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A fork of the Apache Cassandra Project ready to embed Elasticsearch.
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 org.apache.cassandra.cql3.selection;
import java.nio.ByteBuffer;
import java.util.List;
import org.apache.cassandra.cql3.functions.AggregateFunction;
import org.apache.cassandra.cql3.functions.Function;
import org.apache.cassandra.cql3.selection.Selection.ResultSetBuilder;
import org.apache.cassandra.exceptions.InvalidRequestException;
final class AggregateFunctionSelector extends AbstractFunctionSelector
{
private final AggregateFunction.Aggregate aggregate;
public boolean isAggregate()
{
return true;
}
public void addInput(int protocolVersion, ResultSetBuilder rs) throws InvalidRequestException
{
// Aggregation of aggregation is not supported
for (int i = 0, m = argSelectors.size(); i < m; i++)
{
Selector s = argSelectors.get(i);
s.addInput(protocolVersion, rs);
args.set(i, s.getOutput(protocolVersion));
s.reset();
}
this.aggregate.addInput(protocolVersion, args);
}
public ByteBuffer getOutput(int protocolVersion) throws InvalidRequestException
{
return aggregate.compute(protocolVersion);
}
public void reset()
{
aggregate.reset();
}
AggregateFunctionSelector(Function fun, List argSelectors) throws InvalidRequestException
{
super((AggregateFunction) fun, argSelectors);
this.aggregate = this.fun.newAggregate();
}
}