org.apache.lucene.search

Class Query

Implemented Interfaces:
Cloneable, java.io.Serializable
Known Direct Subclasses:
BooleanQuery, FilteredQuery, MultiTermQuery, PhrasePrefixQuery, PhraseQuery, PrefixQuery, RangeQuery, SpanQuery, TermQuery

public abstract class Query
extends java.lang.Object
implements java.io.Serializable, Cloneable

The abstract base class for queries.

Instantiable subclasses are:

A parser for queries is contained in:

See Also:
Serialized Form

Method Summary

Object
clone()
Returns a clone of this query.
Query
combine(Query queries)
Expert: called when re-writing queries under MultiSearcher.
protected Weight
createWeight(Searcher searcher)
Expert: Constructs an appropriate Weight implementation for this query.
float
getBoost()
Gets the boost for this clause.
Similarity
getSimilarity(Searcher searcher)
Expert: Returns the Similarity implementation to be used for this query.
static Query
mergeBooleanQueries(Query queries)
Expert: merges the clauses of a set of BooleanQuery's into a single BooleanQuery.
Query
rewrite(IndexReader reader)
Expert: called to re-write queries into primitive queries.
void
setBoost(float b)
Sets the boost for this query clause to b.
String
toString()
Prints a query to a string.
String
toString(String field)
Prints a query to a string, with field as the default field for terms.
Weight
weight(Searcher searcher)
Expert: Constructs an initializes a Weight for a top-level query.

Method Details

clone

public Object clone()
Returns a clone of this query.


combine

public Query combine(Query queries)
Expert: called when re-writing queries under MultiSearcher.

Only implemented by derived queries, with no createWeight(Searcher) implementatation.


createWeight

protected Weight createWeight(Searcher searcher)
Expert: Constructs an appropriate Weight implementation for this query.

Only implemented by primitive queries, which re-write to themselves.


getBoost

public float getBoost()
Gets the boost for this clause. Documents matching this clause will (in addition to the normal weightings) have their score multiplied by b. The boost is 1.0 by default.


getSimilarity

public Similarity getSimilarity(Searcher searcher)
Expert: Returns the Similarity implementation to be used for this query. Subclasses may override this method to specify their own Similarity implementation, perhaps one that delegates through that of the Searcher. By default the Searcher's Similarity implementation is returned.


mergeBooleanQueries

public static Query mergeBooleanQueries(Query queries)
Expert: merges the clauses of a set of BooleanQuery's into a single BooleanQuery.

A utility for use by combine(Query[]) implementations.


rewrite

public Query rewrite(IndexReader reader)
            throws IOException
Expert: called to re-write queries into primitive queries.


setBoost

public void setBoost(float b)
Sets the boost for this query clause to b. Documents matching this clause will (in addition to the normal weightings) have their score multiplied by b.


toString

public String toString()
Prints a query to a string.


toString

public String toString(String field)
Prints a query to a string, with field as the default field for terms.

The representation used is one that is readable by QueryParser (although, if the query was created by the parser, the printed representation may not be exactly what was parsed).


weight

public Weight weight(Searcher searcher)
            throws IOException
Expert: Constructs an initializes a Weight for a top-level query.


Copyright © 2000-2005 Apache Software Foundation. All Rights Reserved.