AbstractMinMaxNAggregationFunction.java
/*
* 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.common.block.Block;
import com.facebook.presto.common.block.BlockBuilder;
import com.facebook.presto.common.type.ArrayType;
import com.facebook.presto.common.type.StandardTypes;
import com.facebook.presto.common.type.Type;
import com.facebook.presto.metadata.BoundVariables;
import com.facebook.presto.metadata.FunctionAndTypeManager;
import com.facebook.presto.metadata.SqlAggregationFunction;
import com.facebook.presto.operator.aggregation.state.MinMaxNState;
import com.facebook.presto.operator.aggregation.state.MinMaxNStateFactory;
import com.facebook.presto.operator.aggregation.state.MinMaxNStateSerializer;
import com.facebook.presto.spi.PrestoException;
import com.facebook.presto.spi.function.aggregation.Accumulator;
import com.facebook.presto.spi.function.aggregation.AggregationMetadata;
import com.facebook.presto.spi.function.aggregation.AggregationMetadata.AccumulatorStateDescriptor;
import com.facebook.presto.spi.function.aggregation.GroupedAccumulator;
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.common.type.BigintType.BIGINT;
import static com.facebook.presto.common.type.TypeSignature.parseTypeSignature;
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.function.Signature.orderableTypeParameter;
import static com.facebook.presto.spi.function.aggregation.AggregationMetadata.ParameterMetadata;
import static com.facebook.presto.spi.function.aggregation.AggregationMetadata.ParameterMetadata.ParameterType.BLOCK_INDEX;
import static com.facebook.presto.spi.function.aggregation.AggregationMetadata.ParameterMetadata.ParameterType.BLOCK_INPUT_CHANNEL;
import static com.facebook.presto.spi.function.aggregation.AggregationMetadata.ParameterMetadata.ParameterType.INPUT_CHANNEL;
import static com.facebook.presto.spi.function.aggregation.AggregationMetadata.ParameterMetadata.ParameterType.STATE;
import static com.facebook.presto.util.Failures.checkCondition;
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 AbstractMinMaxNAggregationFunction
extends SqlAggregationFunction
{
private static final MethodHandle INPUT_FUNCTION = methodHandle(AbstractMinMaxNAggregationFunction.class, "input", BlockComparator.class, Type.class, MinMaxNState.class, Block.class, long.class, int.class);
private static final MethodHandle COMBINE_FUNCTION = methodHandle(AbstractMinMaxNAggregationFunction.class, "combine", MinMaxNState.class, MinMaxNState.class);
private static final MethodHandle OUTPUT_FUNCTION = methodHandle(AbstractMinMaxNAggregationFunction.class, "output", ArrayType.class, MinMaxNState.class, BlockBuilder.class);
private static final long MAX_NUMBER_OF_VALUES = 10_000;
private final Function<Type, BlockComparator> typeToComparator;
protected AbstractMinMaxNAggregationFunction(String name, Function<Type, BlockComparator> typeToComparator)
{
super(name,
ImmutableList.of(orderableTypeParameter("E")),
ImmutableList.of(),
parseTypeSignature("array(E)"),
ImmutableList.of(parseTypeSignature("E"), parseTypeSignature(StandardTypes.BIGINT)));
requireNonNull(typeToComparator);
this.typeToComparator = typeToComparator;
}
@Override
public BuiltInAggregationFunctionImplementation specialize(BoundVariables boundVariables, int arity, FunctionAndTypeManager functionAndTypeManager)
{
Type type = boundVariables.getTypeVariable("E");
return generateAggregation(type);
}
protected BuiltInAggregationFunctionImplementation generateAggregation(Type type)
{
DynamicClassLoader classLoader = new DynamicClassLoader(AbstractMinMaxNAggregationFunction.class.getClassLoader());
BlockComparator comparator = typeToComparator.apply(type);
List<Type> inputTypes = ImmutableList.of(type, BIGINT);
MinMaxNStateSerializer stateSerializer = new MinMaxNStateSerializer(comparator, type);
Type intermediateType = stateSerializer.getSerializedType();
ArrayType outputType = new ArrayType(type);
List<ParameterMetadata> inputParameterMetadata = ImmutableList.of(
new ParameterMetadata(STATE),
new ParameterMetadata(BLOCK_INPUT_CHANNEL, type),
new ParameterMetadata(INPUT_CHANNEL, BIGINT),
new ParameterMetadata(BLOCK_INDEX));
AggregationMetadata metadata = new AggregationMetadata(
generateAggregationName(getSignature().getNameSuffix(), type.getTypeSignature(), inputTypes.stream().map(Type::getTypeSignature).collect(toImmutableList())),
inputParameterMetadata,
INPUT_FUNCTION.bindTo(comparator).bindTo(type),
COMBINE_FUNCTION,
OUTPUT_FUNCTION.bindTo(outputType),
ImmutableList.of(new AccumulatorStateDescriptor(
MinMaxNState.class,
stateSerializer,
new MinMaxNStateFactory())),
outputType);
Class<? extends Accumulator> accumulatorClass = AccumulatorCompiler.generateAccumulatorClass(
Accumulator.class,
metadata,
classLoader);
Class<? extends GroupedAccumulator> groupedAccumulatorClass = AccumulatorCompiler.generateAccumulatorClass(
GroupedAccumulator.class,
metadata,
classLoader);
return new BuiltInAggregationFunctionImplementation(getSignature().getNameSuffix(), inputTypes, ImmutableList.of(intermediateType), outputType,
true, false, metadata, accumulatorClass, groupedAccumulatorClass);
}
public static void input(BlockComparator comparator, Type type, MinMaxNState state, Block block, long n, int blockIndex)
{
TypedHeap heap = state.getTypedHeap();
if (heap == null) {
if (n <= 0) {
throw new PrestoException(INVALID_FUNCTION_ARGUMENT, "second argument of max_n/min_n must be positive");
}
checkCondition(n <= MAX_NUMBER_OF_VALUES, INVALID_FUNCTION_ARGUMENT, "second argument of max_n/min_n must be less than or equal to %s; found %s", MAX_NUMBER_OF_VALUES, n);
heap = new TypedHeap(comparator, type, toIntExact(n));
state.setTypedHeap(heap);
}
else {
checkCondition(n == heap.getCapacity(), INVALID_FUNCTION_ARGUMENT, "Count argument is not constant: found multiple values [%s, %s]", n, heap.getCapacity());
}
long startSize = heap.getEstimatedSize();
heap.add(block, blockIndex);
state.addMemoryUsage(heap.getEstimatedSize() - startSize);
}
public static void combine(MinMaxNState state, MinMaxNState otherState)
{
TypedHeap otherHeap = otherState.getTypedHeap();
if (otherHeap == null) {
return;
}
TypedHeap heap = state.getTypedHeap();
if (heap == null) {
state.setTypedHeap(otherHeap);
return;
}
checkCondition(otherHeap.getCapacity() == heap.getCapacity(), INVALID_FUNCTION_ARGUMENT, "Count argument is not constant: found multiple values [%s, %s]: %s", otherHeap.getCapacity(), heap.getCapacity());
long startSize = heap.getEstimatedSize();
heap.addAll(otherHeap);
state.addMemoryUsage(heap.getEstimatedSize() - startSize);
}
public static void output(ArrayType outputType, MinMaxNState state, BlockBuilder out)
{
TypedHeap heap = state.getTypedHeap();
if (heap == null || heap.isEmpty()) {
out.appendNull();
return;
}
Type elementType = outputType.getElementType();
BlockBuilder reversedBlockBuilder = elementType.createBlockBuilder(null, heap.getCapacity());
long startSize = heap.getEstimatedSize();
heap.popAll(reversedBlockBuilder);
state.addMemoryUsage(heap.getEstimatedSize() - startSize);
BlockBuilder arrayBlockBuilder = out.beginBlockEntry();
for (int i = reversedBlockBuilder.getPositionCount() - 1; i >= 0; i--) {
elementType.appendTo(reversedBlockBuilder, i, arrayBlockBuilder);
}
heap.addAll(reversedBlockBuilder);
out.closeEntry();
}
}