过滤器链实现中文转码和文字屏蔽功能(3)

    </filter-mapping> 
     
 
    <servlet> 
        <servlet-name>MessageServlet</servlet-name> 
        <servlet-class>com.mars.servlet.MessageServlet</servlet-class> 
    </servlet> 
    <servlet-mapping> 
        <servlet-name>MessageServlet</servlet-name> 
        <url-pattern>/MessageServlet</url-pattern> 
    </servlet-mapping> 
     
    <welcome-file-list> 
        <welcome-file>submit.jsp</welcome-file> 
    </welcome-file-list> 
</web-app> 

[java]
package com.mars.filter; 
 
import java.io.IOException; 
import java.io.UnsupportedEncodingException; 
 
import javax.servlet.Filter; 
import javax.servlet.FilterChain; 
import javax.servlet.FilterConfig; 
import javax.servlet.ServletException; 
import javax.servlet.ServletRequest; 
import javax.servlet.ServletResponse; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletRequestWrapper; 
import javax.servlet.http.HttpServletResponse; 
 
public class CharacterFilter implements Filter { 
    public void init(FilterConfig arg0) throws ServletException { 
        System.out.println("调用init"); 
    } 
 
    public void destroy() { 
        System.out.println("调用destroy"); 
    } 
 
    // 解决post方式的乱码问题 
    public void doFilter(ServletRequest req, ServletResponse resp, 
            FilterChain chain) throws IOException, ServletException { 
 
        HttpServletRequest request = (HttpServletRequest) req; 
        HttpServletResponse response = (HttpServletResponse) resp; 
        request.setCharacterEncoding("GBK"); 
        response.setCharacterEncoding("GBK"); 
        response.setContentType("text/html;charset=GBK"); 
        chain.doFilter(request, response);