/*
* 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.MinMaxByNState;
import com.facebook.presto.operator.aggregation.state.MinMaxByNStateFactory;
import com.facebook.presto.operator.aggregation.state.MinMaxByNStateSerializer;
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.block.BlockBuilderStatus;
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.type.ArrayType;
import com.google.common.collect.ImmutableList;
import java.lang.invoke.MethodHandle;
import java.util.List;
import java.util.function.Function;
import static com.facebook.presto.metadata.Signature.orderableTypeParameter;
import static com.facebook.presto.metadata.Signature.typeVariable;
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.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.BigintType.BIGINT;
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.Math.toIntExact;
import static java.util.Objects.requireNonNull;
public abstract class AbstractMinMaxByNAggregationFunction
extends SqlAggregationFunction
{
private static final MethodHandle INPUT_FUNCTION = methodHandle(AbstractMinMaxByNAggregationFunction.class, "input", BlockComparator.class, Type.class, Type.class, MinMaxByNState.class, Block.class, Block.class, int.class, long.class);
private static final MethodHandle COMBINE_FUNCTION = methodHandle(AbstractMinMaxByNAggregationFunction.class, "combine", MinMaxByNState.class, MinMaxByNState.class);
private static final MethodHandle OUTPUT_FUNCTION = methodHandle(AbstractMinMaxByNAggregationFunction.class, "output", ArrayType.class, MinMaxByNState.class, BlockBuilder.class);
private final String name;
private final Function<Type, BlockComparator> typeToComparator;
protected AbstractMinMaxByNAggregationFunction(String name, Function<Type, BlockComparator> typeToComparator)
{
super(name,
ImmutableList.of(typeVariable("V"), orderableTypeParameter("K")),
ImmutableList.of(),
parseTypeSignature("array(V)"),
ImmutableList.of(parseTypeSignature("V"), parseTypeSignature("K"), parseTypeSignature(StandardTypes.BIGINT)));
this.name = requireNonNull(name, "name is null");
this.typeToComparator = requireNonNull(typeToComparator, "typeToComparator is null");
}
@Override
public InternalAggregationFunction specialize(BoundVariables boundVariables, int arity, TypeManager typeManager, FunctionRegistry functionRegistry)
{
Type keyType = boundVariables.getTypeVariable("K");
Type valueType = boundVariables.getTypeVariable("V");
return generateAggregation(valueType, keyType);
}
public static void input(BlockComparator comparator, Type valueType, Type keyType, MinMaxByNState state, Block value, Block key, int blockIndex, long n)
{
TypedKeyValueHeap heap = state.getTypedKeyValueHeap();
if (heap == null) {
if (n <= 0) {
throw new PrestoException(INVALID_FUNCTION_ARGUMENT, "third argument of max_by/min_by must be a positive integer");
}
heap = new TypedKeyValueHeap(comparator, keyType, valueType, toIntExact(n));
state.setTypedKeyValueHeap(heap);
}
long startSize = heap.getEstimatedSize();
if (!key.isNull(blockIndex)) {
heap.add(key, value, blockIndex);
}
state.addMemoryUsage(heap.getEstimatedSize() - startSize);
}
public static void combine(MinMaxByNState state, MinMaxByNState otherState)
{
TypedKeyValueHeap otherHeap = otherState.getTypedKeyValueHeap();
if (otherHeap == null) {
return;
}
TypedKeyValueHeap heap = state.getTypedKeyValueHeap();
if (heap == null) {
state.setTypedKeyValueHeap(otherHeap);
return;
}
long startSize = heap.getEstimatedSize();
heap.addAll(otherHeap);
state.addMemoryUsage(heap.getEstimatedSize() - startSize);
}
public static void output(ArrayType outputType, MinMaxByNState state, BlockBuilder out)
{
TypedKeyValueHeap heap = state.getTypedKeyValueHeap();
if (heap == null || heap.isEmpty()) {
out.appendNull();
return;
}
Type elementType = outputType.getElementType();
BlockBuilder arrayBlockBuilder = out.beginBlockEntry();
BlockBuilder reversedBlockBuilder = elementType.createBlockBuilder(new BlockBuilderStatus(), heap.getCapacity());
long startSize = heap.getEstimatedSize();
heap.popAll(reversedBlockBuilder);
state.addMemoryUsage(heap.getEstimatedSize() - startSize);
for (int i = reversedBlockBuilder.getPositionCount() - 1; i >= 0; i--) {
elementType.appendTo(reversedBlockBuilder, i, arrayBlockBuilder);
}
out.closeEntry();
}
protected InternalAggregationFunction generateAggregation(Type valueType, Type keyType)
{
DynamicClassLoader classLoader = new DynamicClassLoader(AbstractMinMaxNAggregationFunction.class.getClassLoader());
BlockComparator comparator = typeToComparator.apply(keyType);
List<Type> inputTypes = ImmutableList.of(valueType, keyType, BIGINT);
MinMaxByNStateSerializer stateSerializer = new MinMaxByNStateSerializer(comparator, keyType, valueType);
Type intermediateType = stateSerializer.getSerializedType();
ArrayType outputType = new ArrayType(valueType);
List<AggregationMetadata.ParameterMetadata> inputParameterMetadata = ImmutableList.of(
new AggregationMetadata.ParameterMetadata(STATE),
new AggregationMetadata.ParameterMetadata(NULLABLE_BLOCK_INPUT_CHANNEL, valueType),
new AggregationMetadata.ParameterMetadata(BLOCK_INPUT_CHANNEL, keyType),
new AggregationMetadata.ParameterMetadata(BLOCK_INDEX),
new AggregationMetadata.ParameterMetadata(INPUT_CHANNEL, BIGINT));
AggregationMetadata metadata = new AggregationMetadata(
generateAggregationName(name, valueType.getTypeSignature(), inputTypes.stream().map(Type::getTypeSignature).collect(toImmutableList())),
inputParameterMetadata,
INPUT_FUNCTION.bindTo(comparator).bindTo(valueType).bindTo(keyType),
COMBINE_FUNCTION,
OUTPUT_FUNCTION.bindTo(outputType),
MinMaxByNState.class,
stateSerializer,
new MinMaxByNStateFactory(),
outputType);
GenericAccumulatorFactoryBinder factory = AccumulatorCompiler.generateAccumulatorFactoryBinder(metadata, classLoader);
return new InternalAggregationFunction(name, inputTypes, intermediateType, outputType, true, factory);
}
}