/*
* 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.spi.block.Block;
import com.facebook.presto.spi.block.BlockBuilder;
import com.facebook.presto.spi.block.BlockBuilderStatus;
import com.facebook.presto.spi.function.AccumulatorStateSerializer;
import com.facebook.presto.spi.type.Type;
import com.facebook.presto.type.ArrayType;
public class ArrayAggregationStateSerializer
implements AccumulatorStateSerializer<ArrayAggregationState>
{
private final Type elementType;
private final Type arrayType;
public ArrayAggregationStateSerializer(Type elementType)
{
this.elementType = elementType;
this.arrayType = new ArrayType(elementType);
}
@Override
public Type getSerializedType()
{
return arrayType;
}
@Override
public void serialize(ArrayAggregationState state, BlockBuilder out)
{
if (state.getBlockBuilder() == null) {
out.appendNull();
}
else {
Block stateBlock = state.getBlockBuilder().build();
arrayType.writeObject(out, stateBlock);
}
}
@Override
public void deserialize(Block block, int index, ArrayAggregationState state)
{
Block stateBlock = (Block) arrayType.getObject(block, index);
int positionCount = stateBlock.getPositionCount();
BlockBuilder blockBuilder = elementType.createBlockBuilder(new BlockBuilderStatus(), positionCount);
for (int i = 0; i < positionCount; i++) {
elementType.appendTo(stateBlock, i, blockBuilder);
}
state.setBlockBuilder(blockBuilder);
}
}