Vaadin development write code/test iteration and the need to restart the se


I am very new to Vaadin but I have experience with GWT, even though I am not too sure this helps me much.

I have a question about development iterations, write code - test changes cycles. I am using IntellijIdea 15. When I develop in GWT one of the things that I love about it is that, when I work on the UI code, I can save the code in the editor, then I refresh the page in the browser and the page shows the latest changes. I don’t need to restart the server or recompile all the code.

Is this possible with Vaadin as well? I created a hello world type app using Vaadin and I use Jetty as web server. After I changed the message displayed upon clicking a button, I had to re-compile and restart Jetty to have the change show up in the page. It doesn’t add much time, but when you do it a lot there is some lost time. Plus I kind of like the almost instant feedback.


If you run Jetty in debug mode, the IDE should be able to hot-deploy certain changes (mostly inside methods) but not nearly all (like adding fields, methods, classes, …)

Instead of restarting Jetty every time, you can configure a scanInterval for Jetty so it will pick up changes itself. Then all you have to do is refresh after a few seconds when Jetty has picked up the changes.

If you happen to have JRebel license, that will provide you with a much better hot deploy functionality than the standard Java version.

Thank you for your recommendations. I wish I knew about jrebel 5 years ago :slight_smile:

If you haven’t JRebel you can try DCE VM
an open source fork of the JVM with better hotswapping capabilities.