setcharacterencodingfilter.java

一个信息发布系统 基于jsp+servlet+tomcat 用户分管理员跟普通用户 普通用户有发布信息 查询信息 修改信息 回复信息 管理员拥有普通用户的功能 此外还具有删除信息 管理信息的回复的功能

package control;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.UnavailableException;
public class SetCharacterEncodingFilter implements Filter {

         protected String encoding = null;
         protected FilterConfig filterConfig = null;
         protected boolean ignore = true;
         public void destroy() {
             this.encoding = null;
             this.filterConfig = null;
         }  
          public void doFilter(ServletRequest request, ServletResponse response,FilterChain chain)
          throws IOException, ServletException   {
             if (ignore || (request.getCharacterEncoding() == null)) {
                 String encoding = selectEncoding(request);
                 if (encoding != null)
                     request.setCharacterEncoding(encoding);
             }
// Pass control on to the next filter
             chain.doFilter(request, response);
         }

        public void init(FilterConfig filterConfig) throws ServletException {
this.filterConfig = filterConfig;
             this.encoding = filterConfig.getInitParameter("encoding");
             String value = filterConfig.getInitParameter("ignore");
             if (value == null)
                 this.ignore = true;
             else if (value.equalsIgnoreCase("true"))
                 this.ignore = true;
             else if (value.equalsIgnoreCase("yes"))
                 this.ignore = true;
             else
                 this.ignore = false;
         }
           protected String selectEncoding(ServletRequest request) {
             return (this.encoding);
         }
}