Serialization in window contents and network buffers

[Alexis Sarda-Espinosa <sa...@gmail.com>]

Hi everyone,

I know the low level details of this are likely internal, but at a high
level we can say that operators usually have some state associated with
them. Particularly for error handling and job restarts, I imagine windows
must persist state, and operators in general probably persist network
buffers for anything that hasn't been processed or emitted.

Does Flink's serialization stack with type information applies to these
cases?

I ask specifically due to a use case I'm evaluating. I would have an
interface as output of some operators, and all those outputs would go into
a windowing operator. However, each non-windowing operator would emit a
different concrete class that implements the interface.

If I add @TypeInfo annotations to the concrete implementers, would Flink
find them and use them even if the operators are defined in terms of the
interface?

Regards,
Alexis.