java.lang.Object
   org.springframework.context.support.ApplicationObjectSupport
      org.springframework.web.context.support.WebApplicationObjectSupport
         org.springframework.web.servlet.support.WebContentGenerator
            org.springframework.web.servlet.mvc.AbstractController

All Implemented Interfaces:
    Controller, ServletContextAware, ApplicationContextAware

Direct Known Subclasses:
    AbstractUrlViewController, AbstractWizardFormController, CancellableFormController, ParameterizableViewController, MultiActionController, BaseCommandController, SimpleFormController, AbstractClinicForm, ServletForwardingController, AbstractCommandController, AbstractFormController, UrlFilenameViewController, ServletWrappingController

Convenient superclass for controller implementations, using the Template Method design pattern.

As stated in the Controller interface, a lot of functionality is already provided by certain abstract base controllers. The AbstractController is one of the most important abstract base controller providing basic features such as the generation of caching headers and the enabling or disabling of supported methods (GET/POST).

Workflow (and that defined by interface):

1. handleRequest() will be called by the DispatcherServlet
2. Inspection of supported methods (ServletException if request method is not support)
3. If session is required, try to get it (ServletException if not found)
4. Set caching headers if needed according to cacheSeconds propery
5. Call abstract method handleRequestInternal() (optionally synchronizing around the call on the HttpSession), which should be implemented by extending classes to provide actual functionality to return ModelAndView objects.

Exposed configuration properties (and those defined by interface):

name	default	description
supportedMethods	GET,POST	comma-separated (CSV) list of methods supported by this controller, such as GET, POST and PUT
requireSession	false	whether a session should be required for requests to be able to be handled by this controller. This ensures that derived controller can - without fear of null pointers - call request.getSession() to retrieve a session. If no session can be found while processing the request, a ServletException will be thrown
cacheSeconds	-1	indicates the amount of seconds to include in the cache header for the response following on this request. 0 (zero) will include headers for no caching at all, -1 (the default) will not generate any headers and any positive number will generate headers that state the amount indicated as seconds to cache the content
synchronizeOnSession	false	whether the call to handleRequestInternal should be synchronized around the HttpSession, to serialize invocations from the same client. No effect if there is no HttpSession.

Also see:

WebContentInterceptor
author: Rod - Johnson

author: Juergen - Hoeller

 public ModelAndView handleRequest(HttpServletRequest request,
    HttpServletResponse response) throws Exception 
{
		// Delegate to WebContentGenerator for checking and preparing.
		checkAndPrepare(request, response, this instanceof LastModified);
		// Execute handleRequestInternal in synchronized block if required.
		if (this.synchronizeOnSession) {
			HttpSession session = request.getSession(false);
			if (session != null) {
				Object mutex = WebUtils.getSessionMutex(session);
				synchronized (mutex) {
					return handleRequestInternal(request, response);
				}
			}
		}
		return handleRequestInternal(request, response);
}

 abstract protected ModelAndView handleRequestInternal(HttpServletRequest request,
    HttpServletResponse response) throws Exception
Template method. Subclasses must implement this.
The contract is the same as for handleRequest.

 public final boolean isSynchronizeOnSession() 
{
		return this.synchronizeOnSession;
}

 public final  void setSynchronizeOnSession(boolean synchronizeOnSession) 
{
	                                                                                                                                                   	 
		this.synchronizeOnSession = synchronizeOnSession;
}