/*
* Druid - a distributed column store.
* Copyright (C) 2012, 2013 Metamarkets Group Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package io.druid.query.topn;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.google.common.base.Charsets;
import com.google.common.base.Preconditions;
import com.google.common.base.Predicate;
import com.google.common.collect.Iterables;
import io.druid.query.aggregation.AggregatorFactory;
import io.druid.query.aggregation.PostAggregator;
import io.druid.query.dimension.DimensionSpec;
import org.joda.time.DateTime;
import java.nio.ByteBuffer;
import java.util.Comparator;
import java.util.List;
/**
*/
public class NumericTopNMetricSpec implements TopNMetricSpec
{
private static final byte CACHE_TYPE_ID = 0x0;
private final String metric;
@JsonCreator
public NumericTopNMetricSpec(
@JsonProperty("metric") String metric
)
{
this.metric = metric;
}
@Override
public void verifyPreconditions(List<AggregatorFactory> aggregatorSpecs, List<PostAggregator> postAggregatorSpecs)
{
Preconditions.checkNotNull(metric, "metric can't be null");
Preconditions.checkNotNull(aggregatorSpecs, "aggregations cannot be null");
Preconditions.checkArgument(aggregatorSpecs.size() > 0, "Must have at least one AggregatorFactory");
final AggregatorFactory aggregator = Iterables.tryFind(
aggregatorSpecs,
new Predicate<AggregatorFactory>()
{
@Override
public boolean apply(AggregatorFactory input)
{
return input.getName().equals(metric);
}
}
).orNull();
final PostAggregator postAggregator = Iterables.tryFind(
postAggregatorSpecs,
new Predicate<PostAggregator>()
{
@Override
public boolean apply(PostAggregator input)
{
return input.getName().equals(metric);
}
}
).orNull();
Preconditions.checkArgument(
aggregator != null || postAggregator != null,
"Must have an AggregatorFactory or PostAggregator for metric[%s], gave[%s] and [%s]",
metric,
aggregatorSpecs,
postAggregatorSpecs
);
}
@JsonProperty
public String getMetric()
{
return metric;
}
@Override
public Comparator getComparator(List<AggregatorFactory> aggregatorSpecs, List<PostAggregator> postAggregatorSpecs)
{
Comparator comp = null;
for (AggregatorFactory factory : aggregatorSpecs) {
if (metric.equals(factory.getName())) {
comp = factory.getComparator();
break;
}
}
for (PostAggregator pf : postAggregatorSpecs) {
if (metric.equals(pf.getName())) {
comp = pf.getComparator();
break;
}
}
return comp;
}
@Override
public TopNResultBuilder getResultBuilder(
DateTime timestamp,
DimensionSpec dimSpec,
int threshold,
Comparator comparator,
List<AggregatorFactory> aggFactories,
List<PostAggregator> postAggs
)
{
return new TopNNumericResultBuilder(timestamp, dimSpec, metric, threshold, comparator, aggFactories, postAggs);
}
@Override
public byte[] getCacheKey()
{
byte[] metricBytes = metric.getBytes(Charsets.UTF_8);
return ByteBuffer.allocate(1 + metricBytes.length)
.put(CACHE_TYPE_ID)
.put(metricBytes)
.array();
}
@Override
public <T> TopNMetricSpecBuilder<T> configureOptimizer(TopNMetricSpecBuilder<T> builder)
{
return builder;
}
@Override
public void initTopNAlgorithmSelector(TopNAlgorithmSelector selector)
{
selector.setAggregateTopNMetricFirst(true);
}
@Override
public String getMetricName(DimensionSpec dimSpec)
{
return metric;
}
@Override
public boolean canBeOptimizedUnordered()
{
return true;
}
@Override
public String toString()
{
return "NumericTopNMetricSpec{" +
"metric='" + metric + '\'' +
'}';
}
@Override
public boolean equals(Object o)
{
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
NumericTopNMetricSpec that = (NumericTopNMetricSpec) o;
if (metric != null ? !metric.equals(that.metric) : that.metric != null) return false;
return true;
}
@Override
public int hashCode()
{
return metric != null ? metric.hashCode() : 0;
}
}