/*
* 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.metadata.FunctionListBuilder;
import com.facebook.presto.operator.aggregation.state.NullableLongState;
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.AggregationFunction;
import com.facebook.presto.spi.function.AggregationState;
import com.facebook.presto.spi.function.CombineFunction;
import com.facebook.presto.spi.function.InputFunction;
import com.facebook.presto.spi.function.OutputFunction;
import com.facebook.presto.spi.function.SqlType;
import com.facebook.presto.spi.type.StandardTypes;
import com.google.common.collect.ImmutableList;
import org.testng.annotations.BeforeClass;
import java.util.List;
import static com.facebook.presto.spi.type.BigintType.BIGINT;
public class TestCountNullAggregation
extends AbstractTestAggregationFunction
{
@BeforeClass
public void setup()
{
functionRegistry.addFunctions(new FunctionListBuilder().aggregate(CountNull.class).getFunctions());
}
@Override
public Block[] getSequenceBlocks(int start, int length)
{
BlockBuilder blockBuilder = BIGINT.createBlockBuilder(new BlockBuilderStatus(), length);
for (int i = start; i < start + length; i++) {
BIGINT.writeLong(blockBuilder, i);
}
return new Block[] {blockBuilder.build()};
}
@Override
public Number getExpectedValue(int start, int length)
{
if (length == 0) {
return null;
}
return 0L;
}
@Override
public Object getExpectedValueIncludingNulls(int start, int length, int lengthIncludingNulls)
{
return (long) lengthIncludingNulls - length;
}
@AggregationFunction("count_null")
public static final class CountNull
{
private CountNull() {}
@InputFunction
public static void input(@AggregationState NullableLongState state, @BlockPosition @NullablePosition @SqlType(StandardTypes.BIGINT) Block block, @BlockIndex int position)
{
if (block.isNull(position)) {
state.setLong(state.getLong() + 1);
}
state.setNull(false);
}
@CombineFunction
public static void combine(@AggregationState NullableLongState state, @AggregationState NullableLongState scratchState)
{
state.setLong(state.getLong() + scratchState.getLong());
state.setNull(state.isNull() && scratchState.isNull());
}
@OutputFunction(StandardTypes.BIGINT)
public static void output(@AggregationState NullableLongState state, BlockBuilder out)
{
NullableLongState.write(BIGINT, state, out);
}
}
@Override
protected String getFunctionName()
{
return "count_null";
}
@Override
protected List<String> getFunctionParameterTypes()
{
return ImmutableList.of(StandardTypes.BIGINT);
}
}