org.springframework.web.portlet.mvc

Interface Controller

All Known Implementing Classes:

AbstractController, ParameterizableViewController, PortletModeNameViewController, PortletWrappingController

public interface Controller

Base portlet Controller interface, representing a component that receives RenderRequest/RenderResponse and ActionRequest/ActionResponse like a Portlet but is able to participate in an MVC workflow.

Any implementation of the portlet Controller interface should be a reusable, threadsafe class, capable of handling multiple portlet requests throughout the lifecycle of an application. To be able to configure Controller(s) in an easy way, Controllers are usually JavaBeans.

Workflow:

After the DispatcherPortlet has received a request and has done its work to resolve locales, themes and suchlike, it tries to resolve a Controller to handle that request, using a HandlerMapping. When a Controller has been found, the handleRenderRequest or handleActionRequest method will be invoked, which is responsible for handling the actual request and - if applicable - returning an appropriate ModelAndView. So actually, these method are the main entrypoint for the DispatcherPortlet which delegates requests to controllers.

So basically any direct implementation of the Controller interface just handles RenderRequests/ActionRequests and should return a ModelAndView, to be further used by the DispatcherPortlet. Any additional functionality such as optional validation, form handling, etc should be obtained through extending one of the abstract controller classes mentioned above.

Since:

2.0

Author:

William G. Thompson, Jr., John A. Lewis

See Also:

ResourceAwareController, EventAwareController, SimpleControllerHandlerAdapter, AbstractController, PortletContextAware

Method Summary

Modifier and Type	Method and Description
void	handleActionRequest(ActionRequest request, ActionResponse response) Process the action request.
ModelAndView	handleRenderRequest(RenderRequest request, RenderResponse response) Process the render request and return a ModelAndView object which the DispatcherPortlet will render.

Method Detail

handleActionRequest

void handleActionRequest(ActionRequest request,
                         ActionResponse response)
                  throws Exception

Process the action request. There is nothing to return.

Parameters:

request - current portlet action request

response - current portlet action response

Throws:

Exception - in case of errors

handleRenderRequest

ModelAndView handleRenderRequest(RenderRequest request,
                                 RenderResponse response)
                          throws Exception

Process the render request and return a ModelAndView object which the DispatcherPortlet will render. A null return value is not an error: It indicates that this object completed request processing itself, thus there is no ModelAndView to render.

Parameters:

request - current portlet render request

response - current portlet render response

Returns:

a ModelAndView to render, or null if handled directly

Throws:

Exception - in case of errors