Package org.springframework.web.servlet.mvc.method.annotation

Class ModelAndViewResolverMethodReturnValueHandler

java.lang.Object

org.springframework.web.servlet.mvc.method.annotation.ModelAndViewResolverMethodReturnValueHandler

All Implemented Interfaces:

HandlerMethodReturnValueHandler

public class ModelAndViewResolverMethodReturnValueHandler
extends Object
implements HandlerMethodReturnValueHandler

This return value handler is intended to be ordered after all others as it attempts to handle _any_ return value type (i.e. returns true for all return types).

The return value is handled either with a ModelAndViewResolver or otherwise by regarding it as a model attribute if it is a non-simple type. If neither of these succeeds (essentially simple type other than String), UnsupportedOperationException is raised.

Note: This class is primarily needed to support ModelAndViewResolver, which unfortunately cannot be properly adapted to the HandlerMethodReturnValueHandler contract since the HandlerMethodReturnValueHandler.supportsReturnType(org.springframework.core.MethodParameter) method cannot be implemented. Hence ModelAndViewResolvers are limited to always being invoked at the end after all other return value handlers have been given a chance. It is recommended to re-implement a ModelAndViewResolver as HandlerMethodReturnValueHandler, which also provides better access to the return type and method information.

Since:

3.1

Author:

Rossen Stoyanchev

Constructor Summary

Constructors

Constructor	Description
ModelAndViewResolverMethodReturnValueHandler(List<ModelAndViewResolver> mavResolvers)	Create a new instance.

Method Summary

Modifier and Type	Method	Description
void	handleReturnValue(Object returnValue, MethodParameter returnType, ModelAndViewContainer mavContainer, NativeWebRequest webRequest)	Handle the given return value by adding attributes to the model and setting a view or setting the ModelAndViewContainer.setRequestHandled(boolean) flag to true to indicate the response has been handled directly.
boolean	supportsReturnType(MethodParameter returnType)	Always returns true.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ModelAndViewResolverMethodReturnValueHandler

public ModelAndViewResolverMethodReturnValueHandler(@Nullable
 List<ModelAndViewResolver> mavResolvers)

Create a new instance.

Method Details

supportsReturnType

public boolean supportsReturnType(MethodParameter returnType)

Always returns true. See class-level note.

Specified by:

supportsReturnType in interface HandlerMethodReturnValueHandler

Parameters:

returnType - the method return type to check

Returns:

true if this handler supports the supplied return type; false otherwise

handleReturnValue

public void handleReturnValue(@Nullable
 Object returnValue,
 MethodParameter returnType,
 ModelAndViewContainer mavContainer,
 NativeWebRequest webRequest)
                       throws Exception

Description copied from interface: HandlerMethodReturnValueHandler

Handle the given return value by adding attributes to the model and setting a view or setting the ModelAndViewContainer.setRequestHandled(boolean) flag to true to indicate the response has been handled directly.

Specified by:

handleReturnValue in interface HandlerMethodReturnValueHandler

Parameters:

returnValue - the value returned from the handler method

returnType - the type of the return value. This type must have previously been passed to HandlerMethodReturnValueHandler.supportsReturnType(org.springframework.core.MethodParameter) which must have returned true.

mavContainer - the ModelAndViewContainer for the current request

webRequest - the current request

Throws:

Exception - if the return value handling results in an error