What is the best approach to create a role based web application?

I need to create a web application for a School and I need to have different roles such as:

• Student
• Professor
• Admin

I need to have a login at the beginning and then after entering the credentials the application needs to redirect to the home page.

The question here is: How should I handle the roles? Should I have a namespace for each role? i.e: students/index.jsp, professors/index.jsp, admin/index.jsp or have a common namespace for all roles? something like home/index.jsp? and then use decorator/strategy pattern to have the menus have different options based on the role?

Thank you for your time and help.