Downloading JRebel 2023.3.2 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. This software for Mac OS X was originally created by ZeroTurnaround. We recommend checking the downloaded files with any free antivirus. The software lies within Developer Tools, more precisely Debugging Tools.
From the developer:
JRebel tracks Java application development by skipping the time consuming build and redeploy steps in the development process. Developers keep their tempo and focus by eliminating the downtime normally spent waiting for application build and redeploy. No more interrupt driven development.
You may want to check out more software for Mac, such as eclipse-php, Prototypes or KBSwitch, which might be similar to JRebel.