Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance. Project price only 1 $
You can buy this project and download/modify it how often you want.
/*
* Licensed to Metamarkets Group Inc. (Metamarkets) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Metamarkets 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 io.druid.query.topn;
import io.druid.collections.NonBlockingPool;
import io.druid.java.util.common.ISE;
import io.druid.java.util.common.Pair;
import io.druid.query.ColumnSelectorPlus;
import io.druid.query.aggregation.AggregatorFactory;
import io.druid.query.aggregation.AggregatorUtil;
import io.druid.query.aggregation.PostAggregator;
import io.druid.segment.Capabilities;
import io.druid.segment.Cursor;
import javax.annotation.Nullable;
import java.nio.ByteBuffer;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
/**
*/
public class AggregateTopNMetricFirstAlgorithm implements TopNAlgorithm
{
private final Capabilities capabilities;
private final TopNQuery query;
private final NonBlockingPool bufferPool;
public AggregateTopNMetricFirstAlgorithm(
Capabilities capabilities,
TopNQuery query,
NonBlockingPool bufferPool
)
{
this.capabilities = capabilities;
this.query = query;
this.bufferPool = bufferPool;
}
@Override
public TopNParams makeInitParams(
ColumnSelectorPlus selectorPlus, Cursor cursor
)
{
return new TopNParams(
selectorPlus,
cursor,
Integer.MAX_VALUE
);
}
@Override
public void run(
TopNParams params,
TopNResultBuilder resultBuilder,
int[] ints,
@Nullable TopNQueryMetrics queryMetrics
)
{
final String metric = query.getTopNMetricSpec().getMetricName(query.getDimensionSpec());
Pair, List> condensedAggPostAggPair = AggregatorUtil.condensedAggregators(
query.getAggregatorSpecs(),
query.getPostAggregatorSpecs(),
metric
);
if (condensedAggPostAggPair.lhs.isEmpty() && condensedAggPostAggPair.rhs.isEmpty()) {
throw new ISE("WTF! Can't find the metric to do topN over?");
}
// Run topN for only a single metric
TopNQuery singleMetricQuery = new TopNQueryBuilder(query)
.aggregators(condensedAggPostAggPair.lhs)
.postAggregators(condensedAggPostAggPair.rhs)
.build();
final TopNResultBuilder singleMetricResultBuilder = BaseTopNAlgorithm.makeResultBuilder(params, singleMetricQuery);
PooledTopNAlgorithm singleMetricAlgo = new PooledTopNAlgorithm(capabilities, singleMetricQuery, bufferPool);
PooledTopNAlgorithm.PooledTopNParams singleMetricParam = null;
int[] dimValSelector = null;
try {
singleMetricParam = singleMetricAlgo.makeInitParams(params.getSelectorPlus(), params.getCursor());
singleMetricAlgo.run(
singleMetricParam,
singleMetricResultBuilder,
null,
null // Don't collect metrics during the preparation run.
);
// Get only the topN dimension values
dimValSelector = getDimValSelectorForTopNMetric(singleMetricParam, singleMetricResultBuilder);
}
finally {
singleMetricAlgo.cleanup(singleMetricParam);
}
PooledTopNAlgorithm allMetricAlgo = new PooledTopNAlgorithm(capabilities, query, bufferPool);
PooledTopNAlgorithm.PooledTopNParams allMetricsParam = null;
try {
// Run topN for all metrics for top N dimension values
allMetricsParam = allMetricAlgo.makeInitParams(params.getSelectorPlus(), params.getCursor());
allMetricAlgo.run(
allMetricsParam,
resultBuilder,
dimValSelector,
queryMetrics
);
}
finally {
allMetricAlgo.cleanup(allMetricsParam);
}
}
@Override
public void cleanup(TopNParams params)
{
}
private int[] getDimValSelectorForTopNMetric(TopNParams params, TopNResultBuilder resultBuilder)
{
if (params.getCardinality() < 0) {
throw new UnsupportedOperationException("Cannot operate on a dimension with unknown cardinality");
}
int[] dimValSelector = new int[params.getCardinality()];
Arrays.fill(dimValSelector, SKIP_POSITION_VALUE);
Iterator dimValIter = resultBuilder.getTopNIterator();
while (dimValIter.hasNext()) {
int dimValIndex = (Integer) dimValIter.next().getDimValIndex();
dimValSelector[dimValIndex] = INIT_POSITION_VALUE;
}
return dimValSelector;
}
}