Boost Java Web Development Speed: Step-by-Step JRebel Installation Guide

JRebel Installation

In Java web development, updating a Java file usually requires restarting Tomcat, which wastes time. JRebel allows immediate hot‑deployment of class changes and Spring configuration, greatly improving efficiency.

Method 1: Add JRebel parameters to Tomcat startup

Extract JRebel to a directory, then configure IntelliJ IDEA's Tomcat settings.

In the Tomcat Server configuration, select the Deployment tab, choose your project with the exploded option, remove the default Make step, and add the following VM options.

-noverify
-agentpath:D:/dev_env/jrebel/jrebel_running/lib/jrebel64.dll

For Linux use:

-agentpath:/dev_env/jrebel/jrebel_running/lib/libjrebel64.so

For macOS use:

-agentpath:/dev_env/jrebel/jrebel_running/lib/libjrebel64.dylib

After configuring, start Tomcat. This method requires re‑configuring for each new project.

Method 2: Install JRebel IntelliJ IDEA plugin

Install the JRebel plugin locally (not via online marketplace). After installation, a JRebel configuration appears in Settings. Verify the plugin status shows VALID.

Two new green buttons appear next to the usual Run button: Run and Debug, which launch the application with JRebel enabled.

Custom container launch

When configuring a custom container, ensure the On 'Update' action and On frame deactivation options are set to Update classes and resources. Leave VM options empty and start the project, typically using the Debug button.

Maven or Gradle launch

Open the JRebel panel, select the project or module, and the plugin generates a rebel.xml in src/main/resources. Then launch the task from the Maven or Gradle tool window; after starting, recompile resources with Ctrl+Shift+F9 to apply changes.

JRebel offers a free trial key from its official website; register to obtain the activation key.