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Public Member Functions | Static Public Member Functions | Data Fields | Protected Member Functions
Lucene::TopScoreDocCollector Class Reference

A Collector implementation that collects the top-scoring hits, returning them as a TopDocs. This is used by IndexSearcher to implement TopDocs-based search. Hits are sorted by score descending and then (when the scores are tied) docID ascending. When you create an instance of this collector you should know in advance whether documents are going to be collected in doc Id order or not. More...

#include <TopScoreDocCollector.h>

+ Inheritance diagram for Lucene::TopScoreDocCollector:

Public Member Functions

 TopScoreDocCollector (int32_t numHits)
 
virtual ~TopScoreDocCollector ()
 
virtual String getClassName ()
 
boost::shared_ptr< TopScoreDocCollectorshared_from_this ()
 
virtual void setNextReader (const IndexReaderPtr &reader, int32_t docBase)
 Called before collecting from each IndexReader. All doc ids in collect(int32_t) will correspond to reader. Add docBase to the current IndexReaders internal document id to re-base ids in collect(int32_t).
 
virtual void setScorer (const ScorerPtr &scorer)
 Called before successive calls to collect(int32_t). Implementations that need the score of the current document (passed-in to collect(int32_t)), should save the passed-in Scorer and call scorer.score() when needed.
 
- Public Member Functions inherited from Lucene::TopDocsCollector
 TopDocsCollector (const HitQueueBasePtr &pq)
 
virtual ~TopDocsCollector ()
 
boost::shared_ptr< TopDocsCollectorshared_from_this ()
 
virtual int32_t getTotalHits ()
 The total number of documents that matched this query.
 
virtual TopDocsPtr topDocs ()
 Returns the top docs that were collected by this collector.
 
virtual TopDocsPtr topDocs (int32_t start)
 Returns the documents in the range [start .. pq.size()) that were collected by this collector. Note that if start >= pq.size(), an empty TopDocs is returned.
 
virtual TopDocsPtr topDocs (int32_t start, int32_t howMany)
 Returns the documents in the rage [start .. start + howMany) that were collected by this collector. Note that if start >= pq.size(), an empty TopDocs is returned, and if pq.size() - start < howMany, then only the available documents in [start .. pq.size()) are returned.
 
- Public Member Functions inherited from Lucene::Collector
virtual ~Collector ()
 
boost::shared_ptr< Collectorshared_from_this ()
 
virtual void collect (int32_t doc)=0
 Called once for every document matching a query, with the unbased document number.
 
virtual bool acceptsDocsOutOfOrder ()=0
 Return true if this collector does not require the matching docIDs to be delivered in int sort order (smallest to largest) to collect.
 
- Public Member Functions inherited from Lucene::LuceneObject
virtual ~LuceneObject ()
 
virtual void initialize ()
 Called directly after instantiation to create objects that depend on this object being fully constructed.
 
virtual LuceneObjectPtr clone (const LuceneObjectPtr &other=LuceneObjectPtr())
 Return clone of this object.
 
virtual int32_t hashCode ()
 Return hash code for this object.
 
virtual bool equals (const LuceneObjectPtr &other)
 Return whether two objects are equal.
 
virtual int32_t compareTo (const LuceneObjectPtr &other)
 Compare two objects.
 
virtual String toString ()
 Returns a string representation of the object.
 
- Public Member Functions inherited from Lucene::LuceneSync
virtual ~LuceneSync ()
 
virtual SynchronizePtr getSync ()
 Return this object synchronize lock.
 
virtual LuceneSignalPtr getSignal ()
 Return this object signal.
 
virtual void lock (int32_t timeout=0)
 Lock this object using an optional timeout.
 
virtual void unlock ()
 Unlock this object.
 
virtual bool holdsLock ()
 Returns true if this object is currently locked by current thread.
 
virtual void wait (int32_t timeout=0)
 Wait for signal using an optional timeout.
 
virtual void notifyAll ()
 Notify all threads waiting for signal.
 

Static Public Member Functions

static String _getClassName ()
 
static TopScoreDocCollectorPtr create (int32_t numHits, bool docsScoredInOrder)
 Creates a new TopScoreDocCollector given the number of hits to collect and whether documents are scored in order by the input Scorer to setScorer(ScorerPtr).
 
- Static Public Member Functions inherited from Lucene::TopDocsCollector
static String _getClassName ()
 
- Static Public Member Functions inherited from Lucene::Collector
static String _getClassName ()
 

Data Fields

INTERNAL : ScoreDocPtr pqTop
 
int32_t docBase
 
ScorerWeakPtr _scorer
 
Scorer__scorer
 

Protected Member Functions

virtual TopDocsPtr newTopDocs (Collection< ScoreDocPtr > results, int32_t start)
 Returns a TopDocs instance containing the given results. If results is null it means there are no results to return, either because there were 0 calls to collect() or because the arguments to topDocs were invalid.
 
- Protected Member Functions inherited from Lucene::TopDocsCollector
virtual void populateResults (Collection< ScoreDocPtr > results, int32_t howMany)
 Populates the results array with the ScoreDoc instances. This can be overridden in case a different ScoreDoc type should be returned.
 
- Protected Member Functions inherited from Lucene::LuceneObject
 LuceneObject ()
 

Additional Inherited Members

- Static Protected Member Functions inherited from Lucene::TopDocsCollector
static TopDocsPtr EMPTY_TOPDOCS ()
 This is used in case topDocs() is called with illegal parameters, or there simply aren't (enough) results.
 
- Protected Attributes inherited from Lucene::TopDocsCollector
HitQueueBasePtr pq
 The priority queue which holds the top documents. Note that different implementations of PriorityQueue give different meaning to 'top documents'. HitQueue for example aggregates the top scoring documents, while other PQ implementations may hold documents sorted by other criteria.
 
int32_t totalHits
 The total number of documents that the collector encountered.
 
- Protected Attributes inherited from Lucene::LuceneSync
SynchronizePtr objectLock
 
LuceneSignalPtr objectSignal
 

Detailed Description

A Collector implementation that collects the top-scoring hits, returning them as a TopDocs. This is used by IndexSearcher to implement TopDocs-based search. Hits are sorted by score descending and then (when the scores are tied) docID ascending. When you create an instance of this collector you should know in advance whether documents are going to be collected in doc Id order or not.

NOTE: The values Nan, NEGATIVE_INFINITY and POSITIVE_INFINITY are not valid scores. This collector will not properly collect hits with such scores.

Constructor & Destructor Documentation

◆ TopScoreDocCollector()

Lucene::TopScoreDocCollector::TopScoreDocCollector ( int32_t  numHits)

◆ ~TopScoreDocCollector()

virtual Lucene::TopScoreDocCollector::~TopScoreDocCollector ( )
virtual

Member Function Documentation

◆ _getClassName()

static String Lucene::TopScoreDocCollector::_getClassName ( )
inlinestatic

◆ create()

static TopScoreDocCollectorPtr Lucene::TopScoreDocCollector::create ( int32_t  numHits,
bool  docsScoredInOrder 
)
static

Creates a new TopScoreDocCollector given the number of hits to collect and whether documents are scored in order by the input Scorer to setScorer(ScorerPtr).

NOTE: The instances returned by this method pre-allocate a full array of length numHits.

◆ getClassName()

virtual String Lucene::TopScoreDocCollector::getClassName ( )
inlinevirtual

Reimplemented from Lucene::TopDocsCollector.

◆ newTopDocs()

virtual TopDocsPtr Lucene::TopScoreDocCollector::newTopDocs ( Collection< ScoreDocPtr results,
int32_t  start 
)
protectedvirtual

Returns a TopDocs instance containing the given results. If results is null it means there are no results to return, either because there were 0 calls to collect() or because the arguments to topDocs were invalid.

Reimplemented from Lucene::TopDocsCollector.

◆ setNextReader()

virtual void Lucene::TopScoreDocCollector::setNextReader ( const IndexReaderPtr reader,
int32_t  docBase 
)
virtual

Called before collecting from each IndexReader. All doc ids in collect(int32_t) will correspond to reader. Add docBase to the current IndexReaders internal document id to re-base ids in collect(int32_t).

Parameters
readernext IndexReader
docBase

Implements Lucene::Collector.

◆ setScorer()

virtual void Lucene::TopScoreDocCollector::setScorer ( const ScorerPtr scorer)
virtual

Called before successive calls to collect(int32_t). Implementations that need the score of the current document (passed-in to collect(int32_t)), should save the passed-in Scorer and call scorer.score() when needed.

Implements Lucene::Collector.

◆ shared_from_this()

boost::shared_ptr< TopScoreDocCollector > Lucene::TopScoreDocCollector::shared_from_this ( )
inline

Field Documentation

◆ __pad0__

INTERNAL Lucene::TopScoreDocCollector::__pad0__

◆ __scorer

Scorer* Lucene::TopScoreDocCollector::__scorer

◆ _scorer

ScorerWeakPtr Lucene::TopScoreDocCollector::_scorer

◆ docBase

int32_t Lucene::TopScoreDocCollector::docBase

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

clucene.sourceforge.net