<mvc:annotation-driven /> 是一种简写形式,完全可以手动配置替代这种简写形式,简写形式可以让初学都快速应用默认配置方案。<mvc:annotation-driven /> 会自动注册DefaultAnnotationHandlerMapping与AnnotationMethodHandlerAdapter 两个bean,是spring MVC为@Controllers分发请求所必须的。
这句话我在很多帖子都看到过,我自己的项目本身使用的Spring MVC 3.2,实际上在3.1之后,<mvc:annotation-driven />注册的类发生了变化
Spring Framework 3.1 introduces a new set of support classes for processing requests with annotated controllers:
-
RequestMappingHandlerMapping
-
RequestMappingHandlerAdapter
-
ExceptionHandlerExceptionResolver
These classes are a replacement for the existing:
-
DefaultAnnotationHandlerMapping
-
AnnotationMethodHandlerAdapter
-
AnnotationMethodHandlerExceptionResolver
The above registers a RequestMappingHandlerMapping
, a RequestMappingHandlerAdapter
, and an ExceptionHandlerExceptionResolver
(among others) in support of processing requests with annotated controller methods using annotations such as @RequestMapping
, @ExceptionHandler
, and others.
It also enables the following:
-
Spring 3 style type conversion through a ConversionService instance in addition to the JavaBeans PropertyEditors used for Data Binding.
-
Support for formatting Number fields using the
@NumberFormat
annotation through theConversionService
. -
Support for formatting Date, Calendar, Long, and Joda Time fields using the
@DateTimeFormat
annotation. -
Support for validating @Controller inputs with
@Valid
, if a JSR-303 Provider is present on the classpath. -
HttpMessageConverter support for
@RequestBody
method parameters and@ResponseBody
method return values from@RequestMapping
or@ExceptionHandler
methods.This is the complete list of HttpMessageConverters set up by mvc:annotation-driven:
-
ByteArrayHttpMessageConverter
converts byte arrays. -
StringHttpMessageConverter
converts strings. -
ResourceHttpMessageConverter
converts to/fromorg.springframework.core.io.Resource
for all media types. -
SourceHttpMessageConverter
converts to/from ajavax.xml.transform.Source
. -
FormHttpMessageConverter
converts form data to/from aMultiValueMap<String, String>
. -
Jaxb2RootElementHttpMessageConverter
converts Java objects to/from XML — added if JAXB2 is present on the classpath. -
MappingJackson2HttpMessageConverter
(orMappingJacksonHttpMessageConverter
) converts to/from JSON — added if Jackson 2 (or Jackson) is present on the classpath. -
AtomFeedHttpMessageConverter
converts Atom feeds — added if Rome is present on the classpath. -
RssChannelHttpMessageConverter
converts RSS feeds — added if Rome is present on the classpath.
-
RequestMappingHandlerMapping和
RequestMappingHandlerAdapter。
我之前在不知道的时候,使用AnnotationMethodHandlerAdapter 进行配置,结果在有<mvc:annotation-driven />存在的情况下,我自己配置的AnnotationMethodHandlerAdapter 怎么都不起作用,于是去掉了<mvc:annotation-driven />标签,手动注册了AnnotationMethodHandlerAdapter ,和DefaultAnnotationHandlerMapping。结果引发了其他问题,比如文件无法上传的问题。
阅读文档发现Spring提供了基于<mvc:annotation-driven />自定义messageConverters的方法,如下所示:
下面展示我自己的配置
http://blog.youkuaiyun.com/yfisaboy/article/details/31755631