GWTApp provides several features like: HTML templating and messaging at runtime without application recompiling, MetaField to auto bind and simulate annotation of RPC data fields, Strong typing in MVC, Modular structure in Maven.
jPersist is an object-relational persistence API with automatic mapping, and based on the ActiveRecord and DataMapper patterns. jWebApp is an MVC web application framework. Both are configuration and annotation free and can be learned in minutes