/*
* JBoss, Home of Professional Open Source
* Copyright 2011 Red Hat Inc. and/or its affiliates and other contributors
* as indicated by the @authors tag. All rights reserved.
* See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License, v. 2.1.
* This program is distributed in the hope that it will be useful, but WITHOUT A
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
* You should have received a copy of the GNU Lesser General Public License,
* v.2.1 along with this distribution; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
package org.hibernate.search.test.filter;
import java.io.IOException;
import java.io.Serializable;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.Filter;
/**
* Apparently it's legal for Lucene filters to return null
* on {@link DocIdSet#iterator()} : make sure we can deal with it as well.
*
* @author Sanne Grinovero <sanne@hibernate.org> (C) 2011 Red Hat Inc.
*/
public class NullReturningEmptyFilter extends Filter implements Serializable {
public static final DocIdSet EMPTY_DOCIDSET = new DocIdSet() {
@Override
public DocIdSetIterator iterator() {
return null;
}
@Override
public boolean isCacheable() {
return true;
}
};
@Override
public DocIdSet getDocIdSet(IndexReader reader) throws IOException {
return EMPTY_DOCIDSET;
}
}