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* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.index.search.child;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.SortedDocValues;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.BitsFilteredDocIdSet;
import org.apache.lucene.search.CollectionTerminatedException;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.Explanation;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.search.Weight;
import org.apache.lucene.search.XFilteredDocIdSetIterator;
import org.apache.lucene.search.join.BitDocIdSetFilter;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.LongBitSet;
import org.elasticsearch.common.lucene.docset.DocIdSets;
import org.elasticsearch.common.lucene.search.NoopCollector;
import org.elasticsearch.common.lucene.search.Queries;
import org.elasticsearch.index.fielddata.AtomicParentChildFieldData;
import org.elasticsearch.index.fielddata.IndexParentChildFieldData;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
import java.util.List;
import java.util.Set;
/**
*
*/
public class ChildrenConstantScoreQuery extends Query {
private final IndexParentChildFieldData parentChildIndexFieldData;
private Query originalChildQuery;
private final String parentType;
private final String childType;
private final BitDocIdSetFilter parentFilter;
private final int shortCircuitParentDocSet;
private final BitDocIdSetFilter nonNestedDocsFilter;
private Query rewrittenChildQuery;
private IndexReader rewriteIndexReader;
public ChildrenConstantScoreQuery(IndexParentChildFieldData parentChildIndexFieldData, Query childQuery, String parentType, String childType, BitDocIdSetFilter parentFilter, int shortCircuitParentDocSet, BitDocIdSetFilter nonNestedDocsFilter) {
this.parentChildIndexFieldData = parentChildIndexFieldData;
this.parentFilter = parentFilter;
this.parentType = parentType;
this.childType = childType;
this.originalChildQuery = childQuery;
this.shortCircuitParentDocSet = shortCircuitParentDocSet;
this.nonNestedDocsFilter = nonNestedDocsFilter;
}
@Override
// See TopChildrenQuery#rewrite
public Query rewrite(IndexReader reader) throws IOException {
if (rewrittenChildQuery == null) {
rewrittenChildQuery = originalChildQuery.rewrite(reader);
rewriteIndexReader = reader;
}
return this;
}
@Override
public void extractTerms(Set<Term> terms) {
rewrittenChildQuery.extractTerms(terms);
}
@Override
public Query clone() {
ChildrenConstantScoreQuery q = (ChildrenConstantScoreQuery) super.clone();
q.originalChildQuery = originalChildQuery.clone();
if (q.rewrittenChildQuery != null) {
q.rewrittenChildQuery = rewrittenChildQuery.clone();
}
return q;
}
@Override
public Weight createWeight(IndexSearcher searcher) throws IOException {
SearchContext sc = SearchContext.current();
IndexParentChildFieldData globalIfd = parentChildIndexFieldData.loadGlobal(searcher.getIndexReader());
assert rewrittenChildQuery != null;
assert rewriteIndexReader == searcher.getIndexReader() : "not equal, rewriteIndexReader=" + rewriteIndexReader + " searcher.getIndexReader()=" + searcher.getIndexReader();
final long valueCount;
List<LeafReaderContext> leaves = searcher.getIndexReader().leaves();
if (globalIfd == null || leaves.isEmpty()) {
return Queries.newMatchNoDocsQuery().createWeight(searcher);
} else {
AtomicParentChildFieldData afd = globalIfd.load(leaves.get(0));
SortedDocValues globalValues = afd.getOrdinalsValues(parentType);
valueCount = globalValues.getValueCount();
}
if (valueCount == 0) {
return Queries.newMatchNoDocsQuery().createWeight(searcher);
}
Query childQuery = rewrittenChildQuery;
IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());
indexSearcher.setSimilarity(searcher.getSimilarity());
ParentOrdCollector collector = new ParentOrdCollector(globalIfd, valueCount, parentType);
indexSearcher.search(childQuery, collector);
final long remaining = collector.foundParents();
if (remaining == 0) {
return Queries.newMatchNoDocsQuery().createWeight(searcher);
}
Filter shortCircuitFilter = null;
if (remaining <= shortCircuitParentDocSet) {
shortCircuitFilter = ParentIdsFilter.createShortCircuitFilter(
nonNestedDocsFilter, sc, parentType, collector.values, collector.parentOrds, remaining
);
}
return new ParentWeight(parentFilter, globalIfd, shortCircuitFilter, collector, remaining);
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null || obj.getClass() != this.getClass()) {
return false;
}
ChildrenConstantScoreQuery that = (ChildrenConstantScoreQuery) obj;
if (!originalChildQuery.equals(that.originalChildQuery)) {
return false;
}
if (!childType.equals(that.childType)) {
return false;
}
if (shortCircuitParentDocSet != that.shortCircuitParentDocSet) {
return false;
}
if (getBoost() != that.getBoost()) {
return false;
}
return true;
}
@Override
public int hashCode() {
int result = originalChildQuery.hashCode();
result = 31 * result + childType.hashCode();
result = 31 * result + shortCircuitParentDocSet;
result = 31 * result + Float.floatToIntBits(getBoost());
return result;
}
@Override
public String toString(String field) {
return "child_filter[" + childType + "/" + parentType + "](" + originalChildQuery + ')';
}
private final class ParentWeight extends Weight {
private final Filter parentFilter;
private final Filter shortCircuitFilter;
private final ParentOrdCollector collector;
private final IndexParentChildFieldData globalIfd;
private long remaining;
private float queryNorm;
private float queryWeight;
public ParentWeight(Filter parentFilter, IndexParentChildFieldData globalIfd, Filter shortCircuitFilter, ParentOrdCollector collector, long remaining) {
this.parentFilter = parentFilter;
this.globalIfd = globalIfd;
this.shortCircuitFilter = shortCircuitFilter;
this.collector = collector;
this.remaining = remaining;
}
@Override
public Explanation explain(LeafReaderContext context, int doc) throws IOException {
return new Explanation(getBoost(), "not implemented yet...");
}
@Override
public Query getQuery() {
return ChildrenConstantScoreQuery.this;
}
@Override
public float getValueForNormalization() throws IOException {
queryWeight = getBoost();
return queryWeight * queryWeight;
}
@Override
public void normalize(float norm, float topLevelBoost) {
this.queryNorm = norm * topLevelBoost;
queryWeight *= this.queryNorm;
}
@Override
public Scorer scorer(LeafReaderContext context, Bits acceptDocs) throws IOException {
if (remaining == 0) {
return null;
}
if (shortCircuitFilter != null) {
DocIdSet docIdSet = shortCircuitFilter.getDocIdSet(context, acceptDocs);
if (!DocIdSets.isEmpty(docIdSet)) {
DocIdSetIterator iterator = docIdSet.iterator();
if (iterator != null) {
return ConstantScorer.create(iterator, this, queryWeight);
}
}
return null;
}
DocIdSet parentDocIdSet = this.parentFilter.getDocIdSet(context, acceptDocs);
if (!DocIdSets.isEmpty(parentDocIdSet)) {
// We can't be sure of the fact that liveDocs have been applied, so we apply it here. The "remaining"
// count down (short circuit) logic will then work as expected.
parentDocIdSet = BitsFilteredDocIdSet.wrap(parentDocIdSet, context.reader().getLiveDocs());
DocIdSetIterator innerIterator = parentDocIdSet.iterator();
if (innerIterator != null) {
LongBitSet parentOrds = collector.parentOrds;
SortedDocValues globalValues = globalIfd.load(context).getOrdinalsValues(parentType);
if (globalValues != null) {
DocIdSetIterator parentIdIterator = new ParentOrdIterator(innerIterator, parentOrds, globalValues, this);
return ConstantScorer.create(parentIdIterator, this, queryWeight);
}
}
}
return null;
}
}
private final static class ParentOrdCollector extends NoopCollector {
private final LongBitSet parentOrds;
private final IndexParentChildFieldData indexFieldData;
private final String parentType;
private SortedDocValues values;
private ParentOrdCollector(IndexParentChildFieldData indexFieldData, long maxOrd, String parentType) {
// TODO: look into reusing LongBitSet#bits array
this.parentOrds = new LongBitSet(maxOrd + 1);
this.indexFieldData = indexFieldData;
this.parentType = parentType;
}
@Override
public void collect(int doc) throws IOException {
if (values != null) {
int globalOrdinal = values.getOrd(doc);
// TODO: oversize the long bitset and remove the branch
if (globalOrdinal >= 0) {
parentOrds.set(globalOrdinal);
}
}
}
@Override
protected void doSetNextReader(LeafReaderContext context) throws IOException {
values = indexFieldData.load(context).getOrdinalsValues(parentType);
}
long foundParents() {
return parentOrds.cardinality();
}
}
private final static class ParentOrdIterator extends XFilteredDocIdSetIterator {
private final LongBitSet parentOrds;
private final SortedDocValues ordinals;
private final ParentWeight parentWeight;
private ParentOrdIterator(DocIdSetIterator innerIterator, LongBitSet parentOrds, SortedDocValues ordinals, ParentWeight parentWeight) {
super(innerIterator);
this.parentOrds = parentOrds;
this.ordinals = ordinals;
this.parentWeight = parentWeight;
}
@Override
protected boolean match(int doc) {
if (parentWeight.remaining == 0) {
throw new CollectionTerminatedException();
}
long parentOrd = ordinals.getOrd(doc);
if (parentOrd >= 0) {
boolean match = parentOrds.get(parentOrd);
if (match) {
parentWeight.remaining--;
}
return match;
}
return false;
}
}
}