/*
* 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.state;
import com.facebook.presto.operator.aggregation.BlockComparator;
import com.facebook.presto.operator.aggregation.TypedHeap;
import com.facebook.presto.spi.block.Block;
import com.facebook.presto.spi.block.BlockBuilder;
import com.facebook.presto.spi.function.AccumulatorStateSerializer;
import com.facebook.presto.spi.type.Type;
import com.facebook.presto.type.ArrayType;
import com.facebook.presto.type.RowType;
import com.google.common.collect.ImmutableList;
import java.util.Optional;
import static com.facebook.presto.spi.type.BigintType.BIGINT;
import static java.lang.Math.toIntExact;
public class MinMaxNStateSerializer
implements AccumulatorStateSerializer<MinMaxNState>
{
private final BlockComparator blockComparator;
private final Type elementType;
private final ArrayType arrayType;
private final Type serializedType;
public MinMaxNStateSerializer(BlockComparator blockComparator, Type elementType)
{
this.blockComparator = blockComparator;
this.elementType = elementType;
this.arrayType = new ArrayType(elementType);
this.serializedType = new RowType(ImmutableList.of(BIGINT, arrayType), Optional.empty());
}
@Override
public Type getSerializedType()
{
return serializedType;
}
@Override
public void serialize(MinMaxNState state, BlockBuilder out)
{
TypedHeap heap = state.getTypedHeap();
if (heap == null) {
out.appendNull();
return;
}
BlockBuilder blockBuilder = out.beginBlockEntry();
BIGINT.writeLong(blockBuilder, heap.getCapacity());
BlockBuilder elements = blockBuilder.beginBlockEntry();
heap.writeAll(elements);
blockBuilder.closeEntry();
out.closeEntry();
}
@Override
public void deserialize(Block block, int index, MinMaxNState state)
{
Block currentBlock = (Block) serializedType.getObject(block, index);
int capacity = toIntExact(BIGINT.getLong(currentBlock, 0));
Block heapBlock = arrayType.getObject(currentBlock, 1);
TypedHeap heap = new TypedHeap(blockComparator, elementType, capacity);
heap.addAll(heapBlock);
state.setTypedHeap(heap);
}
}