Feature Flexibility

Hi,

I have a web application which is using a MVC pattern it uses XML/XSL for view, servlet as controller and simple POJOs for Model. Different user belonging to different clients log into the application. I am developing a new feature which should be accessible to users belonging to one of the clients client, an existing screen will be modified to achieve this. This feature should be configurable i.e. if users belonging to other clients demand this feature then we should be able to easily enable it for them.

I need inputs on how to make this configurable. Keep a config file or database table or something else.

Thanks in advance.

Regards