Package org.apache.lucene.search

Class SynonymQuery

java.lang.Object

org.apache.lucene.search.Query

org.apache.lucene.search.SynonymQuery

public final class SynonymQuery
extends Query

A query that treats multiple terms as synonyms.

For scoring purposes, this query tries to score the terms as if you had indexed them as one term: it will match any of the terms but only invoke the similarity a single time, scoring the sum of all term frequencies for the document.

Constructor Summary

Constructors

Constructor	Description
SynonymQuery(Term... terms)	Creates a new SynonymQuery, matching any of the supplied terms.

Method Summary

Modifier and Type	Method	Description
Weight	createWeight(IndexSearcher searcher, boolean needsScores, float boost)	Expert: Constructs an appropriate Weight implementation for this query.
boolean	equals(Object other)	Override and implement query instance equivalence properly in a subclass.
List<Term>	getTerms()
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.

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

Constructor Detail

SynonymQuery

public SynonymQuery(Term... terms)

Creates a new SynonymQuery, matching any of the supplied terms.

The terms must all have the same field.

Method Detail

getTerms

public List<Term> getTerms()

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

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)

equals

public boolean equals(Object other)

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()

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,
                           boolean needsScores,
                           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

needsScores - True if document scores (Scorer.score()) are needed.

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

Throws:

IOException