/*
* 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.exoplatform.services.jcr.impl.core.query.lucene;
import org.exoplatform.services.jcr.impl.core.SessionImpl;
import java.io.IOException;
import javax.jcr.Node;
import javax.jcr.RepositoryException;
/**
* <code>ChildNodesQueryHits</code> implements query hits that returns the child
* nodes of another given query hits.
*/
public class ChildNodesQueryHits extends AbstractQueryHits {
/**
* The parent query hits.
*/
private final QueryHits parents;
/**
* This session that executes the query.
*/
private final SessionImpl session;
/**
* The current child hits.
*/
private QueryHits childHits;
private IndexingConfiguration indexConfig;
/**
* Creates a new <code>ChildNodesQueryHits</code> that returns the child
* nodes of all query hits from the given <code>parents</code>.
*
* @param parents the parent query hits.
* @param session the session that executes the query.
* @throws IOException if an error occurs while reading from
* <code>parents</code>
*/
public ChildNodesQueryHits(QueryHits parents, SessionImpl session, IndexingConfiguration indexConfig)
throws IOException {
this.parents = parents;
this.session = session;
this.indexConfig = indexConfig;
fetchNextChildHits();
}
/**
* {@inheritDoc}
*/
public void close() throws IOException {
if (childHits != null) {
childHits.close();
}
parents.close();
}
/**
* {@inheritDoc}
*/
public ScoreNode nextScoreNode() throws IOException {
while (childHits != null) {
ScoreNode sn = childHits.nextScoreNode();
if (sn != null) {
return sn;
} else {
fetchNextChildHits();
}
}
// if we get here there are no more score nodes
return null;
}
/**
* Fetches the next {@link #childHits}
* @throws IOException
*/
private void fetchNextChildHits() throws IOException {
if (childHits != null) {
childHits.close();
}
ScoreNode nextParent = parents.nextScoreNode();
if (nextParent != null) {
try {
Node parent = (Node)session.getTransientNodesManager().getItemByIdentifier(nextParent.getNodeId(),true);
childHits = new NodeTraversingQueryHits(parent, false, 1, indexConfig);
} catch (RepositoryException e) {
throw Util.createIOException(e);
}
} else {
childHits = null;
}
}
}