| /** |
| * 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.tajo.engine.function; |
| |
| import org.apache.tajo.catalog.Column; |
| import org.apache.tajo.catalog.json.CatalogGsonHelper; |
| import org.apache.tajo.catalog.proto.CatalogProtos; |
| import org.apache.tajo.common.TajoDataTypes.DataType; |
| import org.apache.tajo.datum.Datum; |
| import org.apache.tajo.exception.InvalidOperationException; |
| import org.apache.tajo.storage.Tuple; |
| |
| public abstract class WindowAggFunc<T extends Datum> extends AggFunction<T> { |
| |
| public WindowAggFunc(Column[] definedArgs) { |
| super(definedArgs); |
| } |
| |
| public abstract FunctionContext newContext(); |
| |
| public abstract void eval(FunctionContext ctx, Tuple params); |
| |
| public void merge(FunctionContext ctx, Tuple part) { |
| throw new InvalidOperationException("Window function does not support getPartialResult()"); |
| } |
| |
| public Datum getPartialResult(FunctionContext ctx) { |
| throw new InvalidOperationException("Window function does not support getPartialResult()"); |
| } |
| |
| public DataType getPartialResultType() { |
| throw new InvalidOperationException("Window function does not support getPartialResultType()"); |
| } |
| |
| public abstract T terminate(FunctionContext ctx); |
| |
| @Override |
| public String toJson() { |
| return CatalogGsonHelper.toJson(this, WindowAggFunc.class); |
| } |
| |
| @Override |
| public CatalogProtos.FunctionType getFunctionType() { |
| return CatalogProtos.FunctionType.WINDOW; |
| } |
| } |