Let me lead with the fact that I don't understand Spring Web MVC well enough.
That said, I think I have some concerns with the CredentialsBinder API and its associated LoginController implementation.
LoginController extends Spring SimpleFormHandler and looks something like this:
protected ModelAndView processFormSubmission(final HttpServletRequest request, final HttpServletResponse response, final Object object,
final BindException errors) throws Exception {
final Credentials credentials = (Credentials)object;
this.credentialsBinder.bind(request, credentials);
final String ticketGrantingTicketId = this.centralAuthenticationService.createTicketGrantingTicket(credentials);
/**
* Interface for a class that can bind items stored in the request to a particular
* credentials implementation. This allows for binding beyond the basic
* JavaBean/Request parameter binding that is handled by Spring automatically.
*
* @author Scott Battaglia
* @version $Id: CredentialsBinder.java,v 1.3 2005/01/25 20:19:12 sbattaglia Exp $
*
*/
public interface CredentialsBinder {
/**
* Method to allow manually binding attributes from the request object to properties of
* the credentials. Useful when there is no mapping of attribute to property for the
* usual Spring binding to handle.
*
* @param request The HttpServletRequest from which we wish to bind credentials to
* @param credentials The credentials we will be doing custom binding to.
*/
void bind(HttpServletRequest request, Credentials credentials);
/**
*
* Method to determine if a CredentialsBinder supports a specific class or not.
*
* @param clazz The class to determine is supported or not
* @return true if this class is supported by the CredentialsBinder, false otherwise.
*/
boolean supports(Class clazz);
}