Package org.elasticsearch.common.lucene.search.function

Class FunctionScoreQuery

java.lang.Object

org.apache.lucene.search.Query

org.elasticsearch.common.lucene.search.function.FunctionScoreQuery

public class FunctionScoreQuery
extends Query

A query that allows for a pluggable boost function / filter. If it matches the filter, it will be boosted by the formula.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	FunctionScoreQuery.FilterScoreFunction
static class	FunctionScoreQuery.ScoreMode

Field Summary

Fields

Modifier and Type	Field	Description
static float	DEFAULT_MAX_BOOST

Constructor Summary

Constructors

Constructor	Description
FunctionScoreQuery(Query subQuery, Float minScore, float maxBoost)	Creates a FunctionScoreQuery without function.
FunctionScoreQuery(Query subQuery, FunctionScoreQuery.ScoreMode scoreMode, ScoreFunction[] functions, CombineFunction combineFunction, Float minScore, float maxBoost)	Creates a FunctionScoreQuery with multiple score functions
FunctionScoreQuery(Query subQuery, ScoreFunction function)	Creates a FunctionScoreQuery with a single ScoreFunction
FunctionScoreQuery(Query subQuery, ScoreFunction function, CombineFunction combineFunction, Float minScore, float maxBoost)	Creates a FunctionScoreQuery with a single function

Method Summary

Modifier and Type	Method	Description
Weight	createWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost)	Expert: Constructs an appropriate Weight implementation for this query.
boolean	equals(Object o)	Override and implement query instance equivalence properly in a subclass.
CombineFunction	getCombineFunction()
ScoreFunction[]	getFunctions()
Float	getMinScore()
Query	getSubQuery()
int	hashCode()	Override and implement query hash code properly in a subclass.
Query	rewrite(IndexReader reader)	Expert: called to re-write queries into primitive queries.
String	toString(String field)	Prints a query to a string, with field assumed to be the default field and omitted.
void	visit(QueryVisitor visitor)	Recurse through the query tree, visiting any child queries

Methods inherited from class org.apache.lucene.search.Query

classHash, sameClassAs, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

DEFAULT_MAX_BOOST

public static final float DEFAULT_MAX_BOOST

See Also:

Constant Field Values

Constructor Detail

FunctionScoreQuery

public FunctionScoreQuery(Query subQuery,
                          Float minScore,
                          float maxBoost)

Creates a FunctionScoreQuery without function.

Parameters:

subQuery - The query to match.

minScore - The minimum score to consider a document.

maxBoost - The maximum applicable boost.

FunctionScoreQuery

public FunctionScoreQuery(Query subQuery,
                          ScoreFunction function)

Creates a FunctionScoreQuery with a single ScoreFunction

Parameters:

subQuery - The query to match.

function - The ScoreFunction to apply.

FunctionScoreQuery

public FunctionScoreQuery(Query subQuery,
                          ScoreFunction function,
                          CombineFunction combineFunction,
                          Float minScore,
                          float maxBoost)

Creates a FunctionScoreQuery with a single function

Parameters:

subQuery - The query to match.

function - The ScoreFunction to apply.

combineFunction - Defines how the query and function score should be applied.

minScore - The minimum score to consider a document.

maxBoost - The maximum applicable boost.

FunctionScoreQuery

public FunctionScoreQuery(Query subQuery,
                          FunctionScoreQuery.ScoreMode scoreMode,
                          ScoreFunction[] functions,
                          CombineFunction combineFunction,
                          Float minScore,
                          float maxBoost)

Creates a FunctionScoreQuery with multiple score functions

Parameters:

subQuery - The query to match.

scoreMode - Defines how the different score functions should be combined.

functions - The ScoreFunctions to apply.

combineFunction - Defines how the query and function score should be applied.

minScore - The minimum score to consider a document.

maxBoost - The maximum applicable boost.

Method Detail

getSubQuery

public Query getSubQuery()

getFunctions

public ScoreFunction[] getFunctions()

getMinScore

public Float getMinScore()

getCombineFunction

public CombineFunction getCombineFunction()

visit

public void visit(QueryVisitor visitor)

Description copied from class: Query

Recurse through the query tree, visiting any child queries

Overrides:

visit in class Query

Parameters:

visitor - a QueryVisitor to be called by each query in the tree

rewrite

public Query rewrite(IndexReader reader)
              throws IOException

Description copied from class: Query

Expert: called to re-write queries into primitive queries. For example, a PrefixQuery will be rewritten into a BooleanQuery that consists of TermQuerys.

Overrides:

rewrite in class Query

Throws:

IOException

createWeight

public Weight createWeight(IndexSearcher searcher,
                           ScoreMode scoreMode,
                           float boost)
                    throws IOException

Description copied from class: Query

Expert: Constructs an appropriate Weight implementation for this query.

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

Overrides:

createWeight in class Query

scoreMode - How the produced scorers will be consumed.

boost - The boost that is propagated by the parent queries.

Throws:

IOException

toString

public String toString(String field)

Description copied from class: Query

Prints a query to a string, with field assumed to be the default field and omitted.

Specified by:

toString in class Query

equals

public boolean equals(Object o)

Description copied from class: Query

Override and implement query instance equivalence properly in a subclass. This is required so that QueryCache works properly. Typically a query will be equal to another only if it's an instance of the same class and its document-filtering properties are identical that other instance. Utility methods are provided for certain repetitive code.

Specified by:

equals in class Query

See Also:

Query.sameClassAs(Object), Query.classHash()

hashCode

public int hashCode()

Description copied from class: Query

Override and implement query hash code properly in a subclass. This is required so that QueryCache works properly.

Specified by:

hashCode in class Query

See Also:

Query.equals(Object)