万能编码解码器

编程技术  /  houtizong 发布于 3年前   62

/**
 * $Id: EncodingFilter.java,v 1.3 2008/08/20 20:02:05 cvs Exp $
 */
package com.cy.tiles.struts;

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;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

public class EncodingFilter implements Filter
{
 protected String    encoding   = null;
  class Request extends HttpServletRequestWrapper
     {

         public Request(HttpServletRequest request) {
          
             super(request);
            
         }

         /**
          * 转换由表单读取的数据的内码.
          * 从 ISO 字符转到 GBK.
          */
         public String toChi(String input) {
             try {
              // System.out.println(input);
               byte[] bytes = input.getBytes("ISO8859-1");
               return new String(bytes, "UTF-8");
             }
             catch (Exception ex) {
             }
             return null;
         }

         /**
          * Return the HttpServletRequest holded by this object.
          */
         private HttpServletRequest getHttpServletRequest()
         {
             return (HttpServletRequest)super.getRequest();
         }

         /**
          * 读取参数 -- 修正了中文问题.
          */
         public String getParameter(String name)
         {
             return toChi(getHttpServletRequest().getParameter(name));
         }

         /**
          * 读取参数列表 - 修正了中文问题.
          */
         public String[] getParameterValues(String name)
         {
          System.out.println(":");
               String values[] = getHttpServletRequest().getParameterValues(name);
               if(values!=null)
               values= values.clone();
               if (values != null) {
                 for (int i = 0; i < values.length; i++) {
                   values[i] = toChi(values[i]);
                 }
               }
               return values==null?null:values;
         }
     }

 public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException
 {
  HttpServletRequest httpreq = (HttpServletRequest)request;
   
   
   if(httpreq.getMethod()=="POST") {
    request.setCharacterEncoding(encoding);
         } else {
             request = new Request(httpreq);
         }
   
   chain.doFilter(request,response);
 }

 public void init(FilterConfig filterConfig) throws ServletException
 {
  this.encoding = filterConfig.getInitParameter("encoding");
  
  
  
  if (null == encoding){
   throw new IllegalArgumentException("Please add encoding parameter");
   
  }

 }

 public void destroy() {
  
  
 }

}

 

<filter>
<filter-name>login</filter-name>
<filter-class>cn.mldn.lxh.filter.LoginFilter</filter-class>
<init-param>
<param-name>par</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>login</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>