RequestProcessor Class is the actual place where the request processing takes place in a Struts controller environmentStruts Documentation
When the request object first reaches the actionservlet class ,it invokes the process method of the underlying RequestProcessor Class.
This process method then looks into the struts-config.xml file and tries to locate the name of the action that has come with the request.Once it identifies the action class in the struts-config.xml file and invokes the execute() method of the corresponding Action class
RequestProcessor Class has the following responsibilities:
1. Resolve url,
2. Identifies proper Action which process request,
3. If any form beans available which create instance of formbean,
4. If validations necessary do validations,
5. Call execute() of Action,
6. Depending on response generated by execute() method which invoke proper view components