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ASF GitHub Bot commented on FLINK-4693: --------------------------------------- Github user twalthr commented on a diff in the pull request: https://github.com/apache/flink/pull/3150#discussion_r96605812 --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/table/runtime/aggregate/DataSetSessionWindowAggregateCombineGroupFunction.scala --- @@ -0,0 +1,133 @@ +/* + * 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.runtime.aggregate + +import java.lang.Iterable + +import org.apache.flink.api.common.functions.RichGroupCombineFunction +import org.apache.flink.api.common.typeinfo.TypeInformation +import org.apache.flink.api.java.typeutils.ResultTypeQueryable +import org.apache.flink.types.Row +import org.apache.flink.configuration.Configuration +import org.apache.flink.util.{Collector, Preconditions} + +import scala.collection.JavaConversions._ + +/** + * This wraps the aggregate logic inside of + * [[org.apache.flink.api.java.operators.GroupCombineOperator]]. + * + * @param aggregates The aggregate functions. + * @param groupingKeys + * @param intermediateRowArity The intermediate row field count. + * @param gap Session time window gap. + * @param intermediateRowType Intermediate row data type. + */ +class DataSetSessionWindowAggregateCombineGroupFunction( + aggregates: Array[Aggregate[_ <: Any]], + groupingKeys: Array[Int], + intermediateRowArity: Int, + gap: Long, + @transient intermediateRowType: TypeInformation[Row]) + extends RichGroupCombineFunction[Row,Row] with ResultTypeQueryable[Row] { + + private var aggregateBuffer: Row = _ + private var rowTimePos = 0 + + override def open(config: Configuration) { + Preconditions.checkNotNull(aggregates) + Preconditions.checkNotNull(groupingKeys) + aggregateBuffer = new Row(intermediateRowArity) + rowTimePos = intermediateRowArity - 2 + } + + /** + * For sub-grouped intermediate aggregate Rows, divide window based on the row-time + * (current'row-time - previous’row-time > gap), and then merge data (within a unified window) + * into an aggregate buffer. + * + * @param records Sub-grouped intermediate aggregate Rows . + * @return Combined intermediate aggregate Row. + * + */ + override def combine( + records: Iterable[Row], + out: Collector[Row]): Unit = { + + var head:Row = null + var lastRowTime: Option[Long] = None + var currentRowTime: Option[Long] = None + + records.foreach( --- End diff -- We should avoid Scala magic in runtime classes as much as possible. Because we don't know the runtime behavior. Can you replace this by a while loop? > Add session group-windows for batch tables > ------------------------------------------- > > Key: FLINK-4693 > URL: https://issues.apache.org/jira/browse/FLINK-4693 > Project: Flink > Issue Type: Sub-task > Components: Table API & SQL > Reporter: Timo Walther > Assignee: sunjincheng > > Add Session group-windows for batch tables as described in > [FLIP-11|https://cwiki.apache.org/confluence/display/FLINK/FLIP-11%3A+Table+API+Stream+Aggregations]. > -- This message was sent by Atlassian JIRA (v6.3.4#6332)