如何为IntelliJ中Gradle+Tomcat插件配置JRebel实现热部署

Hey there! Let's get your JRebel hot-deployment up and running with your Gradle + Tomcat setup. I'll break down exactly where to modify the scripts and even share a more IDE-friendly approach since you're using IntelliJ:

First, the location depends on whether you're using a global Gradle installation or the Gradle Wrapper (the default for most projects):

• Windows:

  • Global Gradle: Find bin\gradle.bat in your Gradle install directory (e.g., C:\Gradle\gradle-4.3.1\bin\gradle.bat)
  • Gradle Wrapper: Look in your project root for gradlew.bat

  Add these lines early in the script (before the Java command is executed):

  @rem Set JRebel installation path
  set REBEL_HOME=C:\path\to\your\jrebel\folder
  @rem Add JRebel agent to JVM options
  set JAVA_OPTS="-javaagent:%REBEL_HOME%\jrebel.jar %JAVA_OPTS%"
  

• Linux/macOS:

  • Global Gradle: Find bin/gradle in your Gradle install directory (e.g., /usr/local/gradle-4.3.1/bin/gradle)
  • Gradle Wrapper: Look in your project root for gradlew

  Add these lines at the top of the script:

  # Set JRebel installation path
  export REBEL_HOME=/path/to/your/jrebel/folder
  # Add JRebel agent to JVM options
  export JAVA_OPTS="-javaagent:$REBEL_HOME/jrebel.jar $JAVA_OPTS"
  

Since you're launching Tomcat directly from IntelliJ, you don't need to mess with global scripts—configure it directly in your run/debug settings for better flexibility:

• Open Run > Edit Configurations in IntelliJ
• Find your Tomcat run configuration (it's tied to the tomcatRun or tomcatWarRun Gradle task from the bmuschko plugin)
• Switch to the Environment Variables tab:
  • Click the + button, add REBEL_HOME as the name, and paste your JRebel install path as the value
• Switch to the VM options field (under the Configuration tab) and add:

  -javaagent:$REBEL_HOME/jrebel.jar
  

• Save the configuration and restart your Tomcat instance

After starting Tomcat, check the console output. You should see logs like:

JRebel: Starting up...
JRebel: Monitoring changes in [path/to/your/src/main/webapp]

If you see these lines, go ahead and modify a file in your webapp folder—refresh your browser, and the changes should show up immediately without a full restart.

Make sure your rebel.xml in build/classes/main correctly points to your webapp directory. A basic valid config looks like this:

<?xml version="1.0" encoding="UTF-8"?>
<application xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xmlns="http://www.zeroturnaround.com"
             xsi:schemaLocation="http://www.zeroturnaround.com http://www.zeroturnaround.com/alderaan/rebel-2_0.xsd">
  <web>
    <link target="/">
      <dir name="src/main/webapp"/>
    </link>
  </web>
</application>

内容的提问来源于stack exchange，提问作者Al Phaba