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.metadata.FunctionRegistry;
import com.facebook.presto.metadata.Signature;
import com.facebook.presto.metadata.SqlOperator;
import com.facebook.presto.spi.PrestoException;
import com.facebook.presto.spi.block.Block;
import com.facebook.presto.spi.function.OperatorType;
import com.facebook.presto.spi.type.StandardTypes;
import com.facebook.presto.spi.type.Type;
import com.facebook.presto.type.RowType;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableList;
import java.lang.invoke.MethodHandle;
import java.util.List;
import static com.facebook.presto.metadata.Signature.orderableWithVariadicBound;
import static com.facebook.presto.spi.StandardErrorCode.GENERIC_INTERNAL_ERROR;
import static com.facebook.presto.spi.type.TypeSignature.parseTypeSignature;
import static com.facebook.presto.spi.type.TypeUtils.readNativeValue;
import static com.facebook.presto.type.TypeUtils.checkElementNotNull;
public abstract class RowComparisonOperator
extends SqlOperator
{
protected RowComparisonOperator(OperatorType operatorType)
{
super(operatorType,
ImmutableList.of(orderableWithVariadicBound("T", StandardTypes.ROW)),
ImmutableList.of(),
parseTypeSignature(StandardTypes.BOOLEAN),
ImmutableList.of(parseTypeSignature("T"), parseTypeSignature("T")));
}
protected List<MethodHandle> getMethodHandles(RowType type, FunctionRegistry functionRegistry, OperatorType operatorType)
{
ImmutableList.Builder<MethodHandle> argumentMethods = ImmutableList.builder();
for (Type parameterType : type.getTypeParameters()) {
Signature signature = functionRegistry.resolveOperator(operatorType, ImmutableList.of(parameterType, parameterType));
argumentMethods.add(functionRegistry.getScalarFunctionImplementation(signature).getMethodHandle());
}
return argumentMethods.build();
}
protected static int compare(
RowType rowType,
List<MethodHandle> comparisonFunctions,
Block leftRow,
Block rightRow)
{
for (int i = 0; i < leftRow.getPositionCount(); i++) {
checkElementNotNull(leftRow.isNull(i), "null value at position " + i);
checkElementNotNull(rightRow.isNull(i), "null value at position " + i);
Type type = rowType.getTypeParameters().get(i);
Object leftElement = readNativeValue(type, leftRow, i);
Object rightElement = readNativeValue(type, rightRow, i);
try {
if ((boolean) comparisonFunctions.get(i).invoke(leftElement, rightElement)) {
return 1;
}
if ((boolean) comparisonFunctions.get(i).invoke(rightElement, leftElement)) {
return -1;
}
}
catch (Throwable t) {
Throwables.propagateIfInstanceOf(t, Error.class);
Throwables.propagateIfInstanceOf(t, PrestoException.class);
throw new PrestoException(GENERIC_INTERNAL_ERROR, t);
}
}
return 0;
}
}