springmvc之获取参数的方法(必看)

<servlet>  <servlet-name>springDispatcherServlet</servlet-name>  <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  <init-param>   <param-name>contextConfigLocation</param-name>   <param-value>classpath:springmvc.xml</param-value>  </init-param>  <load-on-startup>1</load-on-startup> </servlet>  <!-- Map all requests to the DispatcherServlet for handling --> <servlet-mapping>  <servlet-name>springDispatcherServlet</servlet-name>  <url-pattern>/</url-pattern> </servlet-mapping>    <!--字符编码的filter一定要放在最前面 -->  <filter>   <filter-name>CharacterEncodingFilter</filter-name>  <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>  <!-- 配置encoding，告诉我们指定的编码格式 -->  <init-param>   <param-name>encoding</param-name>   <param-value>utf-8</param-value>  </init-param>  <!-- 解决响应乱码 -->  <init-param>   <param-name>forceEncoding</param-name>   <param-value>true</param-value>  </init-param>  </filter>  <filter-mapping>   <filter-name>CharacterEncodingFilter</filter-name>   <url-pattern>/</url-pattern>  </filter-mapping>   <!-- 支持rest的filter -->  <filter>   <filter-name>HiddenHttpMethodFilter</filter-name>  <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>  </filter>   <filter-mapping>   <filter-name>HiddenHttpMethodFilter</filter-name>   <url-pattern>/*</url-pattern>  </filter-mapping>