Java Web Application - Admin/Public Users

Java Web Application - Admin/Public Users

Consider a Simple Java Web Application which has login and registration
functionality using JSP, Servlets, JDBC, JSTL. I need to make the
application have normal public_users, and then admins. They both utilize
the same login page, although when a public user log's in, it has
different dashboard utilities, compared to the administrator's when they
login.
I have tried searching on Google, although I have not been able to find a
concrete answer.
Is it possible to have these two users utilize the same login page? If any
of the users have valid credentials, based on the status 'admin' or
'public_user' Is there a way of redirecting them to 2 totally different
pages?
Within the database, how would I set a particular user to admin, or invite
someone to be an administrator?
Suggestions would be appreciated, Thank you