This is a great question, and explains why we decided that the durable storage API needed to be explicit, rather than automatically serializing the in-memory object. Nothing is stored unless you explicitly use storage.put(key, value).
Since the storage is explicit, it's easy to upgrade the class definition. The in-memory object will be reconstructed and will need to refresh its state from storage.
Since the storage is explicit, it's easy to upgrade the class definition. The in-memory object will be reconstructed and will need to refresh its state from storage.