How to install and use JRebel (formerly JavaRebel) in GlassFish with Eclipse IDE
In the recently published Java EE Container Restart & Redeploy Report, the GlassFish v2 application container was the best of the fully fledged Java EE containers in the terms of time spent redeploying. That’s the good news. The not so good news is that on average respondents report spending 14% of their coding time waiting for server redeploys/restarts. That’s just over 170 hours annually, per developer – approximately 4.3 full weeks of development time. JRebel eliminates the need to redeploy in about 80% of redeploy situations – and it’s easy to get started. This tutorial explains how to install and use it step-by-step.
Here we assume that you are using Eclipse 3.x with GlassFish v2. Most of the steps will be applicable to other versions as well, but it may look different from the screenshots included.
NOTE: Although GlassFish is tightly integrated with NetBeans, the JRebel support for that IDE is in Beta at the moment – for now, we recommend using Eclipse or IntelliJ IDEA instead. We’ll make sure to announce when better NetBeans support is available (it’s coming soon).
First, take a quick look at how coding looks when using JRebel (formerly JavaRebel).
Contents:
- STEP 1: Install JRebel
- STEP 2: Installing JRebel Eclipse IDE plugin
- STEP 3: Make a rebel.xml for your application
- STEP 4: Configuring the Eclipse WTP IDE
- STEP 5: Configuring Eclipse IDE
- STEP 6: Success!
STEP 1: Install JRebel
The latest stable version of JRebel can be downloaded here. Unpack it to a directory of your choice.
STEP 2: Installing JRebel Eclipse IDE plugin
The JRebel Eclipse IDE plugin was introduced with JRebel 2.0 and makes configuring and using JRebel considerably easier. You can install the plugin by going to Help » Software updates » Available software » Add site and use the http://www.zeroturnaround.com/update-site/ URL as the update site.
STEP 3: Make a rebel.xml for your application
In order to do it’s magic, JRebel needs to know where your classes and resources are. We’ll use a rebel.xml configuration file to tell it. This is mandatory when you deploy your app as a WAR/EAR. You’ll need to have one rebel.xml file per module. This includes both web and EJB modules. The rebel.xml configuration file should be placed in your WEB-INF/classes directory in the case of a web module and in the jar root in the case of an ejb module. Put it in the root of a source or resource folder in your project (the same place where the .properties files are).
If you use Maven you can use the JRebel Maven plugin that will generate the rebel.xml in accordance with the module pom.xml as described in the Maven Plugin configuration manual.
In 99% of cases, people tend to use one module per project. In these cases, the JRebel Eclipse IDE plugin can generate the rebel.xml file for you, on a per project basis. If your project is one of the exceptions, edit the file manually as described in the Installation manual, otherwise generate the rebel.xml like this:
Click on your project and pick Generate rebel.xml
STEP 4: Configuring the Eclipse WTP IDE
You may skip this step if you run GlassFish outside of the Eclipse IDE.
Open the Servers View and double click the GlassFish v2 that your application is deployed to (if you don’t see the Servers View go to Window » Show View » Servers).
Open Publishing and choose Never publish automatically.
It may seem wrong to disable automatic publishing, but as JRebel will take care of updates from now on it will just slow you down.
STEP 5: Configuring Eclipse IDE
Go to Window » Preferences and from there to Java » Debug » Step Filtering. Check Use Step Filters and Filter synthetic methods and Step through filters. Now check all the default filters and use the Add Filter button to add com.zeroturnaround.* and org.zeroturnaround.*.
Now go to Project » Build automatically and make sure it is checked.
STEP 6: Success!
To check that the installation was successful access a page that uses a class, change that class in the IDE, press Save, access the page again and look for the following message in the console:
Now that you’re up and running, it’s time to enjoy coding without the need to redeploy. If you have any specific questions JRebel, the Forum is the best place to ask, so that other people get to hear the answer as well. Otherwise, you can contact us at support@zeroturnaround.com.
If you like what you see, please give us a quick mention on your blog or twitter (you can even follow us here).
Have a great day!
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