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From Debasish Ghosh <ghosh.debas...@gmail.com>
Subject Re: SAM Scala aggregate
Date Sun, 09 Sep 2018 17:13:33 GMT
Which version of Scala are u using ?

On Sun, 9 Sep 2018 at 10:44 AM, Michael Eugene <fartzy@hotmail.com> wrote:

> Hi,
>
>   I am using kafak-sreams-scala
> https://github.com/lightbend/kafka-streams-scala, and I am trying to
> implement something very simple and I am getting a compilation error by the
> "aggregate" method. The error is "Cannot resolve overload method
> 'aggregate'" and "Unspecified value parameters: materialized:
> Materialized[String, NotInferedVR, KeyValueStore[Bytes, Array[Byte]]]"
> [https://avatars0.githubusercontent.com/u/16247783?s=400&v=4]<
> https://github.com/lightbend/kafka-streams-scala>
>
> GitHub
>  - lightbend/kafka-streams-scala: Thin Scala wrapper ...<
> https://github.com/lightbend/kafka-streams-scala>
> github.com
> Note:
>  Scala API for Kafka Streams have been accepted for inclusion in Apache
> Kafka. We have been working with the Kafka team since the last couple of
> months working towards meeting the standards and guidelines for this
> activity. Lightbend and Alexis Seigneurin have
>  contributed this library (with ...
>
>
>
>   However when I add a third argument for a Materialized, I get the
> compilation error "Too may arguments for method aggregate(() =>VR, (K,V,VR)
> => VR)"
>
>   It doesn't make sense anymore what could be breaking this.
>
>
>
> val myStream = builder
>   .stream(inputTopic)
>   .map{ (key: String, value: Array[Byte]) =>
>     println(s"key = ${key}")
>     val newKey = GroupByAction.getGroupByKeyFromByteAray(value)
>
>     val newValue = GroupByAction.getGroupByValueFromByteAray(value)
>
>     println(s"newKey = ${newKey}")
>     (newKey, serialise(newValue))}
>
> .groupByKey
> .aggregate(()=> 0L, (k,v,vr) => vr + 1)
>
> --
Sent from my iPhone

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