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Spring Mvc 3.1 之後如何配置messageConverters

<mvc:annotation-driven /> 是一種簡寫形式,完全可以手動配置替代這種簡寫形式,簡寫形式可以讓初學都快速應用預設配置方案。<mvc:annotation-driven /> 會自動註冊DefaultAnnotationHandlerMapping與AnnotationMethodHandlerAdapter 兩個bean,是spring MVC為@Controllers分發請求所必須的。

這句話我在很多帖子都看到過,我自己的專案本身使用的Spring MVC 3.2,實際上在3.1之後,<mvc:annotation-driven />註冊的類發生了變化

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

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <mvc:annotation-driven />

</beans>


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:

  1. Spring 3 style type conversion through a ConversionService instance in addition to the JavaBeans PropertyEditors used for Data Binding.

  2. Support for formatting Number fields using the @NumberFormat annotation through the ConversionService.

  3. Support for formatting Date, Calendar, Long, and Joda Time fields using the @DateTimeFormat annotation.

  4. Support for validating @Controller inputs with @Valid, if a JSR-303 Provider is present on the classpath.

  5. 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/from org.springframework.core.io.Resource for all media types.

    • SourceHttpMessageConverter converts to/from a javax.xml.transform.Source.

    • FormHttpMessageConverter converts form data to/from a MultiValueMap<String, String>.

    • Jaxb2RootElementHttpMessageConverter converts Java objects to/from XML — added if JAXB2 is present on the classpath.

    • MappingJackson2HttpMessageConverter (or MappingJacksonHttpMessageConverter) 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.

這是摘取的官方文件,可以看出,註冊的類已經變成了RequestMappingHandlerMapping和RequestMappingHandlerAdapter。

我之前在不知道的時候,使用AnnotationMethodHandlerAdapter 進行配置,結果在有<mvc:annotation-driven />存在的情況下,我自己配置的AnnotationMethodHandlerAdapter 怎麼都不起作用,於是去掉了<mvc:annotation-driven />標籤,手動註冊了AnnotationMethodHandlerAdapter ,和DefaultAnnotationHandlerMapping。結果引發了其他問題,比如檔案無法上傳的問題。

閱讀文件發現Spring提供了基於<mvc:annotation-driven />自定義messageConverters的方法,如下所示:

<mvc:annotation-driven conversion-service="conversionService">
    <mvc:message-converters>
        <bean class="org.example.MyHttpMessageConverter"/>
        <bean class="org.example.MyOtherHttpMessageConverter"/>
    </mvc:message-converters>
</mvc:annotation-driven>

下面展示我自己的配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
	xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:mvc="http://www.springframework.org/schema/mvc"
	xmlns:util="http://www.springframework.org/schema/util"
	xsi:schemaLocation="http://www.springframework.org/schema/beans
                     http://www.springframework.org/schema/beans/spring-beans.xsd
                     http://www.springframework.org/schema/tx
                     http://www.springframework.org/schema/tx/spring-tx.xsd
                     http://www.springframework.org/schema/context 
                     http://www.springframework.org/schema/context/spring-context.xsd
                     http://www.springframework.org/schema/aop
                     http://www.springframework.org/schema/aop/spring-aop.xsd
                     http://www.springframework.org/schema/jdbc
                     http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd
                     http://www.springframework.org/schema/util      
          			 http://www.springframework.org/schema/util/spring-util-3.2.xsd
                     http://www.springframework.org/schema/mvc 
  					 http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">

	<!-- spring自動掃描註解的元件 -->
	<context:component-scan base-package="cn.xx.xx"
		use-default-filters="false">
		<context:include-filter expression="org.springframework.stereotype.Controller"
			type="annotation" />
	</context:component-scan>

	<mvc:annotation-driven>
		<mvc:message-converters>
			<ref bean="stringHttpMessageConverter" />
			<ref bean="fastJsonHttpMessageConverter" />
			<ref bean="marshallingHttpMessageConverter" />
		</mvc:message-converters>
	</mvc:annotation-driven>

	<bean id="stringHttpMessageConverter"
		class="org.springframework.http.converter.StringHttpMessageConverter">
		<constructor-arg value="UTF-8" index="0"></constructor-arg><!-- 
			避免出現亂碼 -->
		<property name="supportedMediaTypes">
			<list>
				<value>text/plain;charset=UTF-8</value>
			</list>
		</property>
	</bean>
	<bean id="fastJsonHttpMessageConverter"
		class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter">

		<property name="supportedMediaTypes">
			<list>
				<value>application/json;charset=UTF-8</value>
				<value>text/html;charset=UTF-8</value><!-- 避免IE出現下載JSON檔案的情況 -->
			</list>
		</property>
		<property name="features">
			<util:list>
				<!-- <value>WriteMapNullValue</value> -->
				<value>QuoteFieldNames</value>
				<value>WriteDateUseDateFormat</value>
			</util:list>
		</property>
	</bean>
	
	<bean id="marshallingHttpMessageConverter"
		class="org.springframework.http.converter.xml.MarshallingHttpMessageConverter">
		<property name="marshaller" ref="castorMarshaller" />
		<property name="unmarshaller" ref="castorMarshaller" />
		<property name="supportedMediaTypes">
			<list>
				<value>text/xml;charset=UTF-8</value>
				<value>application/xml;charset=UTF-8</value>
			</list>
		</property>
	</bean>

	<!-- 返回型別定義 -->
	<util:list id="messageConverters">
		<ref bean="stringHttpMessageConverter" />
		<ref bean="fastJsonHttpMessageConverter" />
		<ref bean="marshallingHttpMessageConverter" />
	</util:list>

	<bean id="castorMarshaller" class="org.springframework.oxm.castor.CastorMarshaller" />

	<!-- AOP自動註解功能 -->
	<aop:aspectj-autoproxy />

	<!-- 不進行攔截的 -->
	<mvc:resources location="/" mapping="/**/*.html" order="0" />
	<mvc:resources location="/images/" mapping="/images/**" />
	<mvc:resources location="/img/" mapping="/img/**" />
	<mvc:resources location="/download/" mapping="/download/**" />

	<mvc:resources location="/js/" mapping="/js/**" />
	<mvc:resources location="/css/" mapping="/css/**" />
	<mvc:resources location="/plugin/" mapping="/plugin/**" />
	<mvc:resources location="/WEB-INF/pages/" mapping="/pages/**" />

	<bean id="messageSource"
		class="org.springframework.context.support.ResourceBundleMessageSource">
		<property name="basename" value="messages"></property>
	</bean>

	<bean
		class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/WEB-INF/pages/" />
		<property name="suffix" value=".jsp" />

	</bean>

	<!-- 支援上傳檔案 -->
	<bean id="multipartResolver"
		class="org.springframework.web.multipart.commons.CommonsMultipartResolver" />

	<!-- restTemplate -->
	<bean id="restTemplate" class="org.springframework.web.client.RestTemplate">
		<property name="messageConverters" ref="messageConverters">
		</property>
	</bean>
</beans>