Your entity is serializable and you want to send it from server to client. Most JPA providers enhance entity classes to support features like lazy loading, so although you have used a java.util.List in your entity code it could very well become an org.apache.openjpa.kernel.DelegatingResultList after the class has been enhanced by your JPA provider. You should check this in the OpenJPA documentation.
If this class does not implement serializable or is not visible to the GWT compiler it does not end up in your serialization policy file (thats the <hash>.rpc file). The server checks against this file during serialization and gives you the above error. A common way to solve this is to use DTO classes. GWT's RequestFactory for example does something similar by using Autobeans on the client side and let the server classes be pure server classes. -- J. -- You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. To view this discussion on the web visit https://groups.google.com/d/msg/google-web-toolkit/-/Kg2zCUgCXXQJ. To post to this group, send email to google-web-toolkit@googlegroups.com. To unsubscribe from this group, send email to google-web-toolkit+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-web-toolkit?hl=en.
