I have a relatively simple entity model that I’m attempting to use Vaadin CRUD for in order to speed up development. I have found that the default create action works fine but any attempt to edit an entity fails with the exception stack trace attached. The exception causes any further attempt to use the CRUD editor to fail. It always seems as though the framework is attempting to locate a grid entity with a key = max key in GRID + 1 after the edit event has been fired and the attempt to persist the entity update is actioned.
Editing is working fine for me, you should maybe add more information about your entity model, and how your crud is set up.