SpringMVC返回Json失败，请检查是否配置了Jackson

Posted 2020-10-01

背景

需要一套干净的Spring+Spring MVC+Mybatis框架，框架写到返回Json的环节报错了。

问题

无法Json，报406

解决

需要配置Json工具包，这里用Jackson

Maven Jackson

        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.6.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.6.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.6.0</version>
        </dependency>

工程环境SpringMvc 4.x，不兼容Jackson2.9最新版。这里特应用2.6版本

Spring Mvc配置

    <!--Begin:使用Jackson 2.x的配置，需要导入的jar包：jackson-core-xxx.jar、jackson-annotations-xxx.jar、jackson-databind-xxx.jar-->
    <!--通过处理器映射DefaultAnnotationHandlerMapping来开启支持@Controller注解-->
    <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping" />
    <!--通过处理器适配器AnnotationMethodHandlerAdapter来开启支持@RequestMapping注解-->
    <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
        <property name="messageConverters">
            <list>
                <!-- 设置返回字符串编码 -->
                <bean class="org.springframework.http.converter.StringHttpMessageConverter">
                    <property name = "supportedMediaTypes">
                        <list>
                            <value>text/html;charset=UTF-8</value>
                            <value>application/json;charset=UTF-8</value>
                        </list>
                    </property>
                </bean>
                <!-- json转换器 -->
                <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
                    <property name="supportedMediaTypes">
                        <list>
                            <value>text/html;charset=UTF-8</value>
                            <value>application/json;charset=UTF-8</value>
                        </list>
                    </property>
                </bean>
            </list>
        </property>
    </bean>
    <!--End:使用Jackson 2.x的配置，需要导入的jar包：jackson-core-xxx.jar、jackson-annotations-xxx.jar、jackson-databind-xxx.jar-->

好了，重启不报错（一般就是jar宝冲突），就可以正常接收到@ResponseBody返回的Json了。

以上配置，带来好运，祝好    ！

by.沫沫金

我得纯净框架，新模块只需要一个Controller就可以，CRUD一句话全搞定。前台专注Form就行。

本文出自 “沫沫金的IT心得与技巧” 博客，请务必保留此出处http://zl0828.blog.51cto.com/2242565/1954239