Hi Sandeep,
did you have a chance to look at this documentation page?
https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/state/custom_serialization.html
The interfaces might not be easy to implement but are very powerful to
address compatibility issues. You can also look into Flink serializers
for some examples:
https://github.com/apache/flink/tree/master/flink-core/src/main/java/org/apache/flink/api/java/typeutils/runtime
Esp:
https://github.com/apache/flink/blob/89c6c03660a88a648bbd13b4e6696124fe46d013/flink-core/src/main/java/org/apache/flink/api/java/typeutils/runtime/PojoSerializer.java#L599
For the POJO logic.
By the way, usually we recommend Avro for state data structures if
schema evolution is a topic.
Regards,
Timo
On 29.04.21 18:10, Sandeep khanzode wrote:
Hello,
Is there a working example of a TypeSerializer for a Java type stored in
the State?
My requirement is that I should be able to store the Java POJO entity in
the MapState. The state is backed by RocksDBBackend.
If I update the entity with a new member variable, I am unable to
deserialise the state into the new entity.
I checked this link.
https://ci.apache.org/projects/flink/flink-docs-release-1.12/dev/types_serialization.html
<https://ci.apache.org/projects/flink/flink-docs-release-1.12/dev/types_serialization.html>
It does mention that the POJO type is special based on the rules. Does
that mean that I can add or remove member variables for the POJO? I have
been unable to get it to work.
Thanks,
Sandeep
