Spring配置文件添加
1、<mvc:annotation-driven/>
2、<context:component-scan base-package="com.cn.hnust.controller" />
pom文件依赖
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>1.9.13</version>
</dependency>
