JSP/Servlet设置编码格式的问题

在Java Web项目中总会遇到编码格式问题，在JSP/Servlet与浏览器传输数据时，处理编码格式的方式通常是设置request对象和response对象的编码格式。然而，一个项目中有很多个JSP/Servlet，在每个JSP/Servlet中分别对request对象和response对象进行编码格式的设置是一件非常麻烦的事情，于是我们想能不能把对于request对象和response对象编码格式的设置统一起来做。用过滤器解决统一设置编码格式的问题    定义一个过滤器类CharacterEncodingFilter        package org.zeroup.filter;         import java.io.IOException;    import javax.servlet.Filter;    import javax.servlet.FilterChain;    import javax.servlet.FilterConfig;    import javax.servlet.ServletException;    import javax.servlet.ServletRequest;    import javax.servlet.ServletResponse;         public class CharacterEncodingFilter implements Filter {             protected FilterConfig filterConfig = null;        protected String encoding = "";             public void init(FilterConfig filterConfig) throws ServletException {            this.filterConfig = filterConfig;            this.encoding = filterConfig.getInitParameter("encoding");        }        public void doFilter(ServletRequest request, ServletResponse response,                FilterChain chain) throws IOException, ServletException {                 request.setCharacterEncoding(this.encoding);            response.setCharacterEncoding(this.encoding);            response.setContentType("text/html;charset="+this.encoding);                 chain.doFilter(request, response);        }        public void destroy() {            this.encoding = null;            this.filterConfig = null;        }    }    在项目配置文件web.xml中添加过滤器的配置信息            <filter>            <description>CharacterEncodingFilter</description>            <display-name>CharacterEncodingFilter</display-name>            <filter-name>CharacterEncodingFilter</filter-name>            <filter-class>                org.zeroup.filter.CharacterEncodingFilter            </filter-class>            <init-param>    <param-name>encoding</param-name>    <param-value>utf-8</param-value>            </init-param>        </filter>             <filter-mapping>            <filter-name>CharacterEncodingFilter</filter-name>            <url-pattern>/*</url-pattern>        </filter-mapping>此例将当前项目中所有request和response对象字符编码格式全部设置为utf-8，同时浏览器端读取和发送数据的编码格式也自动设定为utf-8。