[ 
https://issues.apache.org/jira/browse/FLINK-3674?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15585562#comment-15585562
 ] 

ASF GitHub Bot commented on FLINK-3674:
---------------------------------------

Github user StefanRRichter commented on a diff in the pull request:

    https://github.com/apache/flink/pull/2570#discussion_r83858860
  
    --- Diff: 
flink-streaming-java/src/main/java/org/apache/flink/streaming/api/operators/InternalTimerService.java
 ---
    @@ -0,0 +1,60 @@
    +/*
    + * 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.streaming.api.operators;
    +
    +import org.apache.flink.annotation.Internal;
    +
    +/**
    + * Interface for working with time and timers.
    + *
    + * <p>This is the internal version of {@link 
org.apache.flink.streaming.api.TimerService}
    + * that allows to specify a key and a namespace to which timers should be 
scoped.
    + *
    + * @param <N> Type of the namespace to which timers are scoped.
    + */
    +@Internal
    +public interface InternalTimerService<N> {
    +
    +   /** Returns the current processing time. */
    +   long currentProcessingTime();
    +
    +   /** Returns the current event time. */
    +   long currentWatermark();
    --- End diff --
    
    The corresponding method in the public interface is called 
`currentEventTime`. Does it makes sense to keep both method names synchronous? 


> Add an interface for Time aware User Functions
> ----------------------------------------------
>
>                 Key: FLINK-3674
>                 URL: https://issues.apache.org/jira/browse/FLINK-3674
>             Project: Flink
>          Issue Type: New Feature
>          Components: Streaming
>    Affects Versions: 1.0.0
>            Reporter: Stephan Ewen
>            Assignee: Aljoscha Krettek
>
> I suggest to add an interface that UDFs can implement, which will let them be 
> notified upon watermark updates.
> Example usage:
> {code}
> public interface EventTimeFunction {
>     void onWatermark(Watermark watermark);
> }
> public class MyMapper implements MapFunction<String, String>, 
> EventTimeFunction {
>     private long currentEventTime = Long.MIN_VALUE;
>     public String map(String value) {
>         return value + " @ " + currentEventTime;
>     }
>     public void onWatermark(Watermark watermark) {
>         currentEventTime = watermark.getTimestamp();
>     }
> }
> {code}



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to