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Aljoscha Krettek commented on FLINK-3674: ----------------------------------------- Correct, we could also have {{onProcessingTimeTimer()}} and {{onEventTimeTImer()}} but then users would always have to implement both. In most cases, I imagine, users would only set one type of timer and don't care about differentiation in the {{onTimer}} method because they know that they will only get one type. > 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)