1、查看是否Jackson包是否存在。

需要下载maven依赖

<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.6.0</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.6.0</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.6.0</version>
</dependency>

2、如果后缀是html是不能响应json数据的。需要修改后缀名。

如果因项目部方便修改可以在web.xml中添加多个后缀

<servlet>
<servlet-name>provider</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<!-- contextConfigLocation不是必须的， 如果不配置contextConfigLocation， springmvc的配置文件默认在：WEB-INF/servlet的name+"-servlet.xml" -->
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring/springmvc.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>provider</servlet-name>
<!-- 伪静态化 -->
<url-pattern>*.html</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>provider</servlet-name>
<url-pattern>*.action</url-pattern>
</servlet-mapping>