package com.test.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 EncodeFilter implements Filter {  

private String encode;      

public EncodeFilter() {     }

 public void destroy() {  }

 public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException{   response.setCharacterEncoding(encode);   

　　chain.doFilter(request, response);  }

 public void init(FilterConfig fConfig) throws ServletException {   

encode = fConfig.getInitParameter("encode");  }

}

web.xml

<filter>
    <display-name>EncodeFilter</display-name>
    <filter-name>EncodeFilter</filter-name>
    <filter-class>com.test.filter.EncodeFilter</filter-class>
    <init-param>
      <param-name>encode</param-name>
      <param-value>utf-8</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>EncodeFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

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