| /* |
| * 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.flink.table.functions |
| |
| import org.apache.flink.api.common.typeinfo.TypeInformation |
| import org.apache.flink.table.expressions.{AggFunctionCall, DistinctAgg, Expression} |
| import org.apache.flink.table.functions.utils.UserDefinedFunctionUtils.{getAccumulatorTypeOfAggregateFunction, getResultTypeOfAggregateFunction} |
| |
| /** |
| * Defines an implicit conversion method (distinct) that converts [[AggregateFunction]]s into |
| * [[DistinctAgg]] Expressions. |
| */ |
| private[flink] case class DistinctAggregateFunction[T: TypeInformation, ACC: TypeInformation] |
| (aggFunction: AggregateFunction[T, ACC]) { |
| |
| def distinct(params: Expression*): Expression = { |
| val resultTypeInfo: TypeInformation[_] = getResultTypeOfAggregateFunction( |
| aggFunction, |
| implicitly[TypeInformation[T]]) |
| |
| val accTypeInfo: TypeInformation[_] = getAccumulatorTypeOfAggregateFunction( |
| aggFunction, |
| implicitly[TypeInformation[ACC]]) |
| |
| DistinctAgg( |
| AggFunctionCall(aggFunction, resultTypeInfo, accTypeInfo, params)) |
| } |
| } |
