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

	}

}