/*
* 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.
*/
package org.apache.jackrabbit.core.query.lucene;
import java.io.IOException;
/**
* <code>HierarchyResolver</code> extends an {@link org.apache.lucene.index.IndexReader}
* with the ability to resolve a JCR hierarchy.
*/
public interface HierarchyResolver {
/**
* Returns the document number of the parent of <code>n</code> or an empty
* array if <code>n</code> does not have a parent (<code>n</code> is the
* root node).
*
* @param n the document number.
* @param docNumbers an array for reuse. An implementation should use the
* passed array as a container for the return value,
* unless the length of the returned array is different
* from <code>docNumbers</code>. In which case an
* implementation will create a new array with an
* appropriate size.
* @return the document number of <code>n</code>'s parent.
* @throws java.io.IOException if an error occurs while reading from the
* index.
*/
int[] getParents(int n, int[] docNumbers) throws IOException;
}