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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
* "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
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package org.elasticsearch.search.aggregations.bucket.geogrid;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.SortedNumericDocValues;
import org.elasticsearch.common.lease.Releasables;
import org.elasticsearch.common.util.LongHash;
import org.elasticsearch.search.aggregations.Aggregator;
import org.elasticsearch.search.aggregations.AggregatorFactories;
import org.elasticsearch.search.aggregations.InternalAggregations;
import org.elasticsearch.search.aggregations.bucket.BucketsAggregator;
import org.elasticsearch.search.aggregations.support.AggregationContext;
import org.elasticsearch.search.aggregations.support.ValuesSource;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collections;
import java.util.Map;
/**
* Aggregates data expressed as GeoHash longs (for efficiency's sake) but formats results as Geohash strings.
*
*/
public class GeoHashGridAggregator extends BucketsAggregator {
private static final int INITIAL_CAPACITY = 50; // TODO sizing
private final int requiredSize;
private final int shardSize;
private final ValuesSource.Numeric valuesSource;
private final LongHash bucketOrds;
private SortedNumericDocValues values;
public GeoHashGridAggregator(String name, AggregatorFactories factories, ValuesSource.Numeric valuesSource,
int requiredSize, int shardSize, AggregationContext aggregationContext, Aggregator parent, Map<String, Object> metaData) {
super(name, BucketAggregationMode.PER_BUCKET, factories, INITIAL_CAPACITY, aggregationContext, parent, metaData);
this.valuesSource = valuesSource;
this.requiredSize = requiredSize;
this.shardSize = shardSize;
bucketOrds = new LongHash(INITIAL_CAPACITY, aggregationContext.bigArrays());
}
@Override
public boolean shouldCollect() {
return true;
}
@Override
public void setNextReader(LeafReaderContext reader) {
values = valuesSource.longValues();
}
@Override
public void collect(int doc, long owningBucketOrdinal) throws IOException {
assert owningBucketOrdinal == 0;
values.setDocument(doc);
final int valuesCount = values.count();
for (int i = 0; i < valuesCount; ++i) {
final long val = values.valueAt(i);
long bucketOrdinal = bucketOrds.add(val);
if (bucketOrdinal < 0) { // already seen
bucketOrdinal = - 1 - bucketOrdinal;
collectExistingBucket(doc, bucketOrdinal);
} else {
collectBucket(doc, bucketOrdinal);
}
}
}
// private impl that stores a bucket ord. This allows for computing the aggregations lazily.
static class OrdinalBucket extends InternalGeoHashGrid.Bucket {
long bucketOrd;
public OrdinalBucket() {
super(0, 0, (InternalAggregations) null);
}
}
@Override
public InternalGeoHashGrid buildAggregation(long owningBucketOrdinal) {
assert owningBucketOrdinal == 0;
final int size = (int) Math.min(bucketOrds.size(), shardSize);
InternalGeoHashGrid.BucketPriorityQueue ordered = new InternalGeoHashGrid.BucketPriorityQueue(size);
OrdinalBucket spare = null;
for (long i = 0; i < bucketOrds.size(); i++) {
if (spare == null) {
spare = new OrdinalBucket();
}
spare.geohashAsLong = bucketOrds.get(i);
spare.docCount = bucketDocCount(i);
spare.bucketOrd = i;
spare = (OrdinalBucket) ordered.insertWithOverflow(spare);
}
final InternalGeoHashGrid.Bucket[] list = new InternalGeoHashGrid.Bucket[ordered.size()];
for (int i = ordered.size() - 1; i >= 0; --i) {
final OrdinalBucket bucket = (OrdinalBucket) ordered.pop();
bucket.aggregations = bucketAggregations(bucket.bucketOrd);
list[i] = bucket;
}
return new InternalGeoHashGrid(name, requiredSize, Arrays.asList(list), getMetaData());
}
@Override
public InternalGeoHashGrid buildEmptyAggregation() {
return new InternalGeoHashGrid(name, requiredSize, Collections.<InternalGeoHashGrid.Bucket>emptyList(), getMetaData());
}
@Override
public void doClose() {
Releasables.close(bucketOrds);
}
}