【JavaEE企业应用实战学习记录】authorityFilter

1 package sanglp.servlet;
2
3 import javax.servlet.*;
4 import javax.servlet.annotation.WebFilter;
5 import javax.servlet.annotation.WebInitParam;
6 import javax.servlet.http.HttpServletRequest;
7 import javax.servlet.http.HttpSession;
8 import java.io.IOException;
9
10
11
12 /**
13  * Created by Administrator on 2016/10/5.
14  */
15 @WebFilter(filterName = "authority",urlPatterns = {"/*"},initParams = {
16     @WebInitParam(name = "encoding",value = "UTF-8"),
17         @WebInitParam(name = "loginPage",value = "/chap2/login.jsp"),
18         @WebInitParam(name = "proLogin", value="/chap2/proLogin.jsp")
19 })
20 public class AuthorityFilter implements Filter {
21     //用于访问Filter的配置信息
22     private FilterConfig config;
23
24     @Override
25     public void init(FilterConfig filterConfig) throws ServletException {
26         this.config=filterConfig;
27     }
28
29     @Override
30     public void destroy() {
31         this.config=null;
32     }
33
34     @Override
35     public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
36         //获取该Filter的配置参数
37         String encoding=config.getInitParameter("encoding");
38         String loginPage=config.getInitParameter("loginPage");
39         String proLogin=config.getInitParameter("proLogin");
40         //设置request编码用的字符集
41         servletRequest.setCharacterEncoding(encoding);
42         HttpServletRequest hreq=(HttpServletRequest) servletRequest;
43         HttpSession session=hreq.getSession(true);
44         //获取客户请求的页面
45         String requestPath=hreq.getServletPath();
46         //如果session范围的user为null即表明没有邓丽。且用户请求的既不是登录页面，也不是处理登录的页面
47         if(session.getAttribute("user")==null&&!requestPath.endsWith(loginPage)&&!requestPath.endsWith(proLogin)){
48             servletRequest.setAttribute("tip","您还没有登录");
49             servletRequest.getRequestDispatcher(loginPage).forward(servletRequest,servletResponse);
50
51         }else{
52             //履行请求
53             filterChain.doFilter(servletRequest,servletResponse);
54         }
55     }
56 }