Hi Dominik,
Flink does not use Java serialization logic for network communication.
So objects must not implement `Serializable` for usage during runtime
(DataStream).
Only if those classes are member variables of a Function like
MapFunction, they need to serializable to ship the function
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*. I don't think this should
cause
