jHipster - JHipster is a development platform to quickly generate, develop, & deploy modern web applications & microservice architectures.
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.
Open As App - Automatically create a business app from a spreadsheet, no coding.
Grails - An Open Source, full stack, web application framework for the JVM
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.