// $Id: QueryHits.java 15563 2008-11-13 16:02:44Z hardy.ferentschik $
/*
* JBoss, Home of Professional Open Source
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.hibernate.search.query;
import java.io.IOException;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.FieldSelector;
import org.apache.lucene.search.Explanation;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.Searcher;
import org.apache.lucene.search.Sort;
import org.apache.lucene.search.TopDocs;
import org.hibernate.search.SearchException;
/**
* A helper class which gives access to the current query and its hits. This class will dynamically
* reload the underlying <code>TopDocs</code> if required.
*
* @author Hardy Ferentschik
*/
public class QueryHits {
private static final int DEFAULT_TOP_DOC_RETRIEVAL_SIZE = 100;
public final org.apache.lucene.search.Query preparedQuery;
public final Searcher searcher;
public final Filter filter;
public final Sort sort;
public final int totalHits;
public TopDocs topDocs;
public QueryHits(Searcher searcher, org.apache.lucene.search.Query preparedQuery, Filter filter, Sort sort)
throws IOException {
this.preparedQuery = preparedQuery;
this.searcher = searcher;
this.filter = filter;
this.sort = sort;
updateTopDocs( DEFAULT_TOP_DOC_RETRIEVAL_SIZE );
totalHits = topDocs.totalHits;
}
public Document doc(int index) throws IOException {
return searcher.doc( docId( index ) );
}
public Document doc(int index, FieldSelector selector) throws IOException {
return searcher.doc( docId( index ), selector );
}
public ScoreDoc scoreDoc(int index) throws IOException {
if ( index >= totalHits ) {
throw new SearchException("Not a valid ScoreDoc index: " + index);
}
// TODO - Is there a better way to get more TopDocs? Get more or less?
if ( index >= topDocs.scoreDocs.length ) {
updateTopDocs( 2 * index );
}
return topDocs.scoreDocs[index];
}
public int docId(int index) throws IOException {
return scoreDoc( index ).doc;
}
public float score(int index) throws IOException {
return scoreDoc( index ).score;
}
public Explanation explain(int index) throws IOException {
return searcher.explain( preparedQuery, docId( index ) );
}
private void updateTopDocs(int n) throws IOException {
if ( sort == null ) {
topDocs = searcher.search( preparedQuery, filter, n );
}
else {
topDocs = searcher.search( preparedQuery, filter, n, sort );
}
}
}