org.cdlib.xtf.textEngine
Class StdTermRewriter
Object
QueryRewriter
XtfQueryRewriter
StdTermRewriter
public class StdTermRewriter
- extends XtfQueryRewriter
Rewrites a Lucene query to perform standard tokenization actions on
each term, such as converting them to lowercase, removing apostrophes,
etc.
- Author:
- Martin Haye
Constructor Summary |
StdTermRewriter(Set tokFields)
Construct a term rewriter that will operate on the given tokenized
fields. |
Method Summary |
private String |
mapTerm(Term t)
Map the given term and return the mapped result. |
protected Query |
rewrite(SpanTermQuery q)
Rewrite a span term query. |
protected Query |
rewrite(SpanWildcardQuery q)
Rewrite a wildcard term query. |
protected Query |
rewrite(TermQuery q)
Rewrite a term query. |
Methods inherited from class QueryRewriter |
combineBoost, copyBoost, copyBoost, forceRewrite, 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 |
tokenizedFields
private Set tokenizedFields
filter
private StdTermFilter filter
StdTermRewriter
public StdTermRewriter(Set tokFields)
- Construct a term rewriter that will operate on the given tokenized
fields.
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.
- 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(SpanWildcardQuery q)
- Rewrite a wildcard term query.
- Overrides:
rewrite
in class QueryRewriter
- Parameters:
q
- The query to rewrite
- Returns:
- Rewritten version, or 'q' unchanged if no changed needed.
mapTerm
private String mapTerm(Term t)
- Map the given term and return the mapped result.
- Parameters:
t
- term to map
- Returns:
- different term, or null if not different. Also null if the
field isn't tokenized.