/*
* Licensed to CRATE Technology GmbH ("Crate") under one or more contributor
* license agreements. See the NOTICE file distributed with this work for
* additional information regarding copyright ownership. Crate licenses
* this file to you 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.
*
* However, if you have executed another commercial license agreement
* with Crate these terms will supersede the license and you may use the
* software solely pursuant to the terms of the relevant commercial agreement.
*/
package io.crate.operation.scalar.arithmetic;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import io.crate.metadata.*;
import io.crate.operation.Input;
import io.crate.operation.scalar.ScalarFunctionModule;
import io.crate.planner.symbol.Function;
import io.crate.planner.symbol.Literal;
import io.crate.planner.symbol.Symbol;
import io.crate.types.DataType;
import io.crate.types.DataTypes;
import java.util.List;
import java.util.Set;
public class AbsFunction extends Scalar<Number, Number> {
public static final String NAME = "abs";
private static final Set<DataType> ALLOWED_TYPES = ImmutableSet.<DataType>builder()
.addAll(DataTypes.NUMERIC_PRIMITIVE_TYPES)
.add(DataTypes.UNDEFINED)
.build();
public static void register(ScalarFunctionModule module) {
module.register(NAME, new Resolver());
}
private final FunctionInfo info;
public AbsFunction(DataType dataType) {
this.info = new FunctionInfo(
new FunctionIdent(NAME, ImmutableList.of(dataType)), dataType);
}
@Override
public FunctionInfo info() {
return info;
}
@Override
public Symbol normalizeSymbol(Function symbol) {
Symbol argument = symbol.arguments().get(0);
if (argument.symbolType().isValueSymbol()) {
return Literal.newLiteral(info().returnType(), evaluate((Input) argument));
}
return symbol;
}
@Override
public Number evaluate(Input<Number>... args) {
assert args.length == 1;
Number value = args[0].value();
if (value != null) {
return (Number)info.returnType().value(Math.abs(value.doubleValue()));
}
return null;
}
private static class Resolver implements DynamicFunctionResolver {
@Override
public FunctionImplementation<Function> getForTypes(List<DataType> dataTypes) throws IllegalArgumentException {
Preconditions.checkArgument(dataTypes.size() == 1,
"invalid size of arguments, 1 expected");
Preconditions.checkArgument(ALLOWED_TYPES.contains(dataTypes.get(0)),
"invalid datatype %s for %s function", dataTypes.get(0).toString(), NAME);
return new AbsFunction(dataTypes.get(0));
}
}
}