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From Fabian Hueske <fhue...@gmail.com>
Subject Re: When does Trigger.clear() get called?
Date Mon, 15 Oct 2018 07:36:54 GMT
Hi,

Re Q1: The main purpose of the Trigger.clean() method is to remove all
custom state of the Trigger. State must be explicitly removed, otherwise
the program leaks memory.
Re Q3: If you are using a keyed stream, you need to manually clean up the
state by calling State.clear(). If you are using a ProcessFunction, you can
do that in processElement() or register a timer and clean up in onTimer().

Best, Fabian

Am So., 14. Okt. 2018 um 06:06 Uhr schrieb Averell <lvhuyen@gmail.com>:

> Hello Hequn,
>
> Thanks for the answers.
> Regarding question no.2, I am now clear.
> Regarding question no.1, does your answer apply to those custom states as
> well? This concern of mine came from Flink's implementation of
> CountTrigger,
> in which a custom state is being cleared explicitly in Trigger.clear():
>
> /       public void clear(W window, TriggerContext ctx) throws Exception {
>                 ctx.getPartitionedState(stateDesc).clear();
>         }
> /
>
> My 3rd question was for ordinary, non-windowed keyed streams, where I don't
> see in Flink's document any mention of using Trigger, so how can I clear
> those streams?
>
> Thank you very much for your help.
> Regards,
> Averell
>
>
>
>
> --
> Sent from:
> http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/
>

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