Groovy & Grails Quick Start

A Friendly Language for the JVM Groovy is a language that runs on the JVM but cuts away much of the ceremony of Java. Semicolons are optional, getters and setters are generated ...

What You Need Both Groovy and Grails run on the Java Virtual Machine, so the JDK comes first. Use a recent Long Term Support release like JDK 17 or 21. After the JDK is installed, ...

Groovy Syntax in a Nutshell Groovy looks familiar to Java developers but with deliberate shortcuts. The def keyword declares a dynamically typed variable. Statements can end with ...

What Is a Closure A closure is a block of code wrapped in curly braces that you can store in a variable and pass around. Closures capture the surrounding variables, so they behave ...

The Create and Run Cycle Grails has a command line tool that scaffolds a whole application. From an empty folder you create a project, then start a development server. The first ...

Domain Classes Model Your Data A domain class describes a table in your database. The class name becomes the table name, each property becomes a column, and each instance becomes ...

Controllers Receive HTTP A controller delivers HTTP requests to the right code and returns a response. Each public method on a controller is an action, and Grails maps a URL to an ...

GSP Is HTML with Groovy GSP, Groovy Server Pages, is the Grails view technology. Files live under grails-app/views and mirror the controller and action names. A GSP file is mostly ...

Services Hold Business Logic Services are Grails classes that live in grails-app/services. They hold the business rules that should not sit inside controllers or domain classes. ...

Testing Is Built In Grails generates a test for every domain class, controller, and service you create. You can write unit tests that run fast without a database, integration ...