org.springframework.web.servlet.mvc.throwaway.ThrowawayController Maven / Gradle / Ivy
/*
* Copyright 2002-2005 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.web.servlet.mvc.throwaway;
import org.springframework.web.servlet.ModelAndView;
/**
* ThrowawayController is an alternative to Spring's default Controller interface,
* for executable per-request command instances that are not aware of the Servlet API.
* In contrast to Controller, implementing beans are not supposed to be defined as
* Servlet/Struts-style singletons that process a HttpServletRequest but rather as
* WebWork/Maverick-style prototypes that get populated with request parameters,
* executed to determine a view, and thrown away afterwards.
*
* The main advantage of this controller programming model is that controllers
* are testable without HttpServletRequest/HttpServletResponse mocks, just like
* WebWork actions. They are still web UI workflow controllers: Spring does not
* aim for the arguably hard-to-achieve reusability of such controllers in non-web
* environments, as XWork (the generic command framework from WebWork2) does
* but just for ease of testing.
*
*
A ThrowawayController differs from the command notion of Base- or
* AbstractCommandController in that a ThrowawayController is an executable
* command that contains workflow logic to determine the next view to render,
* while BaseCommandController treats commands as plain parameter holders.
*
*
If binding request parameters to this controller fails, a fatal BindException
* will be thrown.
*
*
If you need access to the HttpServletRequest and/or HttpServletResponse,
* consider implementing Controller or deriving from AbstractCommandController.
* ThrowawayController is specifically intended for controllers that are not aware
* of the Servlet API at all. Accordingly, if you need to handle session form objects
* or even wizard forms, consider the corresponding Controller subclasses.
*
* @author Juergen Hoeller
* @since 08.12.2003
* @see org.springframework.web.servlet.mvc.Controller
* @see org.springframework.web.servlet.mvc.AbstractCommandController
*/
public interface ThrowawayController {
/**
* Execute this controller according to its bean properties.
* Gets invoked after a new instance of the controller has been populated with request
* parameters. Is supposed to return a ModelAndView in any case, as it is not able to
* generate a response itself.
* @return a ModelAndView to render
* @throws Exception in case of errors
*/
ModelAndView execute() throws Exception;
}