::Internal &) const
	Get an estimate for the termfreq and reltermfreq, given the stats. More...

double	get_maxweight () const
	Return an upper bound on what get_weight() can return. More...

Xapian::docid	get_docid () const
	Return the current docid. More...

Xapian::termcount	get_doclength () const
	Return the length of current document. More...

Xapian::termcount	get_unique_terms () const
	Return the number of unique terms in the current document. More...

double	get_weight () const
	Return the weight contribution for the current position. More...

bool	at_end () const
	Return true if the current position is past the last entry in this list. More...

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

PostList *	next (double w_min)
	Advance the current position to the next document in the postlist. More...

PostList *	skip_to (Xapian::docid, double w_min)
	Skip forward to the specified docid. More...

std::string	get_description () const
	Return a string description of this object. More...

Public Member Functions inherited from Xapian::PostingIterator::Internal
virtual	~Internal ()
	We have virtual methods and want to be able to delete derived classes using a pointer to the base class, so we need a virtual destructor. More...

virtual Xapian::termcount	get_wdf () const
	Return the wdf for the document at the current position. More...

virtual const std::string *	get_sort_key () const

virtual const std::string *	get_collapse_key () const
	If the collapse key is already known, return it. More...

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). More...

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). More...

virtual Internal *	check (Xapian::docid did, double w_min, bool &valid)
	Check if the specified docid occurs in this postlist. More...

Internal *	next ()
	Advance the current position to the next document in the postlist. More...

Internal *	skip_to (Xapian::docid did)
	Skip forward to the specified docid. More...

virtual Xapian::termcount	count_matching_subqs () const
	Count the number of leaf subqueries which match at the current position. More...

virtual void	gather_position_lists (OrPositionList *orposlist)
	Gather PositionList* objects for a subtree. More...

Public Member Functions inherited from Xapian::Internal::intrusive_base
	intrusive_base ()
	Construct with no references. More...

Private Member Functions
void	operator= (const EmptyPostList &)
	Don't allow assignment. More...

	EmptyPostList (const EmptyPostList &)
	Don't allow copying. More...

Additional Inherited Members
Public Attributes inherited from Xapian::Internal::intrusive_base
unsigned	_refs
	Reference count. More...

Protected Member Functions inherited from Xapian::PostingIterator::Internal
	Internal ()
	Only constructable as a base class for derived classes. More...

Detailed Description

A PostList which contains no entries.

Definition at line 27 of file emptypostlist.h.

Constructor & Destructor Documentation

◆ EmptyPostList() [1/2]

EmptyPostList::EmptyPostList ( const EmptyPostList & )

private

Don't allow copying.

◆ EmptyPostList() [2/2]

EmptyPostList::EmptyPostList ( )

inline

Constructor.

Definition at line 36 of file emptypostlist.h.

References at_end(), get_description(), get_docid(), get_doclength(), get_maxweight(), get_termfreq_est(), get_termfreq_est_using_stats(), get_termfreq_max(), get_termfreq_min(), get_unique_terms(), get_weight(), Xapian::PostingIterator::Internal::next(), recalc_maxweight(), and skip_to().

Member Function Documentation

◆ at_end()

bool EmptyPostList::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 88 of file emptypostlist.cc.

Referenced by EmptyPostList().

◆ get_description()

string EmptyPostList::get_description ( ) const

virtual

Return a string description of this object.

Implements Xapian::PostingIterator::Internal.

Definition at line 112 of file emptypostlist.cc.

Referenced by EmptyPostList().

◆ get_docid()

Xapian::docid EmptyPostList::get_docid ( ) const

virtual

Return the current docid.

Implements Xapian::PostingIterator::Internal.

Definition at line 62 of file emptypostlist.cc.

References Assert.

Referenced by EmptyPostList(), get_doclength(), and get_unique_terms().

◆ get_doclength()

Xapian::termcount EmptyPostList::get_doclength ( ) const

virtual

Return the length of current document.

Implements Xapian::PostingIterator::Internal.

Definition at line 69 of file emptypostlist.cc.

References get_docid().

Referenced by EmptyPostList().

◆ get_maxweight()

double EmptyPostList::get_maxweight ( ) const

virtual

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

Implements Xapian::PostingIterator::Internal.

Definition at line 56 of file emptypostlist.cc.

Referenced by EmptyPostList(), and recalc_maxweight().

◆ get_termfreq_est()

Xapian::doccount EmptyPostList::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 42 of file emptypostlist.cc.

Referenced by EmptyPostList().

◆ get_termfreq_est_using_stats()

TermFreqs EmptyPostList::get_termfreq_est_using_stats ( const Xapian::Weight::Internal & stats ) const

virtual

Get an estimate for the termfreq and reltermfreq, given the stats.

The frequencies may be for a combination of databases, or for just the relevant documents, so the results need not lie in the bounds given by get_termfreq_min() and get_termfreq_max().

Reimplemented from Xapian::PostingIterator::Internal.

Definition at line 50 of file emptypostlist.cc.

Referenced by EmptyPostList().

◆ get_termfreq_max()

Xapian::doccount EmptyPostList::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 36 of file emptypostlist.cc.

Referenced by EmptyPostList().

◆ get_termfreq_min()

Xapian::doccount EmptyPostList::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 30 of file emptypostlist.cc.

Referenced by EmptyPostList().

◆ get_unique_terms()

Xapian::termcount EmptyPostList::get_unique_terms ( ) const

virtual

Return the number of unique terms in the current document.

Implements Xapian::PostingIterator::Internal.

Definition at line 75 of file emptypostlist.cc.

References get_docid().

Referenced by EmptyPostList().

◆ get_weight()

double EmptyPostList::get_weight ( ) const

virtual

Return the weight contribution for the current position.

Implements Xapian::PostingIterator::Internal.

Definition at line 81 of file emptypostlist.cc.

References Assert.

Referenced by EmptyPostList().

◆ next()

PostList * EmptyPostList::next ( double 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(), skip_to() or check() 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 100 of file emptypostlist.cc.

◆ operator=()

void EmptyPostList::operator= ( const EmptyPostList & )

private

Don't allow assignment.

◆ recalc_maxweight()

double EmptyPostList::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 94 of file emptypostlist.cc.

References get_maxweight().

Referenced by EmptyPostList().

◆ skip_to()

PostList * EmptyPostList::skip_to	(	Xapian::docid	did,
		double	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 106 of file emptypostlist.cc.

Referenced by EmptyPostList().

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

api/emptypostlist.h
api/emptypostlist.cc

Public Member Functions

Private Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ EmptyPostList() [1/2]

◆ EmptyPostList() [2/2]

Member Function Documentation

◆ at_end()

◆ get_description()

◆ get_docid()

◆ get_doclength()

◆ get_maxweight()

◆ get_termfreq_est()

◆ get_termfreq_est_using_stats()

◆ get_termfreq_max()

◆ get_termfreq_min()

◆ get_unique_terms()

◆ get_weight()

◆ next()

◆ operator=()

◆ recalc_maxweight()

◆ skip_to()