filter完成一致验证

filter>
  <filter-name>AuthFilter</filter-name>
  <filter-class>com.hugui.drp.util.filter.AuthFilter</filter-class>
 </filter>
 <filter-mapping>
  <filter-name>AuthFilter</filter-name>
  <url-pattern>*.jsp</url-pattern>
 </filter-mapping>
 
 <filter-mapping>
  <filter-name>AuthFilter</filter-name>
  <url-pattern>/servlet/*</url-pattern>
 </filter-mapping>

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 AuthFilter implements Filter {

 public void destroy() {
  // TODO Auto-generated method stub

 }

 public void doFilter(ServletRequest request, ServletResponse response,
   FilterChain chain) throws IOException, ServletException {
  HttpServletRequest req = (HttpServletRequest)request;
  HttpServletResponse  resp = (HttpServletResponse)response;
  System.out.println(req.getRequestURI());
  System.out.println(req.getRequestURL());
  String requestURI = req.getRequestURI().substring(req.getRequestURI().indexOf("/", 1), req.getRequestURI().length());
  if(!"/login.jsp".equals(requestURI)){
   //如果session没登录
   HttpSession session = req.getSession(false);
   if(session == null || session.getAttribute("user_info") == null){
    resp.sendRedirect(req.getContextPath() + "/login.jsp");
    return ;
   }
  }
  //继续访问其他资源
  chain.doFilter(req, resp);
  

 }

 public void init(FilterConfig filterConfig) throws ServletException {
  // TODO Auto-generated method stub

 }

}