本文主要是进行springmvc与fastjson整合
1.在pom.xml配置fastjson:
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>${fastjson-version}</version>
</dependency>
2.web.xml配置：
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring/applicationContext.xml</param-value>
</context-param>
<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<servlet>
<servlet-name>springMVC</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring/springMVC-servlet.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springMVC</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>/index.jsp</welcome-file>
</welcome-file-list>
<error-page>
<error-code>404</error-code>
<location>/index.jsp</location>
</error-page>
3.springMVC-servlet.xml配置：
<context:component-scan base-package="com.ezubo.global.controller"/>
<mvc:default-servlet-handler/>
<mvc:annotation-driven >
<mvc:message-converters register-defaults="true">
<!-- <bean class="org.springframework.http.converter.StringHttpMessageConverter"/>-->
<!--
<bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"/>
-->
<bean class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter">
<property name="supportedMediaTypes" value="text/html;charset=UTF-8"/>
<!-- 转换时设置特性-->
<property name="features">
<array>
<!-- 避免默认的循环引用替换-->
<value>DisableCircularReferenceDetect</value>
<value>WriteNullStringAsEmpty</value>
<value>WriteNullNumberAsZero</value>
<value>WriteMapNullValue</value>
<!-- <ref bean="DisableCircularReferenceDetect"/>
<ref bean="WriteMapNullValue"/>
<ref bean="WriteNullStringAsEmpty"/>
<ref bean="WriteNullNumberAsZero"/>-->
</array>
</property>
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
<mvc:resources mapping="/css/**" location="/css/"/>
<mvc:resources mapping="/*.html" location="/"/>
<!-- enum枚举值的引用方法 -->
<bean id="DisableCircularReferenceDetect" class="org.springframework.beans.factory.config.FieldRetrievingFactoryBean" >
<property name="staticField" value="com.alibaba.fastjson.serializer.SerializerFeature.DisableCircularReferenceDetect"></property>
</bean>
<bean id="WriteNullStringAsEmpty" class="org.springframework.beans.factory.config.FieldRetrievingFactoryBean" >
<property name="staticField" value="com.alibaba.fastjson.serializer.SerializerFeature.WriteNullStringAsEmpty"></property>
</bean>
<bean id="WriteNullNumberAsZero" class="org.springframework.beans.factory.config.FieldRetrievingFactoryBean" >
<property name="staticField" value="com.alibaba.fastjson.serializer.SerializerFeature.WriteNullNumberAsZero"></property>
</bean>
<bean id="WriteMapNullValue" class="org.springframework.beans.factory.config.FieldRetrievingFactoryBean" >
<property name="staticField" value="com.alibaba.fastjson.serializer.SerializerFeature.WriteMapNullValue"></property>
</bean>
<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
<property name="prefix" value="/WEB-INF/jsp/"/>
<property name="suffix" value=".jsp"/>
</bean>
</beans>
<!-- fastjson-1.1.41与SpringMVC整合 -->
<!--
1)若按照jackson和SpringMVC的整合方式,应按照下面的写法,但测试发现这样会报告"HTTP Status 406"
The resource identified by this request is only capable of generating responses
with characteristics not acceptable according to the request "accept" headers.
2)测试通过的整合方式为上面那样在mvc:annotation-driven里面进行注册
3)supportedMediaTypes增加[text/html;charset=UTF-8]值,是为了兼容IE6
否则[application/json]值在IE6中会导致弹出对话框询问是否保存文件,而firefox等高级浏览器会正常打印json字符串
4)若像下面这样给supportedMediaTypes属性赋两个值[text/html;charset=UTF-8]和[application/json],则[application/json]是无效的
因为此时应答给浏览器(或者说请求方)的Content-Type头信息都是[text/html;charset=UTF-8],所以给它一个值就行了
如果给supportedMediaTypes的值为[application/json],则应答给浏览器的Content-Type头信息就是[application/json;charset=UTF-8]
5)关于features属性,不是serializerFeature,而是features,详见FastJsonHttpMessageConverter.java
它是用来控制json序列化输出时的一些额外属性,比如说该字段是否输出、输出时key使用单引号还是双引号、key不使用任何引号等等
QuoteFieldNames===========输出key时是否使用双引号,默认为true
WriteMapNullValue=========是否输出值为null的字段,默认为false
WriteNullNumberAsZero=====数值字段如果为null,输出为0,而非null
WriteNullListAsEmpty======List字段如果为null,输出为[],而非null
WriteNullStringAsEmpty====字符类型字段如果为null,输出为"",而非null
WriteNullBooleanAsFalse==Boolean字段如果为null,输出为false,而非null
6)通常在网上搜到的fastjson和springMVC整合的例子中都像下面注释的代码那样给了两个属性WriteMapNullValue和QuoteFieldNames
这就表示为json解析器设置QuoteFieldNames和WriteMapNullValue的值为true,即输出时key使用双引号,同时也输出值为null的字段
7)输出时某字段为String类型,且值为null,此时若需要其输出,且输出值为空字符串,则需同时赋值WriteMapNullValue和WriteNullStringAsEmpty
经测试,若只赋值WriteNullStringAsEmpty,则不会输出该字段..加上WriteMapNullValue属性后,便输出了,且输出值不是null,而是预期的空字符串
-->
<!--
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<bean class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter">
<property name="supportedMediaTypes">
<list>
<value>text/html;charset=UTF-8</value>
<value>application/json</value>
</list>
</property>
<property name="serializerFeature">
<array>
<value>QuoteFieldNames</value>
<value>WriteMapNullValue</value>
</array>
</property>
</bean>
</list>
</property>
</bean>
-->
<!--
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
<property name="supportedMediaTypes" value="text/html;charset=UTF-8"/>
</bean>
</list>
</property>
</bean>
-->
4.applicationContext.xml配置
<context:annotation-config/>