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From Alexander T <>
Subject Re: initState method not invoked in Storm 1.0
Date Fri, 15 Apr 2016 09:08:45 GMT
Hi Arun,

I meant that it's very easy to use the wrong setBolt method overload by
mistake, since stateful bolts are supertypes of stateless ones.

On Apr 15, 2016 10:54 AM, "Arun Mahadevan" <> wrote:

Its the same method (builder.setBolt) that adds stateful bolts to a
topology. Heres an example -


Do you see any errors in the logs ? You might want to turn on debug logs
and see whats happening. Can you also try running the StatefulTopology in
the storm-starter and check if you see the same behavior ?


From: Alexander T
Reply-To: ""
Date: Friday, April 15, 2016 at 2:06 PM
To: ""
Subject: Re: initState method not invoked in Storm 1.0

Hi Spico,

Are you adding your bolt to the topology with the special methods for
stateful bolts? It's quite easy to use the regular addBolt method and it
will in that case be treated as a stateless one.

On Apr 15, 2016 10:33 AM, "Spico Florin" <> wrote:

> Hello!
>   I'm running a topology in LocalCluster that has a stasteful Bolt. Wile
> debugging, I have observed that the initState method is not invoked at all.
> The documentation said:
> "The initState method is invoked by the framework during the bolt
> initialization with the previously saved state of the bolt. This is invoked
> after prepare but before the bolt starts processing any tuples".
> Due to this, the state field remains null and I get NPE when I populate it
> with state .put
> Any idea why the initState is not invoked?
> Regards,
>  Florin
> Here is my code:
> public class TimeSeriesStatefulBolt extends
> BaseStatefulBolt<KeyValueState<Long, Map<String, Float>>> {
> private KeyValueState<Long, Map<String, Float>> state;
> @Override
> public void initState(KeyValueState<Long, Map<String, Float>> state) {
> this.state = state;
> }

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