| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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. |
| */ |
| package org.apache.drill.exec.expr.fn; |
| |
| import org.apache.drill.common.expression.LogicalExpression; |
| import org.apache.drill.common.types.TypeProtos; |
| import org.apache.drill.exec.expr.annotations.FunctionTemplate; |
| |
| import java.util.List; |
| |
| public class FunctionUtils { |
| |
| /** |
| * Calculates return type data mode based on give logical expressions. |
| * If null handling strategy is internal, returns return value data mode. |
| * If null handling strategy is null if null and at least one of the input types are nullable, |
| * return nullable data mode. |
| * |
| * @param logicalExpressions logical expressions |
| * @param attributes function attributes |
| * @return data mode |
| */ |
| public static TypeProtos.DataMode getReturnTypeDataMode(final List<LogicalExpression> logicalExpressions, FunctionAttributes attributes) { |
| if (attributes.getNullHandling() == FunctionTemplate.NullHandling.NULL_IF_NULL) { |
| for (final LogicalExpression logicalExpression : logicalExpressions) { |
| if (logicalExpression.getMajorType().getMode() == TypeProtos.DataMode.OPTIONAL) { |
| return TypeProtos.DataMode.OPTIONAL; |
| } |
| } |
| } |
| return attributes.getReturnValue().getType().getMode(); |
| } |
| |
| } |