使用messageConverters

<bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter" >  
    <property name="messageConverters">  
        <list>  
            <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" />  
            <bean class="org.springframework.http.converter.StringHttpMessageConverter">  
                <property name="supportedMediaTypes">  
                    <list>  
                        <value>text/plain;charset=utf-8</value>  
                        <value>text/html;charset=UTF-8</value>  
                    </list>  
                </property>  
            </bean>  
        </list>  
    </property>  </bean>

在springmvc的配置文件中，将消息转换器的bean放在 <mvc:annotation-driven/> 的前面（上面），否则配置不会生效

需要jackson的依赖

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.8.8</version>
        </dependency>

如果上面这个不够，那就再追加或者替换为：

<dependency>  
    <groupId>org.codehaus.jackson</groupId>  
    <artifactId>jackson-mapper-asl</artifactId>  
    <version>1.9.13</version>  </dependency>  <dependency>  
    <groupId>org.codehaus.jackson</groupId>  
    <artifactId>jackson-core-asl</artifactId>  
    <version>1.9.13</version>  </dependency>

原文出处： https://www.cnblogs.com/kinome/p/9626375.html