OpenXava - OpenXava is a Web Java Framework for Rapid Development of Enterprise Applications.
Grails - An Open Source, full stack, web application framework for the JVM
Apache Sling - Apache Sling is a REST based web framework,
Vaadin Framework - Vaadin is a web application framework for Rich Internet Applications (RIA).
Spring Framework - The Spring Framework provides a comprehensive programming and configuration model for modern Java-based enterprise applications - on any kind of deployment platform.
REI3 - Fulfill your software requirements with REI3 on-premise or in the cloud. REI3 is an open platform for pre- or self-built web applications.