org.cdlib.xtf.textEngine

Class PluralFoldingRewriter

Object

QueryRewriter

XtfQueryRewriter

PluralFoldingRewriter

public class PluralFoldingRewriter
extends XtfQueryRewriter

Rewrites a Lucene query to replace all plural words with their singular equivalents.

Author:

Martin Haye

Nested Class Summary

Nested classes/interfaces inherited from class QueryRewriter

QueryRewriter.SpanClauseJoiner

Field Summary

Fields

Modifier and Type	Field and Description
private WordMap	pluralMap
private Set	tokenizedFields

Constructor Summary

Constructors

Constructor and Description
PluralFoldingRewriter(WordMap pluralMap, Set tokFields) Construct a new rewriter to use the given map

Method Summary

Modifier and Type	Method and Description
protected Query	rewrite(SpanTermQuery q) Rewrite a span term query.
protected Query	rewrite(TermQuery q) Rewrite a term query.

Methods inherited from class XtfQueryRewriter

rewrite, rewrite, rewrite, rewrite, rewriteQuery

Methods inherited from class QueryRewriter

combineBoost, copyBoost, copyBoost, forceRewrite, rewrite, rewrite, rewrite, rewrite, rewrite, rewrite, rewrite, rewrite, rewrite, rewrite, rewriteClauses

Methods inherited from class Object

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

Field Detail

pluralMap

private WordMap pluralMap

tokenizedFields

private Set tokenizedFields

Constructor Detail

PluralFoldingRewriter

public PluralFoldingRewriter(WordMap pluralMap,
                             Set tokFields)

Construct a new rewriter to use the given map

Method Detail

rewrite

protected Query rewrite(TermQuery q)

Rewrite a term query. This is only called for artificial queries introduced by XTF system itself, and therefore we don't map here.

Overrides:

rewrite in class QueryRewriter

Parameters:

q - The query to rewrite

Returns:

Rewritten version, or 'q' unchanged if no changed needed.

rewrite

protected Query rewrite(SpanTermQuery q)

Rewrite a span term query. Maps plural words to singular, but only for tokenized fields.

Overrides:

rewrite in class QueryRewriter

Parameters:

q - The query to rewrite

Returns:

Rewritten version, or 'q' unchanged if no changed needed.