As far as I understand the idea of JSON, it's supposed to be cross-language, and hence doesn't really have a concept of "classes". At least JSON does not want to serialize blessed objects by default, and I guess that there is no way to (de)serialize whole class trees. Maybe you can store the class name as a separate field for each object and upon deserialization rebless all elements?

Thanks for reply. I agree with your suggestion

Storable and Data::Dumper and others just produce string data, and can serialize perl objects. If all you care about is something that's technically JSON and you only pass it to other perl code, you can put the serialized string into a JSON attribute and retrieve it on the other side.

The real question would then be: why use JSON at all?