SelectPostList Class Reference

A postlist parent class for classes which only return selected docs from a source postlist (e.g. More...

#include <selectpostlist.h>

Inheritance diagram for SelectPostList:

[legend]Collaboration diagram for SelectPostList:


Public Member Functions
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.
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::weight	get_maxweight () const
	Return an upper bound on what get_weight() can return.
Xapian::docid	get_docid () const
	Return the current docid.
Xapian::weight	get_weight () const
	Return the weight contribution for the current position.
Xapian::doclength	get_doclength () const
	Return the length of current document.
Xapian::weight	recalc_maxweight ()
	Recalculate the upper bound on what get_weight() can return.
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).
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).
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.
	SelectPostList (PostList *source_)
	~SelectPostList ()
Protected Member Functions
virtual bool	test_doc ()=0
	Subclasses should override test_doc() with a method which returns true if a document meets the appropriate criterion, false in not.
Protected Attributes
PostList *	source
Private Member Functions
	SelectPostList (const SelectPostList &)
SelectPostList &	operator= (const SelectPostList &)

Detailed Description

A postlist parent class for classes which only return selected docs from a source postlist (e.g.

NEAR and PHRASE)

Definition at line 32 of file selectpostlist.h.

Constructor & Destructor Documentation

SelectPostList::SelectPostList ( const SelectPostList & ) [private]

SelectPostList::SelectPostList ( PostList * source_ ) [inline]

Definition at line 63 of file selectpostlist.h.

SelectPostList::~SelectPostList ( ) [inline]

Definition at line 64 of file selectpostlist.h.

References source.

Member Function Documentation

SelectPostList& SelectPostList::operator= ( const SelectPostList & ) [private]

virtual bool SelectPostList::test_doc ( ) [protected, pure virtual]

Subclasses should override test_doc() with a method which returns true if a document meets the appropriate criterion, false in not.

Implemented in ExactPhrasePostList, NearPostList, and PhrasePostList.

Referenced by next(), and skip_to().

PostList * SelectPostList::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 30 of file selectpostlist.cc.

References Assert, Xapian::PostingIterator::Internal::at_end(), DEBUGCALL, Xapian::PostingIterator::Internal::next(), RETURN, source, and test_doc().

PostList * SelectPostList::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 42 of file selectpostlist.cc.

References Assert, Xapian::PostingIterator::Internal::at_end(), DEBUGCALL, get_docid(), Xapian::PostingIterator::Internal::next(), RETURN, Xapian::PostingIterator::Internal::skip_to(), source, and test_doc().