/*
* Created on 25-Jan-2006
*/
package org.apache.lucene.xmlparser.builders;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.search.similar.MoreLikeThisQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.xmlparser.DOMUtils;
import org.apache.lucene.xmlparser.ParserException;
import org.apache.lucene.xmlparser.QueryBuilder;
import org.w3c.dom.Element;
/**
* @author maharwood
*/
public class LikeThisQueryBuilder implements QueryBuilder {
private Analyzer analyzer;
String defaultFieldNames [];
int defaultMaxQueryTerms=20;
int defaultMinTermFrequency=1;
float defaultPercentTermsToMatch=30; //default is a 3rd of selected terms must match
public LikeThisQueryBuilder(Analyzer analyzer,String [] defaultFieldNames)
{
this.analyzer=analyzer;
this.defaultFieldNames=defaultFieldNames;
}
/* (non-Javadoc)
* @see org.apache.lucene.xmlparser.QueryObjectBuilder#process(org.w3c.dom.Element)
*/
public Query getQuery(Element e) throws ParserException {
String fieldsList=e.getAttribute("fieldNames"); //a comma-delimited list of fields
String fields[]=defaultFieldNames;
if((fieldsList!=null)&&(fieldsList.trim().length()>0))
{
fields=fieldsList.trim().split(",");
//trim the fieldnames
for (int i = 0; i < fields.length; i++) {
fields[i]=fields[i].trim();
}
}
MoreLikeThisQuery mlt=new MoreLikeThisQuery(DOMUtils.getText(e),fields,analyzer);
mlt.setMaxQueryTerms(DOMUtils.getAttribute(e,"maxQueryTerms",defaultMaxQueryTerms));
mlt.setMinTermFrequency(DOMUtils.getAttribute(e,"minTermFrequency",defaultMinTermFrequency));
mlt.setPercentTermsToMatch(DOMUtils.getAttribute(e,"percentTermsToMatch",defaultPercentTermsToMatch)/100);
mlt.setBoost(DOMUtils.getAttribute(e,"boost",1.0f));
return mlt;
}
}