FAQ : J2EE Pattern Interview Questions - Front Controller

Define Front controller pattern
Using a single component to process application requests.

Where to use & benefits
JSP or Servlet.
Design request handling component.
Channel all requests through a single controller.
Centralize request processing and view selection.
Reduce business logic in a view
Improve manageability of security
Promote code reuse across requests
Avoid code duplication

Related patterns include
Command combined with multiple requests.
Intercepting Filter both centralize control of certain types of request processing.
Page Controller -- an alternative way.

Example front controller pattern
Design a servlet to deal with all the requests. (Just like struts controller)