package cn.itcast.elec.util;
import java.io.IOException;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.List;
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.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.itcast.elec.domain.ElecUser;
public class SystemFilter implements Filter {
//存放需要放行的连接
List<String> list = new ArrayList<String>();
public void init(FilterConfig config) throws ServletException {
//定义系统在没有Session之前哪些连接需要放行
list.add("/index.jsp");
list.add("/image.jsp");
list.add("/system/elecMenuAction_home.do");
list.add("/error.jsp");
list.add("/system/elecMenuAction_logout.do");
}
public void doFilter(ServletRequest req, ServletResponse res,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
//获取访问的路径path
String path = request.getServletPath();
//当访问的路径path包含index.jsp的时候，此时从Cookie中获取登录名和密码，并在index.jsp中进行显示，处理记住我的功能
this.forwardIndexPage(path,request);
//使用Session控制系统的粗颗粒度权限控制
//如果访问的路径path包含在定义的连接内，此时都需要放行
if(list.contains(path)){
chain.doFilter(request, response);
return;
}
//从Session中获取当前用户的信息
ElecUser elecUser = (ElecUser) request.getSession().getAttribute("globle_user");
if(elecUser!=null){
//使用页面地址栏输入访问的url，实现细颗粒度权限控制
//从Session中获取当前登录人所能够操作的url
List<String> urlList = (List<String>) request.getSession().getAttribute("globle_url");
if(urlList.contains(path)){
chain.doFilter(request, response);
return;
}
}
//重定向到登录页面
//response.sendRedirect(request.getContextPath()+"/");
//跳转到错误页面，5秒钟后跳转到登录页面（友好）
response.sendRedirect(request.getContextPath()+"/error.jsp");
}
public void destroy() {
}
/**当访问的路径path包含index.jsp的时候，此时从Cookie中获取登录名和密码，并在index.jsp中进行显示，处理记住我的功能*/
private void forwardIndexPage(String path, HttpServletRequest request) {
if(path.contains("/index.jsp")){
String name = "";
String password = "";
String checked = "";
Cookie [] cookies = request.getCookies();
if(cookies!=null && cookies.length>0){
for(int i=0;i<cookies.length;i++){
Cookie cookie = cookies[i];
if(cookie!=null && cookie.getName().equals("name")){
name = cookie.getValue();
//如果name中存在中文的话，对值进行解码
try {
name = URLDecoder.decode(name, "UTF-8");
} catch (Exception e) {
e.printStackTrace();
}
checked = "checked";
}
else if(cookie!=null && cookie.getName().equals("password")){
password = cookie.getValue();
}
}
}
//将3个值放置到request中
request.setAttribute("name", name);
request.setAttribute("password", password);
request.setAttribute("checked", checked);
}
}
}