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处理json和表单参数的JavaSpringMVC方法

我想要在single spring mvc方法中处理内容类型application/x-www-form-urlencoded和application/json

我在rest服务中有一个要求,即接受作为表单参数或json的输入。我可以通过编写两种方法来实现这一点。无论是formparams还是json,响应都将始终是json

@RequestMapping (method = RequestMethod.POST, produces = {"application/json"},
        consumes = {"application/x-www-form-urlencoded"})
public @ResponseBody Book createBook(Book book)
        throws Exception {
    return book;
}

@RequestMapping (method = RequestMethod.POST, produces = {"application/json"},
        consumes = {"application/json"})
public @ResponseBody Book createBookJSON(@RequestBody Book book)
        throws Exception {
    return book;
} 

有没有可能将这两种方法结合在一起并使其发挥作用?任何帮助都将不胜感激

编辑

我已经实现了相同的功能,下面给出了我的控制器和配置,但是当我发送json请求时,我会得到空值作为响应

当我发送表单参数时,它工作正常。帮我找出问题所在

控制器方法

 @RequestMapping (method = RequestMethod.POST, produces = {"application/json", "application/xml"}, consumes = {"application/x-www-form-urlencoded", "application/json"})                   
    public @ResponseBody Book createBook(Book book)
            throws Exception {
        return book;
    }

servlet上下文

<mvc:view-controller path="/" view-name="index"/>

<context:annotation-config />

<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"/>

<bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"/>

<bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
    <property name="order" value="1" />
    <property name="mediaTypes">
        <map>
            <entry key="xml" value="application/xml" />
            <entry key="json" value="application/json" />
        </map>
    </property>
    <property name="defaultViews">
        <list>
            <!-- JSON View -->
            <bean class="org.springframework.web.servlet.view.json.MappingJacksonJsonView" />

            <!-- JAXB XML View -->
            <bean class="org.springframework.web.servlet.view.xml.MarshallingView">
                <constructor-arg>
                    <ref bean="jaxb2Marshaller" />
                </constructor-arg>
            </bean>

        </list>
    </property>
    <property name="ignoreAcceptHeader" value="true" />
</bean>

<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" >
    <property name="order" value="1" />
    <property name="messageConverters">
        <list>
            <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" >
                <property name="supportedMediaTypes" value="application/json"/>
            </bean>

            <bean id="marshallingHttpMessageConverter" class="org.springframework.http.converter.xml.MarshallingHttpMessageConverter">
                <property name="marshaller" ref="jaxb2Marshaller" />
                <property name="unmarshaller" ref="jaxb2Marshaller" />
                <property name="supportedMediaTypes" value="application/xml"/>
            </bean>

            <bean class = "org.springframework.http.converter.FormHttpMessageConverter">
                <property name="supportedMediaTypes" value = "application/x-www-form-urlencoded" />
            </bean>

            <bean class = "org.springframework.http.converter.StringHttpMessageConverter">
                <property name="supportedMediaTypes" value = "text/plain;charset=UTF-8" />
            </bean>
        </list>
    </property>
</bean>

<bean id="jaxb2Marshaller" class="org.springframework.oxm.jaxb.Jaxb2Marshaller" >
    <property name="classesToBeBound">
        <list>
            <value>com.lt.domain.Book</value>
        </list>
    </property>
</bean>

<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="order" value="2" />
    <property name="prefix" value="/WEB-INF/views/"/>
    <property name="suffix" value=".jsp"/>
</bean>

共 (2) 个答案

  1. # 1 楼答案

    如果您想让spring自动从JSON转换为您的对象,您必须使用@RequestBody。如果您不使用它,那么这些值将不会被绑定,并且所有参数都是空的,正如您在发送JSON时所描述的那样

    如果您使用@RequestBody:在幕后,转换是使用MessageConverter完成的,如spring文档中所述:http://static.springsource.org/spring/docs/3.1.x/spring-framework-reference/html/mvc.html#mvc-ann-requestbody

    您正在正确配置MappingJacksonHttpMessageConverter,它将JSON转换为您的对象

    缺少的是从表单数据到对象的转换: 您注册了一个FormHttpMessageConverter,但根据文档,这并不是您期望它做的。它使用x-www-form-urlencode将请求转换为MultiValueMap<String, String>,而不是转换为自定义对象

    我目前的理解是,您必须编写类似于MappingJacksonHttpMessageConverter的东西,但只能处理表单数据

  2. # 2 楼答案

    @RequestMapping (method = RequestMethod.POST)
    public Book createBook(Book book)
            throws Exception {
        return book;
    }
    

    consumes获取一个字符串数组,该数组包含它可以使用的任何内容,Springbean绑定应该负责其余部分。问题可能是您没有正确设置bean绑定以便自动整理和取消整理json。使用@RequestBody和@RepsonseBody并不是imho的最佳选择

    确保jackson已添加到您的依赖项中

    <dependency>
    <groupId>org.codehaus.jackson</groupId>
    <artifactId>jackson-mapper-asl</artifactId>
    <version>latest</version>
    </dependency>
    

    并使用ContentNegotingViewResolver

    <bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
        <property name="mediaTypes">
            <map>
                <entry key="htm" value="text/htm"/>
                <entry key="html" value="text/html"/>
                <entry key="json" value="application/json"/>
            </map>
        </property>
        <property name="viewResolvers">
            <list>
                <bean class="org.springframework.web.servlet.view.BeanNameViewResolver"/>
                <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
                    <property name="prefix" value="/WEB-INF/jsp/"/>
                    <property name="suffix" value=".jsp"/>
                </bean>
            </list>
        </property>
    
        <property name="defaultViews">
            <list>
                <bean class="org.springframework.web.servlet.view.json.MappingJacksonJsonView"/>
    
            </list>
        </property>
    </bean>
    

    确保在客户端应用程序中将accept标头设置为所需的值。 您还应该能够删除requestmethod注释中的所有生产和消费数据