Hi,
I try Vaadin. I display the client application in a web navigator. When I do a modification in the JAVA source code and I display again the client application in the web navigator, the changes are not displayed.
When I restart the server, the changes are displayed.
How can I display the modfication without restart the server at all time ?
Thank.
Bye. 
Have you tried JRebel: http://zeroturnaround.com/software/jrebel/
JSPs can be configured to be recompiled on each request, but thatās never been the case for .class/.jar files (well, except with JRebel type solutions), and of course widgetset Java code has to be recompiled to javascript and then sent to the browser again, so thereās no 100% solution.
I would second Davidās recommendation of JRebel, but checking to make sure you have added ā?restartApplicationā to your URL if using Vaadin 6 or @PreserveOnRefresh annotation with Vaadin 7. Otherwise, the application is not recreated on reload even if some code changes might be effective also without JRebel.
JRebel does not eliminate the need for restarts completely, but does reduce them a lot.
It sounds like your application server (or the tool youāre using for deplyment) has a feature turned on to preserve sessions on redeployment. The fastest thing is to find that setting and turn it off.
Otherwise, restarting the app is the way to go.
This little blog
might save you a few seconds when restarting.
Cheers,
Bobby
Thank for the answers.