/*
* Copyright 2002-2011 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.method.annotation;
import org.springframework.core.MethodParameter;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
import org.springframework.web.method.support.ModelAndViewContainer;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.SmartView;
import org.springframework.web.servlet.View;
/**
* Handles return values of type {@link ModelAndView} copying view and model
* information to the {@link ModelAndViewContainer}.
*
* <p>If the return value is {@code null}, the
* {@link ModelAndViewContainer#setRequestHandled(boolean)} flag is set to
* {@code false} to indicate the request was handled directly.
*
* <p>A {@link ModelAndView} return type has a set purpose. Therefore this
* handler should be configured ahead of handlers that support any return
* value type annotated with {@code @ModelAttribute} or {@code @ResponseBody}
* to ensure they don't take over.
*
* @author Rossen Stoyanchev
* @since 3.1
*/
public class ModelAndViewMethodReturnValueHandler implements HandlerMethodReturnValueHandler {
public boolean supportsReturnType(MethodParameter returnType) {
return ModelAndView.class.isAssignableFrom(returnType.getParameterType());
}
public void handleReturnValue(
Object returnValue, MethodParameter returnType,
ModelAndViewContainer mavContainer, NativeWebRequest webRequest)
throws Exception {
if (returnValue == null) {
mavContainer.setRequestHandled(true);
return;
}
ModelAndView mav = (ModelAndView) returnValue;
if (mav.isReference()) {
String viewName = mav.getViewName();
mavContainer.setViewName(viewName);
if (viewName != null && viewName.startsWith("redirect:")) {
mavContainer.setRedirectModelScenario(true);
}
}
else {
View view = mav.getView();
mavContainer.setView(view);
if (view instanceof SmartView) {
if (((SmartView) view).isRedirectView()) {
mavContainer.setRedirectModelScenario(true);
}
}
}
mavContainer.addAllAttributes(mav.getModel());
}
}