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* 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.
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package org.elasticsearch.search.aggregations.bucket.histogram;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.util.CollectionUtil;
import org.elasticsearch.common.inject.internal.Nullable;
import org.elasticsearch.common.lease.Releasables;
import org.elasticsearch.common.util.LongHash;
import org.elasticsearch.index.fielddata.SortedNumericDoubleValues;
import org.elasticsearch.search.DocValueFormat;
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.BucketsAggregator;
import org.elasticsearch.search.aggregations.bucket.histogram.InternalHistogram.EmptyBucketInfo;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
import org.elasticsearch.search.aggregations.BucketOrder;
import org.elasticsearch.search.aggregations.InternalOrder;
import org.elasticsearch.search.aggregations.support.ValuesSource;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
/**
* An aggregator for numeric values. For a given {@code interval},
* {@code offset} and {@code value}, it returns the highest number that can be
* written as {@code interval * x + offset} and yet is less than or equal to
* {@code value}.
*/
class HistogramAggregator extends BucketsAggregator {
private final ValuesSource.Numeric valuesSource;
private final DocValueFormat formatter;
private final double interval, offset;
private final BucketOrder order;
private final boolean keyed;
private final long minDocCount;
private final double minBound, maxBound;
private final LongHash bucketOrds;
HistogramAggregator(String name, AggregatorFactories factories, double interval, double offset,
BucketOrder order, boolean keyed, long minDocCount, double minBound, double maxBound,
@Nullable ValuesSource.Numeric valuesSource, DocValueFormat formatter,
SearchContext context, Aggregator parent,
List<PipelineAggregator> pipelineAggregators, Map<String, Object> metaData) throws IOException {
super(name, factories, context, parent, pipelineAggregators, metaData);
if (interval <= 0) {
throw new IllegalArgumentException("interval must be positive, got: " + interval);
}
this.interval = interval;
this.offset = offset;
this.order = InternalOrder.validate(order, this);
this.keyed = keyed;
this.minDocCount = minDocCount;
this.minBound = minBound;
this.maxBound = maxBound;
this.valuesSource = valuesSource;
this.formatter = formatter;
bucketOrds = new LongHash(1, context.bigArrays());
}
@Override
public boolean needsScores() {
return (valuesSource != null && valuesSource.needsScores()) || super.needsScores();
}
@Override
public LeafBucketCollector getLeafCollector(LeafReaderContext ctx,
final LeafBucketCollector sub) throws IOException {
if (valuesSource == null) {
return LeafBucketCollector.NO_OP_COLLECTOR;
}
final SortedNumericDoubleValues values = valuesSource.doubleValues(ctx);
return new LeafBucketCollectorBase(sub, values) {
@Override
public void collect(int doc, long bucket) throws IOException {
assert bucket == 0;
if (values.advanceExact(doc)) {
final int valuesCount = values.docValueCount();
double previousKey = Double.NEGATIVE_INFINITY;
for (int i = 0; i < valuesCount; ++i) {
double value = values.nextValue();
double key = Math.floor((value - offset) / interval);
assert key >= previousKey;
if (key == previousKey) {
continue;
}
long bucketOrd = bucketOrds.add(Double.doubleToLongBits(key));
if (bucketOrd < 0) { // already seen
bucketOrd = -1 - bucketOrd;
collectExistingBucket(sub, doc, bucketOrd);
} else {
collectBucket(sub, doc, bucketOrd);
}
previousKey = key;
}
}
}
};
}
@Override
public InternalAggregation buildAggregation(long bucket) throws IOException {
assert bucket == 0;
List<InternalHistogram.Bucket> buckets = new ArrayList<>((int) bucketOrds.size());
for (long i = 0; i < bucketOrds.size(); i++) {
double roundKey = Double.longBitsToDouble(bucketOrds.get(i));
double key = roundKey * interval + offset;
buckets.add(new InternalHistogram.Bucket(key, bucketDocCount(i), keyed, formatter, bucketAggregations(i)));
}
// the contract of the histogram aggregation is that shards must return buckets ordered by key in ascending order
CollectionUtil.introSort(buckets, BucketOrder.key(true).comparator(this));
EmptyBucketInfo emptyBucketInfo = null;
if (minDocCount == 0) {
emptyBucketInfo = new EmptyBucketInfo(interval, offset, minBound, maxBound, buildEmptySubAggregations());
}
return new InternalHistogram(name, buckets, order, minDocCount, emptyBucketInfo, formatter, keyed, pipelineAggregators(), metaData());
}
@Override
public InternalAggregation buildEmptyAggregation() {
EmptyBucketInfo emptyBucketInfo = null;
if (minDocCount == 0) {
emptyBucketInfo = new EmptyBucketInfo(interval, offset, minBound, maxBound, buildEmptySubAggregations());
}
return new InternalHistogram(name, Collections.emptyList(), order, minDocCount, emptyBucketInfo, formatter, keyed, pipelineAggregators(), metaData());
}
@Override
public void doClose() {
Releasables.close(bucketOrds);
}
}