Grails is an open source web application framework that uses the Apache Groovy programming language. It is intended to be a high-productivity framework by following the "coding by convention" paradigm, providing a stand-alone development environment and hiding much of the configuration detail from the developer.
Spring Framework provides a comprehensive programming and configuration model for modern Java-based enterprise applications - on any kind of deployment platform.
J2EE (by Oracle) is a platform-independent, Java-centric environment from Sun for developing, building and deploying Web-based enterprise applications online