/*
* Licensed 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 com.facebook.presto.operator.aggregation;
import com.facebook.presto.bytecode.DynamicClassLoader;
import com.facebook.presto.metadata.BoundVariables;
import com.facebook.presto.metadata.FunctionRegistry;
import com.facebook.presto.metadata.SqlAggregationFunction;
import com.facebook.presto.operator.aggregation.state.KeyValuePairStateSerializer;
import com.facebook.presto.operator.aggregation.state.KeyValuePairsState;
import com.facebook.presto.operator.aggregation.state.KeyValuePairsStateFactory;
import com.facebook.presto.spi.block.Block;
import com.facebook.presto.spi.block.BlockBuilder;
import com.facebook.presto.spi.type.StandardTypes;
import com.facebook.presto.spi.type.Type;
import com.facebook.presto.spi.type.TypeManager;
import com.facebook.presto.spi.type.TypeSignatureParameter;
import com.facebook.presto.type.MapType;
import com.google.common.collect.ImmutableList;
import java.lang.invoke.MethodHandle;
import java.util.List;
import static com.facebook.presto.metadata.Signature.comparableTypeParameter;
import static com.facebook.presto.metadata.Signature.typeVariable;
import static com.facebook.presto.operator.aggregation.AggregationMetadata.ParameterMetadata;
import static com.facebook.presto.operator.aggregation.AggregationMetadata.ParameterMetadata.ParameterType.INPUT_CHANNEL;
import static com.facebook.presto.operator.aggregation.AggregationMetadata.ParameterMetadata.ParameterType.STATE;
import static com.facebook.presto.operator.aggregation.AggregationUtils.generateAggregationName;
import static com.facebook.presto.spi.type.TypeSignature.parseTypeSignature;
import static com.facebook.presto.util.Reflection.methodHandle;
import static com.google.common.collect.ImmutableList.toImmutableList;
public class MapUnionAggregation
extends SqlAggregationFunction
{
public static final MapUnionAggregation MAP_UNION = new MapUnionAggregation();
public static final String NAME = "map_union";
private static final MethodHandle OUTPUT_FUNCTION = methodHandle(MapUnionAggregation.class, "output", KeyValuePairsState.class, BlockBuilder.class);
private static final MethodHandle INPUT_FUNCTION = methodHandle(MapUnionAggregation.class, "input", Type.class, Type.class, KeyValuePairsState.class, Block.class);
private static final MethodHandle COMBINE_FUNCTION = methodHandle(MapUnionAggregation.class, "combine", KeyValuePairsState.class, KeyValuePairsState.class);
public MapUnionAggregation()
{
super(NAME, ImmutableList.of(comparableTypeParameter("K"), typeVariable("V")), ImmutableList.of(), parseTypeSignature("map<K,V>"), ImmutableList.of(parseTypeSignature("map<K,V>")));
}
@Override
public String getDescription()
{
return "Aggregate all the maps into a single map";
}
@Override
public InternalAggregationFunction specialize(BoundVariables boundVariables, int arity, TypeManager typeManager, FunctionRegistry functionRegistry)
{
Type keyType = boundVariables.getTypeVariable("K");
Type valueType = boundVariables.getTypeVariable("V");
MapType outputType = (MapType) typeManager.getParameterizedType(StandardTypes.MAP, ImmutableList.of(
TypeSignatureParameter.of(keyType.getTypeSignature()),
TypeSignatureParameter.of(valueType.getTypeSignature())));
return generateAggregation(keyType, valueType, outputType);
}
private static InternalAggregationFunction generateAggregation(Type keyType, Type valueType, MapType outputType)
{
DynamicClassLoader classLoader = new DynamicClassLoader(MapUnionAggregation.class.getClassLoader());
List<Type> inputTypes = ImmutableList.of(outputType);
KeyValuePairStateSerializer stateSerializer = new KeyValuePairStateSerializer(outputType);
Type intermediateType = stateSerializer.getSerializedType();
AggregationMetadata metadata = new AggregationMetadata(
generateAggregationName(NAME, outputType.getTypeSignature(), inputTypes.stream().map(Type::getTypeSignature).collect(toImmutableList())),
createInputParameterMetadata(outputType),
INPUT_FUNCTION.bindTo(keyType).bindTo(valueType),
COMBINE_FUNCTION,
OUTPUT_FUNCTION,
KeyValuePairsState.class,
stateSerializer,
new KeyValuePairsStateFactory(keyType, valueType),
outputType);
GenericAccumulatorFactoryBinder factory = AccumulatorCompiler.generateAccumulatorFactoryBinder(metadata, classLoader);
return new InternalAggregationFunction(NAME, inputTypes, intermediateType, outputType, true, factory);
}
private static List<ParameterMetadata> createInputParameterMetadata(Type inputType)
{
return ImmutableList.of(
new ParameterMetadata(STATE),
new ParameterMetadata(INPUT_CHANNEL, inputType));
}
public static void input(Type keyType, Type valueType, KeyValuePairsState state, Block value)
{
KeyValuePairs pairs = state.get();
if (pairs == null) {
pairs = new KeyValuePairs(keyType, valueType);
state.set(pairs);
}
long startSize = pairs.estimatedInMemorySize();
for (int i = 0; i < value.getPositionCount(); i += 2) {
pairs.add(value, value, i, i + 1);
}
state.addMemoryUsage(pairs.estimatedInMemorySize() - startSize);
}
public static void combine(KeyValuePairsState state, KeyValuePairsState otherState)
{
MapAggregationFunction.combine(state, otherState);
}
public static void output(KeyValuePairsState state, BlockBuilder out)
{
MapAggregationFunction.output(state, out);
}
}