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

Implements search over a single IndexReader. More...

#include <IndexSearcher.h>

+ Inheritance diagram for Lucene::IndexSearcher:
+ Collaboration diagram for Lucene::IndexSearcher:

Public Member Functions

 IndexSearcher (const DirectoryPtr &path, bool readOnly=true)
 Creates a searcher searching the index in the named directory. You should pass readOnly = true, since it gives much better concurrent performance, unless you intend to do write operations (delete documents or change norms) with the underlying IndexReader. More...
 
 IndexSearcher (const IndexReaderPtr &reader)
 Creates a searcher searching the provided index. More...
 
 IndexSearcher (const IndexReaderPtr &reader, Collection< IndexReaderPtr > subReaders, Collection< int32_t > docStarts)
 Directly specify the reader, subReaders and their docID starts. More...
 
virtual ~IndexSearcher ()
 
virtual String getClassName ()
 
boost::shared_ptr< IndexSearchershared_from_this ()
 
IndexReaderPtr getIndexReader ()
 Return the IndexReader this searches. More...
 
virtual void close ()
 Note that the underlying IndexReader is not closed, if IndexSearcher was constructed with IndexSearcher(const IndexReaderPtr& reader). If the IndexReader was supplied implicitly by specifying a directory, then the IndexReader gets closed. More...
 
virtual int32_t docFreq (const TermPtr &term)
 Returns the number of documents containing term. More...
 
virtual DocumentPtr doc (int32_t n)
 Returns the stored fields of document i. More...
 
virtual DocumentPtr doc (int32_t n, const FieldSelectorPtr &fieldSelector)
 Get the Document at the n'th position. The FieldSelector may be used to determine what Fields to load and how they should be loaded. More...
 
virtual int32_t maxDoc ()
 Returns one greater than the largest possible document number. More...
 
virtual TopDocsPtr search (const WeightPtr &weight, const FilterPtr &filter, int32_t n)
 Low-level search implementation. Finds the top n hits for query, applying filter if non-null. Applications should usually call Searcher#search(QueryPtr, int32_t) or Searcher#search(QueryPtr, FilterPtr, int32_t) instead. More...
 
virtual TopFieldDocsPtr search (const WeightPtr &weight, const FilterPtr &filter, int32_t n, const SortPtr &sort)
 Low-level search implementation with arbitrary sorting. Finds the top n hits for query, applying filter if non-null, and sorting the hits by the criteria in sort. More...
 
virtual TopFieldDocsPtr search (const WeightPtr &weight, const FilterPtr &filter, int32_t n, const SortPtr &sort, bool fillFields)
 Just like search(WeightPtr, FilterPtr, int32_t, SortPtr), but you choose whether or not the fields in the returned FieldDoc instances should be set by specifying fillFields. More...
 
virtual void search (const WeightPtr &weight, const FilterPtr &filter, const CollectorPtr &results)
 Lower-level search API. More...
 
virtual QueryPtr rewrite (const QueryPtr &query)
 Called to re-write queries into primitive queries. More...
 
virtual ExplanationPtr explain (const WeightPtr &weight, int32_t doc)
 Low-level implementation method. Returns an Explanation that describes how doc scored against weight. More...
 
virtual void setDefaultFieldSortScoring (bool doTrackScores, bool doMaxScore)
 By default, no scores are computed when sorting by field (using FilterPtr, int32_t, SortPtr)). You can change that, per IndexSearcher instance, by calling this method. Note that this will incur a CPU cost. More...
 
- Public Member Functions inherited from Lucene::Searcher
 Searcher ()
 
virtual ~Searcher ()
 
boost::shared_ptr< Searchershared_from_this ()
 
virtual TopFieldDocsPtr search (const QueryPtr &query, const FilterPtr &filter, int32_t n, const SortPtr &sort)
 Search implementation with arbitrary sorting. Finds the top n hits for query, applying filter if non-null, and sorting the hits by the criteria in sort. More...
 
virtual void search (const QueryPtr &query, const CollectorPtr &results)
 Lower-level search API. More...
 
virtual void search (const QueryPtr &query, const FilterPtr &filter, const CollectorPtr &results)
 Lower-level search API. More...
 
virtual TopDocsPtr search (const QueryPtr &query, const FilterPtr &filter, int32_t n)
 Finds the top n hits for query, applying filter if non-null. More...
 
virtual TopDocsPtr search (const QueryPtr &query, int32_t n)
 Finds the top n hits for query. More...
 
virtual ExplanationPtr explain (const QueryPtr &query, int32_t doc)
 Returns an Explanation that describes how doc scored against query. More...
 
virtual void setSimilarity (const SimilarityPtr &similarity)
 Set the Similarity implementation used by this Searcher. More...
 
virtual SimilarityPtr getSimilarity ()
 Return the Similarity implementation used by this Searcher. More...
 
virtual Collection< int32_t > docFreqs (Collection< TermPtr > terms)
 For each term in the terms array, calculates the number of documents containing term. Returns an array with these document frequencies. Used to minimize number of remote calls. More...
 
- Public Member Functions inherited from Lucene::Searchable
virtual ~Searchable ()
 
- 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. More...
 
virtual LuceneObjectPtr clone (const LuceneObjectPtr &other=LuceneObjectPtr())
 Return clone of this object. More...
 
virtual int32_t hashCode ()
 Return hash code for this object. More...
 
virtual bool equals (const LuceneObjectPtr &other)
 Return whether two objects are equal. More...
 
virtual int32_t compareTo (const LuceneObjectPtr &other)
 Compare two objects. More...
 
virtual String toString ()
 Returns a string representation of the object. More...
 
- Public Member Functions inherited from Lucene::LuceneSync
virtual ~LuceneSync ()
 
virtual SynchronizePtr getSync ()
 Return this object synchronize lock. More...
 
virtual LuceneSignalPtr getSignal ()
 Return this object signal. More...
 
virtual void lock (int32_t timeout=0)
 Lock this object using an optional timeout. More...
 
virtual void unlock ()
 Unlock this object. More...
 
virtual bool holdsLock ()
 Returns true if this object is currently locked by current thread. More...
 
virtual void wait (int32_t timeout=0)
 Wait for signal using an optional timeout. More...
 
virtual void notifyAll ()
 Notify all threads waiting for signal. More...
 

Static Public Member Functions

static String _getClassName ()
 
- Static Public Member Functions inherited from Lucene::Searcher
static String _getClassName ()
 
- Static Public Member Functions inherited from Lucene::Searchable
static String _getClassName ()
 

Data Fields

IndexReaderPtr reader
 

Protected Member Functions

void ConstructSearcher (const IndexReaderPtr &reader, bool closeReader)
 
void gatherSubReaders (Collection< IndexReaderPtr > allSubReaders, const IndexReaderPtr &reader)
 
void searchWithFilter (const IndexReaderPtr &reader, const WeightPtr &weight, const FilterPtr &filter, const CollectorPtr &collector)
 
- Protected Member Functions inherited from Lucene::Searcher
virtual WeightPtr createWeight (const QueryPtr &query)
 Creates a weight for query. More...
 
- Protected Member Functions inherited from Lucene::LuceneObject
 LuceneObject ()
 

Protected Attributes

bool closeReader
 
Collection< IndexReaderPtrsubReaders
 
Collection< int32_t > docStarts
 
bool fieldSortDoTrackScores
 
bool fieldSortDoMaxScore
 
- Protected Attributes inherited from Lucene::Searcher
SimilarityPtr similarity
 The Similarity implementation used by this searcher. More...
 
- Protected Attributes inherited from Lucene::LuceneSync
SynchronizePtr objectLock
 
LuceneSignalPtr objectSignal
 

Detailed Description

Implements search over a single IndexReader.

Applications usually need only call the inherited search(QueryPtr, int32_t) or search(QueryPtr, FilterPtr, int32_t) methods. For performance reasons it is recommended to open only one IndexSearcher and use it for all of your searches.

NOTE: IndexSearcher instances are completely thread safe, meaning multiple threads can call any of its methods, concurrently. If your application requires external synchronization, you should not synchronize on the IndexSearcher instance; use your own (non-Lucene) objects instead.

Constructor & Destructor Documentation

Lucene::IndexSearcher::IndexSearcher ( const DirectoryPtr path,
bool  readOnly = true 
)

Creates a searcher searching the index in the named directory. You should pass readOnly = true, since it gives much better concurrent performance, unless you intend to do write operations (delete documents or change norms) with the underlying IndexReader.

Parameters
pathDirectory where IndexReader will be opened
readOnlyIf true, the underlying IndexReader will be opened readOnly
Lucene::IndexSearcher::IndexSearcher ( const IndexReaderPtr reader)

Creates a searcher searching the provided index.

Lucene::IndexSearcher::IndexSearcher ( const IndexReaderPtr reader,
Collection< IndexReaderPtr subReaders,
Collection< int32_t >  docStarts 
)

Directly specify the reader, subReaders and their docID starts.

virtual Lucene::IndexSearcher::~IndexSearcher ( )
virtual

Member Function Documentation

static String Lucene::IndexSearcher::_getClassName ( )
inlinestatic
virtual void Lucene::IndexSearcher::close ( )
virtual

Note that the underlying IndexReader is not closed, if IndexSearcher was constructed with IndexSearcher(const IndexReaderPtr& reader). If the IndexReader was supplied implicitly by specifying a directory, then the IndexReader gets closed.

Implements Lucene::Searcher.

void Lucene::IndexSearcher::ConstructSearcher ( const IndexReaderPtr reader,
bool  closeReader 
)
protected
virtual DocumentPtr Lucene::IndexSearcher::doc ( int32_t  n)
virtual

Returns the stored fields of document i.

See also
IndexReader::document(int32_t)

Implements Lucene::Searcher.

virtual DocumentPtr Lucene::IndexSearcher::doc ( int32_t  n,
const FieldSelectorPtr fieldSelector 
)
virtual

Get the Document at the n'th position. The FieldSelector may be used to determine what Fields to load and how they should be loaded.

NOTE: If the underlying Reader (more specifically, the underlying FieldsReader) is closed before the lazy Field is loaded an exception may be thrown. If you want the value of a lazy Field to be available after closing you must explicitly load it or fetch the Document again with a new loader.

Parameters
nGet the document at the n'th position
fieldSelectorThe FieldSelector to use to determine what Fields should be loaded on the Document. May be null, in which case all Fields will be loaded.
Returns
The stored fields of the Document at the n'th position
See also
IndexReader::document(int32_t, FieldSelectorPtr)
Fieldable
FieldSelector
SetBasedFieldSelector
LoadFirstFieldSelector

Implements Lucene::Searcher.

virtual int32_t Lucene::IndexSearcher::docFreq ( const TermPtr term)
virtual

Returns the number of documents containing term.

See also
IndexReader::docFreq(TermPtr)

Implements Lucene::Searcher.

virtual ExplanationPtr Lucene::IndexSearcher::explain ( const WeightPtr weight,
int32_t  doc 
)
virtual

Low-level implementation method. Returns an Explanation that describes how doc scored against weight.

This is intended to be used in developing Similarity implementations, and for good performance, should not be displayed with every hit. Computing an explanation is as expensive as executing the query over the entire index.

Applications should call Searcher#explain(QueryPtr, int32_t).

Implements Lucene::Searcher.

void Lucene::IndexSearcher::gatherSubReaders ( Collection< IndexReaderPtr allSubReaders,
const IndexReaderPtr reader 
)
protected
virtual String Lucene::IndexSearcher::getClassName ( )
inlinevirtual

Reimplemented from Lucene::Searcher.

IndexReaderPtr Lucene::IndexSearcher::getIndexReader ( )

Return the IndexReader this searches.

virtual int32_t Lucene::IndexSearcher::maxDoc ( )
virtual

Returns one greater than the largest possible document number.

See also
IndexReader::maxDoc()

Implements Lucene::Searcher.

virtual QueryPtr Lucene::IndexSearcher::rewrite ( const QueryPtr query)
virtual

Called to re-write queries into primitive queries.

Implements Lucene::Searcher.

virtual TopDocsPtr Lucene::IndexSearcher::search ( const WeightPtr weight,
const FilterPtr filter,
int32_t  n 
)
virtual

Low-level search implementation. Finds the top n hits for query, applying filter if non-null. Applications should usually call Searcher#search(QueryPtr, int32_t) or Searcher#search(QueryPtr, FilterPtr, int32_t) instead.

Implements Lucene::Searcher.

virtual TopFieldDocsPtr Lucene::IndexSearcher::search ( const WeightPtr weight,
const FilterPtr filter,
int32_t  n,
const SortPtr sort 
)
virtual

Low-level search implementation with arbitrary sorting. Finds the top n hits for query, applying filter if non-null, and sorting the hits by the criteria in sort.

Applications should usually call Searcher#search(QueryPtr, FilterPtr, int32_t, SortPtr) instead.

Implements Lucene::Searcher.

virtual TopFieldDocsPtr Lucene::IndexSearcher::search ( const WeightPtr weight,
const FilterPtr filter,
int32_t  n,
const SortPtr sort,
bool  fillFields 
)
virtual

Just like search(WeightPtr, FilterPtr, int32_t, SortPtr), but you choose whether or not the fields in the returned FieldDoc instances should be set by specifying fillFields.

NOTE: this does not compute scores by default. If you need scores, create a TopFieldCollector instance by calling TopFieldCollector#create and then pass that to FilterPtr, CollectorPtr).

virtual void Lucene::IndexSearcher::search ( const WeightPtr weight,
const FilterPtr filter,
const CollectorPtr collector 
)
virtual

Lower-level search API.

Collector#collect(int32_t) is called for every document. Collector-based access to remote indexes is discouraged.

Applications should only use this if they need all of the matching documents. The high-level search API (Searcher#search(QueryPtr, int32_t)) is usually more efficient, as it skips non-high-scoring hits.

Parameters
weightTo match documents
filterIf non-null, used to permit documents to be collected.
collectorTo receive hits

Implements Lucene::Searcher.

void Lucene::IndexSearcher::searchWithFilter ( const IndexReaderPtr reader,
const WeightPtr weight,
const FilterPtr filter,
const CollectorPtr collector 
)
protected
virtual void Lucene::IndexSearcher::setDefaultFieldSortScoring ( bool  doTrackScores,
bool  doMaxScore 
)
virtual

By default, no scores are computed when sorting by field (using FilterPtr, int32_t, SortPtr)). You can change that, per IndexSearcher instance, by calling this method. Note that this will incur a CPU cost.

Parameters
doTrackScoresIf true, then scores are returned for every matching document in TopFieldDocs.
doMaxScoreIf true, then the max score for all matching docs is computed.
boost::shared_ptr< IndexSearcher > Lucene::IndexSearcher::shared_from_this ( )
inline

Field Documentation

bool Lucene::IndexSearcher::closeReader
protected
Collection<int32_t> Lucene::IndexSearcher::docStarts
protected
bool Lucene::IndexSearcher::fieldSortDoMaxScore
protected
bool Lucene::IndexSearcher::fieldSortDoTrackScores
protected
IndexReaderPtr Lucene::IndexSearcher::reader
Collection<IndexReaderPtr> Lucene::IndexSearcher::subReaders
protected

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

clucene.sourceforge.net