What Is Grails

The Java framework built for consistency and simplicity

Grails is a high-productivity framework. Originally launched in 2005, Grails was known as Groovy on Rails, but in 2006 the name was changed after an issue with the founder of Ruby on Rails.

The goal of Grails was to provide a web framework for Java, pulling existing technologies like Hibernate and Spring into a single interface. This interface would offer a consistent workplace environment, as well as:

Documentation for the Persistent framework
Templates using Groovy Server Pages (GSP)
Dynamic tag libraries for creating web components
Customizable and extensible Ajax support

In the end, what the developers created was a powerful Groovy-based web application framework for the Java Virtual Machine built on top of Spring Boot.

There’s a bit to unpack there.

What are the components of Grails?

Let’s first examine the pieces that help make up Grails.

What is Apache Groovy?
Groovy is a multi-faceted, object-oriented programming language for Java, that was created by Apache. This language is optionally typed and dynamic, with static-typing and compilation capabilities. The goal of Groovy is to improve Java developer productivity by using concise, familiar, and easy-to-use syntax. Groovy seamless integrates with any Java program to provide them with:

Scripting capability
Domain-specific language
Authoring
Runtime- and compile-time meta-programming
Functional programming

Groovy can be used as both a programming and scripting language for Java and is compiled to Java Virtual Machine bytecode. Because of this, Groovy can interoperate with both Java code and libraries.

What is the Java Virtual Machine?
Simply put, the Java Virtual Machine (JVM) is a virtual machine that makes it possible for a computer to run Java programs and any other program that can be compiled into Java bytecode. Without the JVM, Java applications wouldn’t run.

What is Spring Boot?
Spring Boot is an open-source micro-framework that provides Java developers with a platform for creating auto-configurable, production-ready applications. Spring Boot is built on top of the Spring framework and includes several dependencies (such as Spring Kafka, Spring LDAP, Spring Web Service, and Spring Security) that can be inserted into your Spring application.

Spring Boot’s autoconfiguration feature makes it possible for developers to quickly change an app’s configuration based on a list of dependencies. For example, if MySQL is listed as a dependency, Spring Boot will automatically configure your Spring application with the MySQL connector.

Why use Grails over a traditional Java web application framework?

This is the heart of the matter. Your business probably already has Java developers, who are already adept at other frameworks. So why would you opt to add yet another framework into the mix? Three things cause Grails to stand out over traditional Java frameworks.

No need for XML configurations
When you create a web application in Java, you must configure both environment and frameworks before and during development. These XML configurations were designed to provide greater consistency for applications. However, recently it has become clear that configuring such apps through XML creates a tedious extra step to the process and reduces productivity.

Grails removes the need to configure apps through XML files. Instead, the framework uses a set of rules and conventions as it inspects the code of a Grails application.

Ready-to-use environment
When you develop with traditional Java web frameworks, you must assemble all of the pieces before you can begin. With Grails, you get a pre-constructed development environment that includes:

A webserver
All necessary libraries
Java web environment

With all of these pieces packed together out of the box, your engineers can start developing right away.

Support for Mixins
Grails includes support for dynamic methods for several classes through mixins, which is a class that includes methods that can be used by other classes without having to be a parent class to the other classes. Mixins allow developers to perform operations without having to first implement interfaces or extend base classes.

Other Grails features

Not only does Grails make it considerably easier for developers to get to work immediately, but it also includes a few other important features that help to make it stand out. Here is a shortlist of those features:

Seamless GORM integration - GORM is a data access toolkit that provides a set of APIs for accessing relational and non-relational data.
REST APIs - by using application profiles (such as React and Angular), Grails allows developers to build REST APIs and/or modern web apps using a JavaScript frontend.
Plugins - Developers can either make use of existing plugins or build their own to extend the functionality and features of the framework.
Support for View technology - Grails works with the likes of GSP, JSON Views, and Markup Views to effortlessly generate HTML, JSON, and XML.
Asynchronous - Grails includes support for async to simplify concurrent programming.
IDE support - Developers can program with Grails on IDEs such as IntelliJ IDEA, Eclipse, Sublime, and Textmate.

Conclusion

If you’re looking to empower your Java developers with a framework that can make their job easier and more efficient, consider Grails. With the ability to help your software engineers hit the ground running, you’ll find the software development lifecycle will be faster, which means you can deliver working applications to your clients sooner.