[ https://issues.apache.org/jira/browse/FLINK-7245?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16131401#comment-16131401 ]
ASF GitHub Bot commented on FLINK-7245: --------------------------------------- Github user fhueske commented on a diff in the pull request: https://github.com/apache/flink/pull/4530#discussion_r133842744 --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/table/runtime/operators/KeyedCoProcessOperatorWithWatermarkDelay.scala --- @@ -0,0 +1,45 @@ +/* + * 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.operators + +import org.apache.flink.streaming.api.functions.co.CoProcessFunction +import org.apache.flink.streaming.api.operators.co.KeyedCoProcessOperator +import org.apache.flink.streaming.api.watermark.Watermark + +/** + * A {@link org.apache.flink.streaming.api.operators.co.KeyedCoProcessOperator} that supports + * holding back watermarks with a static delays. + */ +class KeyedCoProcessOperatorWithWatermarkDelay[KEY, IN1, IN2, OUT]( + private val flatMapper: CoProcessFunction[IN1, IN2, OUT], + private val watermarkDelay1: Long = 0L, + // The watermarkDelay2 is useless now + private var watermarkDelay2: Long = 0L) --- End diff -- Since this is an internal class, we don't need to be concerned about changing the interface later. I'd suggest to remove `watermarkDelay2` and add it later when we need it. > Enhance the operators to support holding back watermarks > -------------------------------------------------------- > > Key: FLINK-7245 > URL: https://issues.apache.org/jira/browse/FLINK-7245 > Project: Flink > Issue Type: New Feature > Components: DataStream API > Reporter: Xingcan Cui > Assignee: Xingcan Cui > > Currently the watermarks are applied and emitted by the > {{AbstractStreamOperator}} instantly. > {code:java} > public void processWatermark(Watermark mark) throws Exception { > if (timeServiceManager != null) { > timeServiceManager.advanceWatermark(mark); > } > output.emitWatermark(mark); > } > {code} > Some calculation results (with timestamp fields) triggered by these > watermarks (e.g., join or aggregate results) may be regarded as delayed by > the downstream operators since their timestamps must be less than or equal to > the corresponding triggers. > This issue aims to add another "working mode", which supports holding back > watermarks, to current operators. These watermarks should be blocked and > stored by the operators until all the corresponding new generated results are > emitted. -- This message was sent by Atlassian JIRA (v6.4.14#64029)