gate.creole.annic.apache.lucene.search
Class IndexSearcher

java.lang.Object
  gate.creole.annic.apache.lucene.search.Searcher
      gate.creole.annic.apache.lucene.search.IndexSearcher

All Implemented Interfaces:

Searchable, Remote

Direct Known Subclasses:

LuceneIndexSearcher

public class IndexSearcher
extends Searcher

Implements search over a single IndexReader.

Applications usually need only call the inherited Searcher.search(Query) or Searcher.search(Query,Filter) methods.

Field Summary

private boolean	closeReader
private ArrayList<Integer>	documentNumbers document numbers
private ArrayList	firstTermPositions Each Integer value in this list is an index of first annotation of the pattern that matches with the user query.
private ArrayList<Integer>	frequencies Each terms has a frequency.
private ArrayList<Integer>	patternLengths Stores how long each pattern is (in terms of number of annotations).
private ArrayList<Integer>	queryType Each pattern is a result of either simple or a boolean query.
(package private) IndexReader	reader

Constructor Summary

	IndexSearcher(Directory directory) Creates a searcher searching the index in the provided directory.
	IndexSearcher(IndexReader r) Creates a searcher searching the provided index.
private	IndexSearcher(IndexReader r, boolean closeReader)
	IndexSearcher(String path) Creates a searcher searching the index in the named directory.

Method Summary

void	close() Note that the underlying IndexReader is not closed, if IndexSearcher was constructed with IndexSearcher(IndexReader r).
Document	doc(int i) Expert: Returns the stored fields of document i.
int	docFreq(Term term) Expert: Returns the number of documents containing term.
Explanation	explain(Query query, int doc) Returns an Explanation that describes how doc scored against query.
ArrayList[]	getFirstTermPositions() Returns an array of arrayLists where the first list contains document numbers, second list contains first term positions, third list contains the pattern lengths and the fourth one contains the query type for each pattern.
void	initializeTermPositions() Initializes all local variables
int	maxDoc() Expert: Returns one greater than the largest possible document number.
Query	rewrite(Query original) Expert: called to re-write queries into primitive queries.
void	search(Query query, Filter filter, HitCollector results) Lower-level search API.
TopDocs	search(Query query, Filter filter, int nDocs) Expert: Low-level search implementation.
TopFieldDocs	search(Query query, Filter filter, int nDocs, Sort sort) Expert: Low-level search implementation with arbitrary sorting.
void	setFirstTermPositions(int qType, int doc, ArrayList positions, int patternLength, int frequency) Sets the firstTermPositions.

Methods inherited from class gate.creole.annic.apache.lucene.search.Searcher

getSimilarity, search, search, search, search, search, setSimilarity

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

reader

IndexReader reader

closeReader

private boolean closeReader

queryType

private ArrayList<Integer> queryType

Each pattern is a result of either simple or a boolean query. The type number indicates if the query used to retrieve that pattern was simple or boolean.

frequencies

private ArrayList<Integer> frequencies

Each terms has a frequency.

firstTermPositions

private ArrayList firstTermPositions

Each Integer value in this list is an index of first annotation of the pattern that matches with the user query.

documentNumbers

private ArrayList<Integer> documentNumbers

document numbers

patternLengths

private ArrayList<Integer> patternLengths

Stores how long each pattern is (in terms of number of annotations).

Constructor Detail

IndexSearcher

public IndexSearcher(String path)
              throws IOException

Creates a searcher searching the index in the named directory.

Throws:

IOException

IndexSearcher

public IndexSearcher(Directory directory)
              throws IOException

Creates a searcher searching the index in the provided directory.

Throws:

IOException

IndexSearcher

public IndexSearcher(IndexReader r)

Creates a searcher searching the provided index.

IndexSearcher

private IndexSearcher(IndexReader r,
                      boolean closeReader)

Method Detail

close

public void close()
           throws IOException

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

Throws:

IOException

docFreq

public int docFreq(Term term)
            throws IOException

Description copied from interface: Searchable

Expert: Returns the number of documents containing term. Called by search code to compute term weights.

Throws:

IOException

See Also:

IndexReader.docFreq(Term).

doc

public Document doc(int i)
             throws IOException

Description copied from interface: Searchable

Expert: Returns the stored fields of document i. Called by HitCollector implementations.

Throws:

IOException

See Also:

IndexReader.document(int).

maxDoc

public int maxDoc()
           throws IOException

Description copied from interface: Searchable

Expert: Returns one greater than the largest possible document number. Called by search code to compute term weights.

Throws:

IOException

See Also:

IndexReader.maxDoc().

search

public TopDocs search(Query query,
                      Filter filter,
                      int nDocs)
               throws IOException

Description copied from interface: Searchable

Expert: Low-level search implementation. Finds the top n hits for query, applying filter if non-null.

Called by Hits.

Applications should usually call Searcher.search(Query) or Searcher.search(Query,Filter) instead.

Throws:

IOException

search

public TopFieldDocs search(Query query,
                           Filter filter,
                           int nDocs,
                           Sort sort)
                    throws IOException

Description copied from interface: Searchable

Expert: 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(Query,Filter,Sort) instead.

Throws:

IOException

search

public void search(Query query,
                   Filter filter,
                   HitCollector results)
            throws IOException

Description copied from interface: Searchable

Lower-level search API.

HitCollector.collect(int,float) is called for every non-zero scoring document.

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

Parameters:

query - to match documents

filter - if non-null, a bitset used to eliminate some documents

results - to receive hits

Throws:

IOException

rewrite

public Query rewrite(Query original)
              throws IOException

Description copied from interface: Searchable

Expert: called to re-write queries into primitive queries.

Throws:

IOException

explain

public Explanation explain(Query query,
                           int doc)
                    throws IOException

Description copied from interface: Searchable

Returns an Explanation that describes how doc scored against query.

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.

Throws:

IOException

setFirstTermPositions

public void setFirstTermPositions(int qType,
                                  int doc,
                                  ArrayList positions,
                                  int patternLength,
                                  int frequency)

Sets the firstTermPositions.

Parameters:

qType -

doc -

positions -

patternLength -

initializeTermPositions

public void initializeTermPositions()

Initializes all local variables

getFirstTermPositions

public ArrayList[] getFirstTermPositions()

Returns an array of arrayLists where the first list contains document numbers, second list contains first term positions, third list contains the pattern lengths and the fourth one contains the query type for each pattern.

Returns: