package org.apache.lucene.search;
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
import org.apache.lucene.index.IndexReader;
import java.io.IOException;
import java.io.Serializable;
/**
* Expert: returns a comparator for sorting ScoreDocs.
*
* <p>
* Created: Apr 21, 2004 3:49:28 PM
*
* This class will be used as part of a key to a FieldCache value. You must
* implement hashCode and equals to avoid an explosion in RAM usage if you use
* instances that are not the same instance. If you are searching using the
* Remote contrib, the same instance of this class on the client will be a new
* instance on every call to the server, so hashCode/equals is very important in
* that situation.
*
* @version $Id: SortComparatorSource.java 747019 2009-02-23 13:59:50Z
* mikemccand $
* @since 1.4
* @deprecated Please use {@link FieldComparatorSource} instead.
*/
public interface SortComparatorSource
extends Serializable {
/**
* Creates a comparator for the field in the given index.
* @param reader Index to create comparator for.
* @param fieldname Name of the field to create comparator for.
* @return Comparator of ScoreDoc objects.
* @throws IOException If an error occurs reading the index.
*/
ScoreDocComparator newComparator (IndexReader reader, String fieldname)
throws IOException;
}