Thanks for the explanation, at least it's a start.
Bart
On Thu, Jun 22, 2017, at 11:20, Stefan Richter wrote:
> Hi,
>
> this „amazing error“ message typically means that the class of the object
> instance you created was loaded by a different classloader than the one
> that loaded the class in the code that tries to cast it. A class in Java
> is
> fully identified by the canonical classname AND the classloader that
> loaded it. This makes it possible that two classes with the same name and
> bytecode are not instance of each other. Unfortunately, I have no
> concrete idea why that happens in your case,
> but maybe this info helps to track down the problem.
>
> Best,
> Stefan
>
> > Am 22.06.2017 um 11:09 schrieb Bart van Deenen <bartvandee...@fastmail.fm>:
> >
> > Hi All
> >
> > I have a simple avro file
> >
> > {"namespace": "com.kpn.datalab.schemas.omnicrm.contact_history.v1",
> > "type": "record",
> > "name": "contactHistory",
> > "fields": [
> > {"name": "events", "type": {"type":"array",
> > "items": "bytes"}},
> > {"name": "krn", "type": "string"}
> > ]
> > }
> >
> > I generate a Java pojo (gist: https://goo.gl/FtM7T6) from this file via
> >
> > java -jar avro_tools.jar
> > Version 1.7.7 of Apache Avro
> >
> > java -jar bin/avro_tools.jar compile schema <avrofile>
> > generated/src/main/java
> >
> > This pojo file doesn't seem to want to be serialized by Flink, when I
> > pack the compiled class file into a fat-jar job file.
> >
> > When I pass a certain byte array into the avro deserializer, this works
> > fine in a regular Scala application, but when I do the same in a Flink
> > job it bombs with a typecast exception.
> >
> > Scala code:
> >
> > val payload: AnyRef = kafkaEvent.payload() // this calls the
> > Avro deserializer: (gist: https://goo.gl/18UqJy)
> >
> > println("canonical name: " + payload.getClass.getCanonicalName)
> > val chAvro =
> > try {
> > payload.asInstanceOf[contactHistory]
> > } catch {
> > case c:ClassCastException =>
> > println(c.getMessage)
> >
> > I get the following amazing error:
> >
> > "canonical name: " +
> > com.kpn.datalab.schemas.omnicrm.contact_history.v1.contactHistory
> > com.kpn.datalab.schemas.omnicrm.contact_history.v1.contactHistory cannot
> > be cast to
> > com.kpn.datalab.schemas.omnicrm.contact_history.v1.contactHistory
> >
> > I've verified the exact same code with the exact same byte-array input
> > (checked by printing a hexdump from the Flink job), and the code itself
> > is not the problem.
> >
> > If I put a jar containing the class file from the Pojo in the Flink lib
> > directory, my Flink job works fine!
> >
> > Any ideas how I can put my Pojo in the fat jar, because I don't want to
> > restart my Flink when I add new Avro schemas?
> >
> > Thanks
> >
> > Bart
>
