Instance of application

I have a problem, when I deploy my application on a server and I connect me on, it works perfect. But if my colleague connect him, my application doesn’t work, when I click on a button, the changment happens on his application??
Do you know what can happen??


It seems it uses only one instance for 2 users. Is there a bug ? I noticed we used some static variable in our Application.
Maybe it can come from it ?

Static variables are shared by all application instances running in your JVM. When you want to have something available to one application instance only, put it in the application instance and do not make it static.

Thx for ur advices. Indeed there were some static variable we removed.

Now all is Ok !