FrontendSource - Curated dev & designer resources updated weekly
OpenXava - OpenXava is a Web Java Framework for Rapid Development of Enterprise Applications.
Material Up - Curates the best of Material Design inspiration, tools and freebies.
jHipster - JHipster is a development platform to quickly generate, develop, & deploy modern web applications & microservice architectures.
Atomic - The fastest way to design beautiful interactions
Spring Framework - The Spring Framework provides a comprehensive programming and configuration model for modern Java-based enterprise applications - on any kind of deployment platform.