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* 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
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package org.elasticsearch.search.aggregations.bucket.significant;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.LeafReaderContext;
import org.elasticsearch.common.lease.Releasables;
import org.elasticsearch.search.aggregations.Aggregator;
import org.elasticsearch.search.aggregations.AggregatorFactories;
import org.elasticsearch.search.aggregations.LeafBucketCollector;
import org.elasticsearch.search.aggregations.LeafBucketCollectorBase;
import org.elasticsearch.search.aggregations.bucket.terms.LongTermsAggregator;
import org.elasticsearch.search.aggregations.bucket.terms.support.IncludeExclude;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
import org.elasticsearch.search.aggregations.support.AggregationContext;
import org.elasticsearch.search.aggregations.support.ValuesSource;
import org.elasticsearch.search.aggregations.support.format.ValueFormat;
import org.elasticsearch.search.internal.ContextIndexSearcher;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Map;
/**
*
*/
public class SignificantLongTermsAggregator extends LongTermsAggregator {
public SignificantLongTermsAggregator(String name, AggregatorFactories factories, ValuesSource.Numeric valuesSource,
ValueFormat format, BucketCountThresholds bucketCountThresholds, AggregationContext aggregationContext, Aggregator parent,
SignificantTermsAggregatorFactory termsAggFactory, IncludeExclude.LongFilter includeExclude,
List<PipelineAggregator> pipelineAggregators, Map<String, Object> metaData) throws IOException {
super(name, factories, valuesSource, format, null, bucketCountThresholds, aggregationContext, parent,
SubAggCollectionMode.DEPTH_FIRST, false, includeExclude, pipelineAggregators, metaData);
this.termsAggFactory = termsAggFactory;
}
protected long numCollectedDocs;
private final SignificantTermsAggregatorFactory termsAggFactory;
@Override
public LeafBucketCollector getLeafCollector(LeafReaderContext ctx,
final LeafBucketCollector sub) throws IOException {
return new LeafBucketCollectorBase(super.getLeafCollector(ctx, sub), null) {
@Override
public void collect(int doc, long bucket) throws IOException {
super.collect(doc, bucket);
numCollectedDocs++;
}
};
}
@Override
public SignificantLongTerms buildAggregation(long owningBucketOrdinal) throws IOException {
assert owningBucketOrdinal == 0;
final int size = (int) Math.min(bucketOrds.size(), bucketCountThresholds.getShardSize());
long supersetSize = termsAggFactory.prepareBackground(context);
long subsetSize = numCollectedDocs;
BucketSignificancePriorityQueue ordered = new BucketSignificancePriorityQueue(size);
SignificantLongTerms.Bucket spare = null;
for (long i = 0; i < bucketOrds.size(); i++) {
final int docCount = bucketDocCount(i);
if (docCount < bucketCountThresholds.getShardMinDocCount()) {
continue;
}
if (spare == null) {
spare = new SignificantLongTerms.Bucket(0, 0, 0, 0, 0, null, formatter);
}
spare.term = bucketOrds.get(i);
spare.subsetDf = docCount;
spare.subsetSize = subsetSize;
spare.supersetDf = termsAggFactory.getBackgroundFrequency(spare.term);
spare.supersetSize = supersetSize;
// During shard-local down-selection we use subset/superset stats that are for this shard only
// Back at the central reducer these properties will be updated with global stats
spare.updateScore(termsAggFactory.getSignificanceHeuristic());
spare.bucketOrd = i;
spare = (SignificantLongTerms.Bucket) ordered.insertWithOverflow(spare);
}
final InternalSignificantTerms.Bucket[] list = new InternalSignificantTerms.Bucket[ordered.size()];
for (int i = ordered.size() - 1; i >= 0; i--) {
final SignificantLongTerms.Bucket bucket = (SignificantLongTerms.Bucket) ordered.pop();
bucket.aggregations = bucketAggregations(bucket.bucketOrd);
list[i] = bucket;
}
return new SignificantLongTerms(subsetSize, supersetSize, name, formatter, bucketCountThresholds.getRequiredSize(),
bucketCountThresholds.getMinDocCount(), termsAggFactory.getSignificanceHeuristic(), Arrays.asList(list), pipelineAggregators(),
metaData());
}
@Override
public SignificantLongTerms buildEmptyAggregation() {
// We need to account for the significance of a miss in our global stats - provide corpus size as context
ContextIndexSearcher searcher = context.searchContext().searcher();
IndexReader topReader = searcher.getIndexReader();
int supersetSize = topReader.numDocs();
return new SignificantLongTerms(0, supersetSize, name, formatter, bucketCountThresholds.getRequiredSize(),
bucketCountThresholds.getMinDocCount(), termsAggFactory.getSignificanceHeuristic(),
Collections.<InternalSignificantTerms.Bucket> emptyList(), pipelineAggregators(), metaData());
}
@Override
public void doClose() {
Releasables.close(bucketOrds, termsAggFactory);
}
}