Hi Dominik,
Flink does not use Java serialization logic for network communication.
So objects must not implement `Serializable` for usage during runtime
(DataStream<Data>).
Only if those classes are member variables of a Function like
MapFunction, they need to serializable to ship the function code to the
cluster.
You can check which serializer and nested serializers are used by calling:
dataStream.getType().createTypeSerializer(env.getExecutionConfig)
Regards,
Timo
On 14.04.20 12:55, Dominik Wosiński wrote:
Hey,
I have a question about using classes with fields that are not
serializable in DataStream. Basically, I would like to use the Java's
Optional in DataStream. So Say I have a class /Data /that has several
optional fields and I would like to have /DataStream<Data>/. I don't
think this should cause any issues, but I thought it can be good to ask
whether this can cause any issues with Flink Jobs.
Thanks,
Best,
Dom.
