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* 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
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package org.elasticsearch.search.aggregations.bucket.nested;
import org.apache.lucene.index.IndexReaderContext;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.ReaderUtil;
import org.apache.lucene.search.DocIdSetIterator;
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.join.BitSetProducer;
import org.apache.lucene.util.BitSet;
import org.elasticsearch.common.ParseField;
import org.elasticsearch.common.lucene.search.Queries;
import org.elasticsearch.index.mapper.ObjectMapper;
import org.elasticsearch.search.aggregations.Aggregator;
import org.elasticsearch.search.aggregations.AggregatorFactories;
import org.elasticsearch.search.aggregations.InternalAggregation;
import org.elasticsearch.search.aggregations.LeafBucketCollector;
import org.elasticsearch.search.aggregations.LeafBucketCollectorBase;
import org.elasticsearch.search.aggregations.bucket.SingleBucketAggregator;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
import java.util.List;
import java.util.Map;
class NestedAggregator extends SingleBucketAggregator {
static final ParseField PATH_FIELD = new ParseField("path");
private final BitSetProducer parentFilter;
private final Query childFilter;
NestedAggregator(String name, AggregatorFactories factories, ObjectMapper parentObjectMapper, ObjectMapper childObjectMapper,
SearchContext context, Aggregator parentAggregator,
List<PipelineAggregator> pipelineAggregators, Map<String, Object> metaData) throws IOException {
super(name, factories, context, parentAggregator, pipelineAggregators, metaData);
Query parentFilter = parentObjectMapper != null ? parentObjectMapper.nestedTypeFilter() : Queries.newNonNestedFilter();
this.parentFilter = context.bitsetFilterCache().getBitSetProducer(parentFilter);
this.childFilter = childObjectMapper.nestedTypeFilter();
}
@Override
public LeafBucketCollector getLeafCollector(final LeafReaderContext ctx, final LeafBucketCollector sub) throws IOException {
IndexReaderContext topLevelContext = ReaderUtil.getTopLevelContext(ctx);
IndexSearcher searcher = new IndexSearcher(topLevelContext);
searcher.setQueryCache(null);
Weight weight = searcher.createNormalizedWeight(childFilter, false);
Scorer childDocsScorer = weight.scorer(ctx);
final BitSet parentDocs = parentFilter.getBitSet(ctx);
final DocIdSetIterator childDocs = childDocsScorer != null ? childDocsScorer.iterator() : null;
return new LeafBucketCollectorBase(sub, null) {
@Override
public void collect(int parentDoc, long bucket) throws IOException {
// if parentDoc is 0 then this means that this parent doesn't have child docs (b/c these appear always before the parent
// doc), so we can skip:
if (parentDoc == 0 || parentDocs == null || childDocs == null) {
return;
}
final int prevParentDoc = parentDocs.prevSetBit(parentDoc - 1);
int childDocId = childDocs.docID();
if (childDocId <= prevParentDoc) {
childDocId = childDocs.advance(prevParentDoc + 1);
}
for (; childDocId < parentDoc; childDocId = childDocs.nextDoc()) {
collectBucket(sub, childDocId, bucket);
}
}
};
}
@Override
public InternalAggregation buildAggregation(long owningBucketOrdinal) throws IOException {
return new InternalNested(name, bucketDocCount(owningBucketOrdinal), bucketAggregations(owningBucketOrdinal),
pipelineAggregators(), metaData());
}
@Override
public InternalAggregation buildEmptyAggregation() {
return new InternalNested(name, 0, buildEmptySubAggregations(), pipelineAggregators(), metaData());
}
}