adminfilter.java

一个用户管理系统的例子,作的很好,有前端,有后台,增加,删除,修改,查找都可以实现

package com.allanlxf.ums.web;

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;

import com.allanlxf.ums.entity.Administrator;
import com.allanlxf.ums.entity.User;

public class AdminFilter implements Filter
{
    private FilterConfig config;

    public void init(FilterConfig config) throws ServletException
    {
        this.config = config;
    }

    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException
    {
        doFilter((HttpServletRequest) request, (HttpServletResponse) response,
                chain);
    }

    public void doFilter(HttpServletRequest request,
            HttpServletResponse response, FilterChain chain)
            throws IOException, ServletException
    {
        HttpSession session = request.getSession();
        User user = (User) session.getAttribute("user");
        if (user != null && user instanceof Administrator)
        {
            chain.doFilter(request, response);
        }else
        {
            response.sendRedirect(request.getContextPath() + "/tologin.do");
        }
    }

    public void destroy()
    {
    }
}