/*
* 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.ExceededMemoryLimitException;
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.MultiKeyValuePairStateSerializer;
import com.facebook.presto.operator.aggregation.state.MultiKeyValuePairsState;
import com.facebook.presto.operator.aggregation.state.MultiKeyValuePairsStateFactory;
import com.facebook.presto.spi.PrestoException;
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.ArrayType;
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.BLOCK_INDEX;
import static com.facebook.presto.operator.aggregation.AggregationMetadata.ParameterMetadata.ParameterType.BLOCK_INPUT_CHANNEL;
import static com.facebook.presto.operator.aggregation.AggregationMetadata.ParameterMetadata.ParameterType.NULLABLE_BLOCK_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.StandardErrorCode.INVALID_FUNCTION_ARGUMENT;
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;
import static java.lang.String.format;
public class MultimapAggregationFunction
extends SqlAggregationFunction
{
public static final MultimapAggregationFunction MULTIMAP_AGG = new MultimapAggregationFunction();
public static final String NAME = "multimap_agg";
private static final MethodHandle OUTPUT_FUNCTION = methodHandle(MultimapAggregationFunction.class, "output", MultiKeyValuePairsState.class, BlockBuilder.class);
private static final MethodHandle INPUT_FUNCTION = methodHandle(MultimapAggregationFunction.class, "input", MultiKeyValuePairsState.class, Block.class, Block.class, int.class);
private static final MethodHandle COMBINE_FUNCTION = methodHandle(MultimapAggregationFunction.class, "combine", MultiKeyValuePairsState.class, MultiKeyValuePairsState.class);
public MultimapAggregationFunction()
{
super(NAME,
ImmutableList.of(comparableTypeParameter("K"), typeVariable("V")),
ImmutableList.of(),
parseTypeSignature("map(K,array(V))"),
ImmutableList.of(parseTypeSignature("K"), parseTypeSignature("V")));
}
@Override
public String getDescription()
{
return "Aggregates all the rows (key/value pairs) into a single multimap";
}
@Override
public InternalAggregationFunction specialize(BoundVariables boundVariables, int arity, TypeManager typeManager, FunctionRegistry functionRegistry)
{
Type keyType = boundVariables.getTypeVariable("K");
Type valueType = boundVariables.getTypeVariable("V");
Type outputType = typeManager.getParameterizedType(StandardTypes.MAP, ImmutableList.of(
TypeSignatureParameter.of(keyType.getTypeSignature()),
TypeSignatureParameter.of(new ArrayType(valueType).getTypeSignature())));
return generateAggregation(keyType, valueType, outputType);
}
private static InternalAggregationFunction generateAggregation(Type keyType, Type valueType, Type outputType)
{
DynamicClassLoader classLoader = new DynamicClassLoader(MultimapAggregationFunction.class.getClassLoader());
List<Type> inputTypes = ImmutableList.of(keyType, valueType);
MultiKeyValuePairStateSerializer stateSerializer = new MultiKeyValuePairStateSerializer(keyType, valueType);
Type intermediateType = stateSerializer.getSerializedType();
AggregationMetadata metadata = new AggregationMetadata(
generateAggregationName(NAME, outputType.getTypeSignature(), inputTypes.stream().map(Type::getTypeSignature).collect(toImmutableList())),
createInputParameterMetadata(keyType, valueType),
INPUT_FUNCTION,
COMBINE_FUNCTION,
OUTPUT_FUNCTION,
MultiKeyValuePairsState.class,
stateSerializer,
new MultiKeyValuePairsStateFactory(keyType, valueType),
outputType);
GenericAccumulatorFactoryBinder factory = AccumulatorCompiler.generateAccumulatorFactoryBinder(metadata, classLoader);
return new InternalAggregationFunction(NAME, inputTypes, intermediateType, outputType, true, factory);
}
private static List<ParameterMetadata> createInputParameterMetadata(Type keyType, Type valueType)
{
return ImmutableList.of(new ParameterMetadata(STATE),
new ParameterMetadata(BLOCK_INPUT_CHANNEL, keyType),
new ParameterMetadata(NULLABLE_BLOCK_INPUT_CHANNEL, valueType),
new ParameterMetadata(BLOCK_INDEX));
}
public static void input(MultiKeyValuePairsState state, Block key, Block value, int position)
{
MultiKeyValuePairs pairs = state.get();
if (pairs == null) {
pairs = new MultiKeyValuePairs(state.getKeyType(), state.getValueType());
state.set(pairs);
}
long startSize = pairs.estimatedInMemorySize();
try {
pairs.add(key, value, position, position);
}
catch (ExceededMemoryLimitException e) {
throw new PrestoException(INVALID_FUNCTION_ARGUMENT, format("The result of map_agg may not exceed %s", e.getMaxMemory()));
}
state.addMemoryUsage(pairs.estimatedInMemorySize() - startSize);
}
public static void combine(MultiKeyValuePairsState state, MultiKeyValuePairsState otherState)
{
if (state.get() != null && otherState.get() != null) {
Block keys = otherState.get().getKeys();
Block values = otherState.get().getValues();
MultiKeyValuePairs pairs = state.get();
long startSize = pairs.estimatedInMemorySize();
for (int i = 0; i < keys.getPositionCount(); i++) {
try {
pairs.add(keys, values, i, i);
}
catch (ExceededMemoryLimitException e) {
throw new PrestoException(INVALID_FUNCTION_ARGUMENT, format("The result of map_agg may not exceed %s", e.getMaxMemory()));
}
}
state.addMemoryUsage(pairs.estimatedInMemorySize() - startSize);
}
else if (state.get() == null) {
state.set(otherState.get());
}
}
public static void output(MultiKeyValuePairsState state, BlockBuilder out)
{
MultiKeyValuePairs pairs = state.get();
if (pairs == null) {
out.appendNull();
}
else {
Block block = pairs.toMultimapNativeEncoding();
out.writeObject(block);
out.closeEntry();
}
}
}