web.xml 字符过滤器-优快云博客

本文介绍了一个Spring框架中的字符编码过滤器，该过滤器允许开发者为请求指定字符编码，以解决浏览器通常不设置字符编码的问题。文章详细展示了如何配置web.xml中的CharacterEncodingFilter，并解释了其工作原理。

org.springframework.web.filter.CharacterEncodingFilter

web.xml文件
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
version="2.4">

    <filter>
      <filter-name>CharacterEncodingFilter</filter-name>
      <filter-class>
           org.springframework.web.filter.CharacterEncodingFilter
      </filter-class>
      init-param>
       <param-name>encoding</param-name>
       <param-value>GB2312</param-value>
      </init-param>
      <init-param>
       <param-name>forceEncoding</param-name>
       <param-value>true</param-value>
      </init-param>
     </filter>

　　<filter-mapping>
　　<filter-name>SetCharacterEncoding</filter-name>
　　<url-pattern>*.jsp</url-pattern>
　　</filter-mapping>

</web-app>

public class CharacterEncodingFilter

extends OncePerRequestFilter

Servlet 2.3/2.4 Filter that allows one to specify a character encoding for requests. This is useful because current browsers typically do not set a character encoding even if specified in the HTML page or form.

This filter can either apply its encoding if the request does not already specify an encoding, or enforce this filter's encoding in any case ("forceEncoding"="true"). In the latter case, the encoding will also be applied as default response encoding on Servlet 2.4+ containers (although this will usually be overridden by a full content type set in the view).