基于springMVC实现登录过滤器

此文章是基于　　搭建Jquery+SpringMVC+Spring+Hibernate+MySQL平台

一. 相关文件介绍

　　1. LoginFilter.java：登录过滤器，保证每次的url访问都对session进行验证

package com.ims.web;

import java.io.IOException;

import java.io.PrintWriter;

import javax.servlet.FilterChain;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import org.springframework.web.filter.OncePerRequestFilter;

import com.ims.common.ConfigHolder;

/**

 * 登陆过滤器

 */

public class LoginFilter extends OncePerRequestFilter{

    @Override

    protected void doFilterInternal(HttpServletRequest request,

            HttpServletResponse response, FilterChain filterChain)

            throws ServletException, IOException {

        // 不拦截的url

        String[] notFilter = new String[] {"/login.do","/service"};

        // 请求的url

        String url = request.getRequestURI();

        boolean doFilter = chek(notFilter, url);

        if (doFilter) {

            HttpSession session = request.getSession();

            Object obj = session.getAttribute(ConfigHolder.getValue("session.sys.user"));

            if (null == obj) {

                // 如果session中不存在登录者实体，则弹出框提示重新登录

                PrintWriter out = response.getWriter();

                String loginPage = request.getContextPath() + "/login.do";

                StringBuilder builder = new StringBuilder();

                builder.append("<script type=\"text/javascript\">");

                builder.append("window.top.location.href='");

                builder.append(loginPage);

                builder.append("';");

                builder.append("</script>");

                out.print(builder.toString());

            } else {

                filterChain.doFilter(request, response);

            }

        } else {

            filterChain.doFilter(request, response);

        }

    }

    /**

     * 检查是否拦截

     * @param notFilter 不拦截的url

     * @param url 请求的url

     * @return false：不拦截  true：拦截

     */

    public boolean chek(String[] notFilter, String url) {

        // 图片、脚本、css、页面不进行拦截

        if (url.endsWith(".css") || url.endsWith(".js")

            || url.endsWith(".png") || url.endsWith(".jpg")

            || url.endsWith(".gif") || url.endsWith(".jsp")

            || url.endsWith(".html")) {

            return false;

        }

        // 含有notFilter中的任何一个则不进行拦截

        for (String s : notFilter) {

            if (url.indexOf(s) != -1) {

                return false;

            }

        }

        return true;

    }

}

　　

　　2. web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:web="http://xmlns.jcp.org/xml/ns/javaee"

    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_4.xsd

        http://xmlns.jcp.org/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"

    version="2.4">

  <filter>

    <filter-name>loginFilter</filter-name>

    <filter-class>com.ims.web.LoginFilter</filter-class>

  </filter>

  <filter-mapping>

    <filter-name>loginFilter</filter-name>

    <url-pattern>/*</url-pattern>

  </filter-mapping>

</web-app>