登陸攔截

package com.xasxt.filter;


import java.io.IOException;
import java.util.HashSet;
import java.util.Set;


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 LoginFilter implements Filter {
static Set<String> whiteList  = new HashSet<String>();

static {
whiteList.add("login.jsp");
whiteList.add("LoginServlet");
whiteList.add("register.jsp");
whiteList.add("RegisterServlet");
}
public void destroy() {

}


public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("LoginFilter.doFilter()");

HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse res = (HttpServletResponse) response;
HttpSession session = req.getSession();
System.out.println(req.getRequestURI());
String pageName = req.getRequestURI().substring(req.getRequestURI().lastIndexOf("/")+1);
System.out.println(pageName);
if (whiteList.contains(pageName)||req.getRequestURI().endsWith("jpg")) {
//放行
chain.doFilter(request, response);
}else if(session.getAttribute("loginAccount")==null){
res.sendRedirect("login.jsp");
}else {
chain.doFilter(request, response);
}
}
public void init(FilterConfig arg0) throws ServletException {
}


}