org.apache.lucene.search.DeletionAwareConstantScoreQuery Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of elasticsearch Show documentation
Show all versions of elasticsearch Show documentation
Elasticsearch subproject :server
/*
* Licensed to Elastic Search and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Elastic Search 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.lucene.search;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import java.io.IOException;
import java.util.Set;
/**
* @author kimchy (shay.banon)
*/
// LUCENE MONITOR: Against ConstantScoreQuery, basically added logic in the doc iterator to take deletions into account
// So it can basically be cached safely even with a reader that changes deletions but remain with teh same cache key
// See more: https://issues.apache.org/jira/browse/LUCENE-2468
public class DeletionAwareConstantScoreQuery extends Query {
protected final Filter filter;
public DeletionAwareConstantScoreQuery(Filter filter) {
this.filter = filter;
}
/**
* Returns the encapsulated filter
*/
public Filter getFilter() {
return filter;
}
@Override
public Query rewrite(IndexReader reader) throws IOException {
return this;
}
@Override
public void extractTerms(Set terms) {
// OK to not add any terms when used for MultiSearcher,
// but may not be OK for highlighting
}
protected class ConstantWeight extends Weight {
private Similarity similarity;
private float queryNorm;
private float queryWeight;
public ConstantWeight(Searcher searcher) {
this.similarity = getSimilarity(searcher);
}
@Override
public Query getQuery() {
return DeletionAwareConstantScoreQuery.this;
}
@Override
public float getValue() {
return queryWeight;
}
@Override
public float sumOfSquaredWeights() throws IOException {
queryWeight = getBoost();
return queryWeight * queryWeight;
}
@Override
public void normalize(float norm) {
this.queryNorm = norm;
queryWeight *= this.queryNorm;
}
@Override
public Scorer scorer(IndexReader reader, boolean scoreDocsInOrder, boolean topScorer) throws IOException {
return new ConstantScorer(similarity, reader, this);
}
@Override
public Explanation explain(IndexReader reader, int doc) throws IOException {
ConstantScorer cs = new ConstantScorer(similarity, reader, this);
boolean exists = cs._innerIter.advance(doc) == doc;
ComplexExplanation result = new ComplexExplanation();
if (exists) {
result.setDescription("ConstantScoreQuery(" + filter
+ "), product of:");
result.setValue(queryWeight);
result.setMatch(Boolean.TRUE);
result.addDetail(new Explanation(getBoost(), "boost"));
result.addDetail(new Explanation(queryNorm, "queryNorm"));
} else {
result.setDescription("ConstantScoreQuery(" + filter
+ ") doesn't match id " + doc);
result.setValue(0);
result.setMatch(Boolean.FALSE);
}
return result;
}
}
protected class ConstantScorer extends Scorer {
final IndexReader reader;
final DocIdSetIterator _innerIter;
final float theScore;
private int doc = -1;
public ConstantScorer(Similarity similarity, IndexReader reader, Weight w) throws IOException {
super(similarity);
this.reader = reader;
theScore = w.getValue();
DocIdSet docIdSet = filter.getDocIdSet(reader);
if (docIdSet == null) {
_innerIter = DocIdSet.EMPTY_DOCIDSET.iterator();
} else {
DocIdSetIterator iter = docIdSet.iterator();
if (iter == null) {
_innerIter = DocIdSet.EMPTY_DOCIDSET.iterator();
} else {
_innerIter = iter;
}
}
}
@Override
public int nextDoc() throws IOException {
while ((doc = _innerIter.nextDoc()) != NO_MORE_DOCS) {
if (!reader.isDeleted(doc)) {
return doc;
}
}
return doc;
}
@Override
public int docID() {
return doc;
}
@Override
public float score() throws IOException {
return theScore;
}
@Override
public int advance(int target) throws IOException {
doc = _innerIter.advance(target);
if (doc != NO_MORE_DOCS) {
if (!reader.isDeleted(doc)) {
return doc;
} else {
while ((doc = _innerIter.nextDoc()) != NO_MORE_DOCS) {
if (!reader.isDeleted(doc)) {
return doc;
}
}
return doc;
}
}
return doc;
}
}
@Override
public Weight createWeight(Searcher searcher) {
return new DeletionAwareConstantScoreQuery.ConstantWeight(searcher);
}
/**
* Prints a user-readable version of this query.
*/
@Override
public String toString(String field) {
return "ConstantScore(" + filter.toString()
+ (getBoost() == 1.0 ? ")" : "^" + getBoost());
}
/**
* Returns true if o is equal to this.
*/
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof DeletionAwareConstantScoreQuery)) return false;
DeletionAwareConstantScoreQuery other = (DeletionAwareConstantScoreQuery) o;
return this.getBoost() == other.getBoost() && filter.equals(other.filter);
}
/**
* Returns a hash code value for this object.
*/
@Override
public int hashCode() {
// Simple add is OK since no existing filter hashcode has a float component.
return filter.hashCode() + Float.floatToIntBits(getBoost());
}
}