使用过滤器过滤用户登陆代码

package com.wap3.navigater.util;

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.HttpServletResponse;
import javax.servlet.http.HttpSession;

public class UserLoginFilter implements Filter {

public void destroy() {
// TODO Auto-generated method stub

}

public void doFilter(ServletRequest request, ServletResponse response,
FilterChain filterChain) throws IOException, ServletException {
HttpServletRequest httpRequest = (HttpServletRequest)request;
HttpServletResponse httpResponse = (HttpServletResponse)response;
HttpSession session = httpRequest.getSession();
String path = httpRequest.getRequestURL().toString();
if((!path.endsWith(".jsp") && !path.endsWith(".java")) || (path.endsWith("login.jsp")||path.endsWith("loginCheck.jsp"))){
filterChain.doFilter(request, response);
return;
}
if(session.getAttribute("administrator") == null){
httpResponse.sendRedirect("login.jsp");
return;
}
filterChain.doFilter(request, response);
}

public void init(FilterConfig arg0) throws ServletException {
// TODO Auto-generated method stub

}

}