You don't have the Scala library on the app class path, which is used to implement Akka.
Use the same version that's required for the Akka libraries you're using. http://mvnrepository.com/artifact/org.scala-lang/scala-library dean Dean Wampler, Ph.D. Author: Programming Scala, 2nd Edition <http://shop.oreilly.com/product/0636920033073.do> (O'Reilly) Lightbend <http://lightbend.com> @deanwampler <http://twitter.com/deanwampler> http://polyglotprogramming.com On Wed, Jul 13, 2016 at 12:39 PM, Shekar Tippur <ctip...@gmail.com> wrote: > Dean, > > I am having trouble getting this to work. > > import akka.actor.ActorSystem; > import akka.kafka.scaladsl.Producer; > import akka.stream.javadsl.Source; > import akka.kafka.ProducerSettings; > import org.apache.kafka.clients.producer.ProducerRecord; > import org.apache.kafka.clients.producer.ProducerRecord; > import org.apache.kafka.common.serialization.ByteArrayDeserializer; > import org.apache.kafka.common.serialization.ByteArraySerializer; > import org.apache.kafka.common.serialization.StringDeserializer; > import org.apache.kafka.common.serialization.StringSerializer; > > abstract class KafkaPlProducer { > protected static ActorSystem system = ActorSystem.create("example"); > protected static ProducerSettings<byte[], String> producerSettings = > ProducerSettings.create(system, new ByteArraySerializer(), > new StringSerializer()) > .withBootstrapServers("localhost:9092"); > } > > class PlumberSink extends KafkaPlProducer { > //protected final ActorSystem system = ActorSystem.create("example"); > public static void main(String args[]) { > > Source.range(1, 10000) > .map(n -> n.toString()).map(elem -> new > ProducerRecord<byte[], String>("topic1", elem)) > .to(Producer.plainSink(producerSettings)); > } > //Source.range(1, 10000).map(n -> n.toString()).map(elem -> new > ProducerRecord<byte[], String>("topic1", > elem)).to(Producer.plainSink(producerSettings)); > > } > > > Here is the exception: > > Exception in thread "main" java.lang.NoClassDefFoundError: > scala/collection/Iterable > at > com.companyname.plumber.service.rest.api.internals.KafkaPlProducer.<clinit>(PlumberSink.java:25) > at java.lang.Class.forName0(Native Method) > at java.lang.Class.forName(Class.java:264) > at > com.intellij.rt.execution.application.AppMain.main(AppMain.java:122) > Caused by: java.lang.ClassNotFoundException: scala.collection.Iterable > at java.net.URLClassLoader.findClass(URLClassLoader.java:381) > at java.lang.ClassLoader.loadClass(ClassLoader.java:424) > at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) > at java.lang.ClassLoader.loadClass(ClassLoader.java:357) > ... 4 more > > > > On Sat, Jul 2, 2016 at 9:42 PM, Shekar Tippur <ctip...@gmail.com> wrote: > > > Dean, > > > > Thanks a lot for the link. I am going through the documentation. > > > > - Shekar > > > > On Wed, Jun 29, 2016 at 9:50 AM, Dean Wampler <deanwamp...@gmail.com> > > wrote: > > > >> Here's another Reactive API: https://github.com/akka/reactive-kafka > >> > >> It was developed by Software Mill <https://softwaremill.com/> and it's > >> now > >> being integrated with Akka <http://akka.io>. > >> > >> dean > >> > >> Dean Wampler, Ph.D. > >> Author: Programming Scala, 2nd Edition > >> <http://shop.oreilly.com/product/0636920033073.do> (O'Reilly) > >> Lightbend <http://lightbend.com> > >> @deanwampler <http://twitter.com/deanwampler> > >> http://polyglotprogramming.com > >> > >> On Wed, Jun 29, 2016 at 11:03 AM, Shekar Tippur <ctip...@gmail.com> > >> wrote: > >> > >> > Thanks for the suggestion Lohith. Will try that and provide a > feedback. > >> > > >> > - Shekar > >> > > >> > On Tue, Jun 28, 2016 at 11:45 PM, Lohith Samaga M < > >> > lohith.sam...@mphasis.com > >> > > wrote: > >> > > >> > > Hi Shekar, > >> > > Alternatively, you could make each stage of your pipeline to > >> > write > >> > > to a Cassandra (or other DB) and your API will read from it. With > >> > Cassandra > >> > > TTL, the row will be deleted after TTL is passed. No manual cleanup > is > >> > > required. > >> > > > >> > > Best regards / Mit freundlichen Grüßen / Sincères salutations > >> > > M. Lohith Samaga > >> > > > >> > > > >> > > > >> > > -----Original Message----- > >> > > From: Shekar Tippur [mailto:ctip...@gmail.com] > >> > > Sent: Wednesday, June 29, 2016 12.10 > >> > > To: users > >> > > Subject: Building API to make Kafka reactive > >> > > > >> > > I am looking at building a reactive api on top of Kafka. > >> > > This API produces event to Kafka topic. I want to add a unique > >> session id > >> > > into the payload. > >> > > The data gets transformed as it goes through different stages of a > >> > > pipeline. I want to specify a final topic where I want the api to > know > >> > that > >> > > the processing was successful. > >> > > The API should give different status at each part of the pipeline. > >> > > At the ingestion, the API responds with "submitted" > >> > > During the progression, the API returns "in progress" > >> > > After successful completion, the API returns "Success" > >> > > > >> > > Couple of questions: > >> > > 1. Is this feasible? > >> > > 2. I was looking at project reactor (https://projectreactor.io) > where > >> > the > >> > > docs talk about event bus. I wanted to see if I can implement a > >> consumer > >> > > that points to the "end" topic and throws an event into the event > bus. > >> > > Since I would know the session ID, I can process the request > >> accordingly. > >> > > > >> > > Appreciate your inputs. > >> > > > >> > > - Shekar > >> > > Information transmitted by this e-mail is proprietary to Mphasis, > its > >> > > associated companies and/ or its customers and is intended > >> > > for use only by the individual or entity to which it is addressed, > and > >> > may > >> > > contain information that is privileged, confidential or > >> > > exempt from disclosure under applicable law. If you are not the > >> intended > >> > > recipient or it appears that this mail has been forwarded > >> > > to you without proper authority, you are notified that any use or > >> > > dissemination of this information in any manner is strictly > >> > > prohibited. In such cases, please notify us immediately at > >> > > mailmas...@mphasis.com and delete this mail from your records. > >> > > > >> > > >> > > > > >
