1) A request comes in from a Java Server Page into the
ActionServlet.
2) The ActionServlet having already read the
struts-config.xml file, knows which form bean
relates to this JSP, and delegates work to the validate
method of that form bean.
3) The form bean performs the validate method to determine
if all required fields have been entered, and performs
whatever other types of field validations that need to be
performed.
4) If any required field has not been entered, or any field
does not pass validation, the form bean generates
ActionErrors, and after checking all fields returns back to
the ActionServlet.
5) The ActionServlet checks the ActionErrors that were
returned from the form bean’s validate method to determine
if any errors have occurred. If errors have occurred, it
returns to the originating JSP displaying the appropriate
errors.
6) If no errors occurred in the validate method of the form
bean, the ActionServlet passes control to the appropriate
Action class.
7) The Action class performs any necessary business logic,
and then forwards to the next appropriate action (probably
another JSP).