org.apache.lucene.queries.function

Class FunctionQuery

java.lang.Object

org.apache.lucene.search.Query

org.apache.lucene.queries.function.FunctionQuery

All Implemented Interfaces:

Cloneable

public class FunctionQuery
extends Query

Returns a score for each document based on a ValueSource, often some function of the value of a field.

See Also:

ValueSourceScorer

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	FunctionQuery.AllScorer
protected class	FunctionQuery.FunctionWeight

Constructor Summary

Constructors

Constructor and Description
FunctionQuery(ValueSource func)

Method Summary

Methods

Modifier and Type	Method and Description
Weight	createWeight(IndexSearcher searcher, boolean needsScores) Expert: Constructs an appropriate Weight implementation for this query.
boolean	equals(Object o) Returns true if o is equal to this.
ValueSource	getValueSource()
int	hashCode()
String	toString(String field) Prints a user-readable version of this query.

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

clone, getBoost, rewrite, setBoost, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

FunctionQuery

public FunctionQuery(ValueSource func)

Parameters:

func - defines the function to be used for scoring

Method Detail

getValueSource

public ValueSource getValueSource()

Returns:

The associated ValueSource

createWeight

public Weight createWeight(IndexSearcher searcher,
                  boolean needsScores)
                    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

needsScores - True if document scores (Scorer.score()) or match frequencies (Scorer.freq()) are needed.

Throws:

IOException

toString

public String toString(String field)

Prints a user-readable version of this query.

Specified by:

toString in class Query

equals

public boolean equals(Object o)

Returns true if o is equal to this.

Overrides:

equals in class Query

hashCode

public int hashCode()

Overrides:

hashCode in class Query