/**
* Copyright 2014 National University of Ireland, Galway.
*
* This file is part of the SIREn project. Project and contact information:
*
* https://github.com/rdelbru/SIREn
*
* 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.sindice.siren.search.node;
import java.io.IOException;
import org.apache.lucene.util.IntsRef;
import org.sindice.siren.index.DocsAndNodesIterator;
/**
* A {@link NodeScorer} that filters node path and output the ancestor node path.
*
* <p>
*
* The level of the ancestor must be specified. It is used to modify the
* {@link IntsRef#length} of the node label returned by the inner scorer.
*/
class AncestorFilterScorer extends NodeScorer {
private final NodeScorer scorer;
private final int ancestorLevel;
public AncestorFilterScorer(final NodeScorer scorer, final int ancestorLevel) {
super(scorer.getWeight());
this.scorer = scorer;
this.ancestorLevel = ancestorLevel;
}
protected NodeScorer getScorer() {
return scorer;
}
@Override
public float freqInNode() throws IOException {
return scorer.freqInNode();
}
@Override
public float scoreInNode()
throws IOException {
return scorer.scoreInNode();
}
@Override
public String toString() {
return "AncestorFilterScorer(" + weight + "," + this.doc() + "," +
this.node() + ")";
}
@Override
public boolean nextCandidateDocument() throws IOException {
return scorer.nextCandidateDocument();
}
@Override
public boolean nextNode() throws IOException {
return scorer.nextNode();
}
@Override
public boolean skipToCandidate(final int target) throws IOException {
return scorer.skipToCandidate(target);
}
@Override
public int doc() {
return scorer.doc();
}
@Override
public IntsRef node() {
final IntsRef node = scorer.node();
// resize node array only if node is not a sentinel value
if (node.length > ancestorLevel &&
node.ints[node.offset] != -1 &&
node != DocsAndNodesIterator.NO_MORE_NOD) {
node.length = ancestorLevel;
}
return node;
}
}