Setting up your Eclipse environment for Groovy and Grails

13 January 2011 // Christian Hilmersson

This article covers how to setup your standard Eclipse environment with plugins from SpringSource for developing Groovy and Grails applications without using the full SpringSource Tool Suite.

Background

It is more and more common that we see other languages than Java running on the JVM. One such language is Groovy which together with the Ruby on Rails inspired framework Grails forms a good platform for rapid development of simple web applications.

SpringSource Tool Suite is an extended Eclipse with support for a lot of interesting things. There’s is good support for developing Groovy and Grails applications in the SpringSource Tool Suite IDE, easy to setup via the built-in extension mechanism which is available in the Extensions tab on the STS Dashboard.

If however, we are interested in developing Groovy and Grails applications and don’t care so much about all the other stuff that SpringSource Tool Suite is packaging it is possible to pick out only the plug-ins that we need from the SpringSource Tool Suite and apply them to a clean Eclipse version.

This article presents a way of setting up a development environment for Groovy and Grails inside Eclipse.

Download Java Development Kit

Some of the functionalities in the Grails framework requires you to have a JDK installed.

Make sure that you have a JDK of version J2SE 1.6 installed and that your JAVA_HOME environment variable points to the JDK and that Eclipse uses it on the build path of your projects, otherwise follow the instructions below.

• Go to the JDK Download page at Oracle and download Java SE Development Kit 6u23.
• Follow the instructions in the installer to install the JDK on your computer.
• Make sure that the JAVA_HOME environment variable exists and points at your installed JDK JAVA_HOME="c:\Program Files\Java\jdk1.6.0_23"
• Start Eclipse and open Preferences/Java/Installed JREs
• Click Add…, Choose Standard VM and click Next.
• Click Directory and choose the home folder of your JDK (e.g. c:\Program Files\Java\jdk1.6.0_23)
• Click Finish to get back to the preferences.
• Use the checkbox next to the JDK to activate it.
• Click OK to save settings and close preferences.

Installing the Eclipse plug-ins

We will start with a clean version of Eclipse 3.6.1 from Eclipse’s download page and install the plug-ins we need.

• Open a browser and go to http://www.eclipse.org/downloads
• Download the package named:  Eclipse IDE for Java EE Developers
• Unpack the downloaded package in the location of your choice and start Eclipse.
• Open up Install New Software under the Help menu.
• Add two update sites
  1. SpringSource update site for Eclipse 3.6 Release http://dist.springsource.com/release/TOOLS/update/e3.6
  2. SpringSource update site for Eclipse 3.6 Release dependencies http://dist.springsource.com/release/TOOLS/composite/e3.6
• Back in the Install New Software window, choose to work with: SpringSource update site for Eclipse 3.6 Release
• Select SpringSource Tool Suite Grails Support under the category Extensions / STS
• Press the Next button and follow the wizard to complete the installation. The installation might seem to be stuck at zero percent for a couple of minutes, just be patient. You will also get a warning that you are trying to install unsigned content which is normal in this case.
• Restart Eclipse
• You might get a question about uploading data to SpringSource with Spring User Agent Analysis, which you can answer in the way you want.

Adding the Grails framework

To make the plug-ins work we also need to download the Grails framework.

• Open up a browser and go to http://www.grails.org/Download
• Choose to download version 1.3.6 Binary Zip
• Unpack the Grails framework where you like to store your development tools e.g. c:\tools
• Add an environment variable GRAILS_HOME that points to your Grails installation folder (Not mandatory when running Grails inside Eclipse) GRAILS_HOME=c:\tools\grails-1.3.6
• Also update the PATH environment variable to point at ${GRAILS_HOME}\bin (Not mandatory when running Grails inside Eclipse) PATH=%PATH%;%GRAILS_HOME%\bin
• In Eclipse, go to Preferences/Groovy/Grails and Add…
• Enter Grails in the Name field.
• Press Browse… and point out the the root folder of your unzipped your Grails framework e.g. c:\tools\grails-1.3.6
• Press OK.

Your Eclipse environment is now ready for developing Groovy and Grails applications.

Simple Groovy script to test your setup

Follow these steps to perform a simple test to see that Groovy now works inside Eclipse. As a side effect you also get a shortcut to a great tool for trying out groovy scripts, the Groovy Console.

Enter the Grails perspective

You should now have a Grails perspective in Eclipse.

• Choose Open Perspective/Other… from the Window menu
• Select Grails and click OK

Create a Groovy project

• Right click in the Project Explorer and open New/Other…
• Select Groovy Project and click Next
• Add a project name e.g. GroovyConsole and click Finish

Create a Groovy class

• Right click your project named GroovyConsole and open New/Other…
• Select Groovy Class and click Next
• Enter GroovyConsole in the name field, check the Create Script select box and click Finish
• Open the newly created file GroovyConsole.groovy and insert the following code:

import groovy.ui.Console
def console = new Console()
console.run()

• Save the file.

Run the Groovy class

Right click GroovyConsole.groovy and click on Run As/Groovy Script

• You shall now get a Groovy Console opened which verifies that Groovy is working inside Eclipse. You can also use the Groovy Console for testing groovy scripts.

Links and references

For more information about the technologies and tools used in this article there is more to read on these locations:

• Groovy – http://groovy.codehaus.org/
• Grails – http://www.grails.org/
• SpringSource Tool Suite – http://www.springsource.com/developer/sts
• Eclipse – http://www.eclipse.org/