Reload Any Changes
Reload Java classes
See all changes to Java code instantly in the browser. Save and refresh! The same is true for your other project files.
Reload framework configurations
While most of the application logic is implemented in Java code, it is every so often the case that the real applications are created by using frameworks. In most cases, the frameworks rely on configuration of some sort. JRebel can handle configuration changes for a wide range of frameworks to keep you productive.
See full list of supported frameworks…
Skip the Build
Compile from the IDE
Compiling Java code in modern IDEs is blazingly quick. It’s the other phases of the build that make it last forever.
With JRebel all classes and resources are loaded directly from the workspace. No more time spent on building WAR/EAR archives, resolving dependencies, etc.
Modules not a problem
Do you have a 100 modules assembled by Maven? Not a problem – JRebel will map each module individually to its deployment artifact and any change saved in the IDE will be immediately reflected in the browser.
Work Remotely or
in the Cloud
Reload webapp changes remotely
Used to working with a remote development server? Then you know how painful it can be. With JRebel, run your application locally, remotely or in the cloud and see code and configuration changes instantly.
Sync over HTTP
No need to open new ports or worry about firewalls – JRebel Remoting works with the same HTTP connection that your web app runs on.
Learn more about remoting
Start using in Minutes
Use your favourite IDE
JRebel can be installed as a plugin to all major IDEs, including Eclipse, Rational Application Developer, MyEclipse, IntelliJ IDEA, NetBeans IDE and JDeveloper.
Our IDE plugins will generate all the necessary configuration from your project definitions. So will our Maven and Gradle plugins. And you can share the configuration with all of your team.
Some Overhead Expected
< 50 % startup-time overhead
JRebel will instrument all your application classes at load-time so somewhat longer startup time is to be expected. You will make up for it by restarting way less.
< 10 % CPU overhead
To allow methods to be added to classes, JRebel introduces some indirection on method calls that causes minor overhead.
< 2x PermGen overhead
Classes are bigger with JRebel, so it’s a good idea to double your PermGen setting, and if you have nothing at the moment add -XX:PermGen=128m to your JVM command line.
Broad Ecosystem Support
Popular industry frameworks
Spring and Hibernate are supported by JRebel as the de-facto industry standards for Java application development. You can add new beans, change injection configurations, add new OR mappings on the fly without having to restart your applications.
Extensive support for Java EE technologies
All the Java EE technologies like JSF, CDI, JAXB, JPA, JAX-RS, JAX-WS rely on configuration of some sort, either annotations or XML files. JRebel makes it easy to work with Java EE by gracefully handling a wide range configuration changes.