If you are considering Grails, you may also want to investigate similar alternatives or competitors to find the best solution. Other important factors to consider when researching alternatives to Grails include plugins. The best overall Grails alternative is spring.io. Other similar apps like Grails are Spark, Vraptor, JHipster, and Play. Grails alternatives can be found in Java Web Frameworks but may also be in JavaScript Web Frameworks.
Spark - A micro framework for creating web applications in Java 8 with minimal effort
VRaptor 4 delivers high productivity to your Java Web applications on top of CDI. VRaptor is an opensource MVC framework with a large developers and users community.
The High Velocity Web Framework For Java and Scala
Apache Struts is a free, open-source, MVC framework for creating elegant, modern Java web applications. It favors convention over configuration, is extensible using a plugin architecture, and ships with plugins to support REST, AJAX and JSON.
Build your web UIs in HTML or Java
The Apache Software Foundation announces Apache Wicket v7.0 Open Source Java web framework that powers thousands of web applications and web sites for governments, stores, universities, cities, banks, email providers, and more.
Jmix is a high level framework for the rapid development of enterprise applications with rich web interfaces. The platform abstracts developers from underlying technologies so they can focus on the business tasks, whilst retaining full flexibility by providing unrestricted access to low level code.
RAP provides a powerful widget toolkit and integrates well with proven technologies such as OSGi and JEE. You can write your application entirely in Java, re-use code and benefit from first-class IDE tools.