Spring Framework

org.springframework.web.portlet
Interface HandlerAdapter

All Known Implementing Classes:
AnnotationMethodHandlerAdapter, SimpleControllerHandlerAdapter, SimplePortletHandlerAdapter

public interface HandlerAdapter

Portlet MVC framework SPI interface, allowing parameterization of core MVC workflow.

Interface that must be implemented for each handler type to handle a request. This interface is used to allow the DispatcherPortlet to be indefinitely extensible. The DispatcherPortlet accesses all installed handlers through this interface, meaning that it does not contain code specific to any handler type.

Note that a handler can be of type Object. This is to enable handlers from other frameworks to be integrated with this framework without custom coding.

This interface is not intended for application developers. It is available to handlers who want to develop their own web workflow.

Note: Implementations can implement the Ordered interface to be able to specify a sorting order and thus a priority for getting applied by DispatcherPortlet. Non-Ordered instances get treated as lowest priority.

Since:
2.0
Author:
John A. Lewis
See Also:
SimpleControllerHandlerAdapter

Method Summary
 void handleAction(javax.portlet.ActionRequest request, javax.portlet.ActionResponse response, java.lang.Object handler)
          Use the given handler to handle this action request.
 void handleEvent(javax.portlet.EventRequest request, javax.portlet.EventResponse response, java.lang.Object handler)
          Use the given handler to handle this event request.
 ModelAndView handleRender(javax.portlet.RenderRequest request, javax.portlet.RenderResponse response, java.lang.Object handler)
          Use the given handler to handle this render request.
 ModelAndView handleResource(javax.portlet.ResourceRequest request, javax.portlet.ResourceResponse response, java.lang.Object handler)
          Use the given handler to handle this resource request.
 boolean supports(java.lang.Object handler)
          Given a handler instance, return whether or not this HandlerAdapter can support it.
 

Method Detail

supports

boolean supports(java.lang.Object handler)
Given a handler instance, return whether or not this HandlerAdapter can support it. Typical HandlerAdapters will base the decision on the handler type. HandlerAdapters will usually only support one handler type each.

A typical implementation:

return (handler instanceof MyHandler);

Parameters:
handler - handler object to check
Returns:
whether or not this object can use the given handler

handleAction

void handleAction(javax.portlet.ActionRequest request,
                  javax.portlet.ActionResponse response,
                  java.lang.Object handler)
                  throws java.lang.Exception
Use the given handler to handle this action request. The workflow that is required may vary widely.

Parameters:
request - current action request
response - current action response
handler - handler to use. This object must have previously been passed to the supports method of this interface, which must have returned true.
Throws:
java.lang.Exception - in case of errors
See Also:
Portlet.processAction(javax.portlet.ActionRequest, javax.portlet.ActionResponse)

handleRender

ModelAndView handleRender(javax.portlet.RenderRequest request,
                          javax.portlet.RenderResponse response,
                          java.lang.Object handler)
                          throws java.lang.Exception
Use the given handler to handle this render request. The workflow that is required may vary widely.

Parameters:
request - current render request
response - current render response
handler - handler to use. This object must have previously been passed to the supports method of this interface, which must have returned true.
Returns:
ModelAndView object with the name of the view and the required model data, or null if the request has been handled directly
Throws:
java.lang.Exception - in case of errors
See Also:
Portlet.render(javax.portlet.RenderRequest, javax.portlet.RenderResponse)

handleResource

ModelAndView handleResource(javax.portlet.ResourceRequest request,
                            javax.portlet.ResourceResponse response,
                            java.lang.Object handler)
                            throws java.lang.Exception
Use the given handler to handle this resource request. The workflow that is required may vary widely.

Parameters:
request - current render request
response - current render response
handler - handler to use. This object must have previously been passed to the supports method of this interface, which must have returned true.
Returns:
ModelAndView object with the name of the view and the required model data, or null if the request has been handled directly
Throws:
java.lang.Exception - in case of errors
See Also:
ResourceServingPortlet.serveResource(javax.portlet.ResourceRequest, javax.portlet.ResourceResponse)

handleEvent

void handleEvent(javax.portlet.EventRequest request,
                 javax.portlet.EventResponse response,
                 java.lang.Object handler)
                 throws java.lang.Exception
Use the given handler to handle this event request. The workflow that is required may vary widely.

Parameters:
request - current action request
response - current action response
handler - handler to use. This object must have previously been passed to the supports method of this interface, which must have returned true.
Throws:
java.lang.Exception - in case of errors
See Also:
EventPortlet.processEvent(javax.portlet.EventRequest, javax.portlet.EventResponse)

Spring Framework