[FLINK-3674] Add an interface for Time aware User Functions

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0
• Fix Version/s: 1.2.0
• Component/s: API / DataStream
• Assignee: Aljoscha Krettek
• Reporter: Stephan Ewen
• Created: 29/Mar/16 10:11
• Updated: 28/Feb/19 11:14
• Resolved: 21/Oct/16 17:17

Description

I suggest to add an interface that UDFs can implement, which will let them be notified upon watermark updates.

Example usage:

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();
    }
}

Issue Links

• links to: GitHub Pull Request #2301
• links to: GitHub Pull Request #2570

Sub-Tasks

• Refactorings around FLINK-3674 (User Function Timers): Resolved