This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
The ActionServlet is the main controller object. It gets control as soon as a user requests "myAction.do". The RequestProcessor is a helper class instantiated and used by ActionServlet to process each request that comes in. The RequestProcessor actually does most of the work involved when a request comes in and a response goes out.