package com.facebook.presto.operator.scalar;
/*
* 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.
*/
import com.facebook.presto.annotation.UsedByGeneratedCode;
import com.facebook.presto.metadata.BoundVariables;
import com.facebook.presto.metadata.FunctionRegistry;
import com.facebook.presto.metadata.SqlOperator;
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.google.common.collect.ImmutableList;
import java.lang.invoke.MethodHandle;
import static com.facebook.presto.metadata.Signature.comparableWithVariadicBound;
import static com.facebook.presto.spi.function.OperatorType.HASH_CODE;
import static com.facebook.presto.spi.type.TypeSignature.parseTypeSignature;
import static com.facebook.presto.util.Reflection.methodHandle;
public class RowHashCodeOperator
extends SqlOperator
{
public static final RowHashCodeOperator ROW_HASH_CODE = new RowHashCodeOperator();
private static final MethodHandle METHOD_HANDLE = methodHandle(RowHashCodeOperator.class, "hash", Type.class, Block.class);
private RowHashCodeOperator()
{
super(HASH_CODE,
ImmutableList.of(comparableWithVariadicBound("T", "row")),
ImmutableList.of(),
parseTypeSignature(StandardTypes.BIGINT),
ImmutableList.of(parseTypeSignature("T")));
}
@Override
public ScalarFunctionImplementation specialize(BoundVariables boundVariables, int arity, TypeManager typeManager, FunctionRegistry functionRegistry)
{
Type type = boundVariables.getTypeVariable("T");
return new ScalarFunctionImplementation(false, ImmutableList.of(false), METHOD_HANDLE.bindTo(type), isDeterministic());
}
@UsedByGeneratedCode
public static long hash(Type rowType, Block block)
{
BlockBuilder blockBuilder = rowType.createBlockBuilder(new BlockBuilderStatus(), 1);
blockBuilder.writeObject(block).closeEntry();
return rowType.hash(blockBuilder.build(), 0);
}
}