自动登录的逻辑设计 - 黑马程序员技术交流社区

//过滤器功能
public class UserLoginFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
System.out.println("过滤启动");
}
@Override
public void doFilter(ServletRequest req, ServletResponse res,
FilterChain chain) throws IOException, ServletException {
//将参数转换为和协议有关
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
//(1)如果请求登录界面，则放行
if("/HE06/index.jsp".equals(request.getServletContext())){
chain.doFilter(request, response);
return;
}
//(2)如果已登录，则放行
if(request.getSession().getAttribute("user") != null){
chain.doFilter(request, response);
return;
}
//下面是未登录，则根据携带cookie与否，和是否正确来判断
Cookie tempCookie = null;
//判断是否有cookie
Cookie[] cookie = request.getCookies();
if(cookie != null){
for (Cookie ck : cookie) {
if("autoinfo".equals(ck.getName())){
tempCookie = ck;
}
}
}
/*cookie是否正确
if(tempCookie != null){
User user = new User(tempCookie.getValue().split("#")[0],
tempCookie.getValue().split("#")[1]);
user = new UserService().find(user);
//不正确，则删除cookie信息
if(user == null){
tempCookie.setMaxAge(0);
tempCookie.setPath("/");
response.addCookie(tempCookie);
chain.doFilter(request, response);
return;
}
//如果信息正确，则记录登录,并放行
request.getSession().setAttribute("user", user);
}
chain.doFilter(request, response);
*/
if(tempCookie == null){
chain.doFilter(request, response);
return;
}
String[] userStr = tempCookie.getValue().split("#");
User user = new User(userStr[0], userStr[1]);
user = new UserService().find(user);
if(user == null){
tempCookie.setMaxAge(0);
tempCookie.setPath("/");
response.addCookie(tempCookie);
chain.doFilter(request, response);
return;
}
request.getSession().setAttribute("user", user);//记录登录
chain.doFilter(request, response);
}
@Override
public void destroy() {
System.out.println("过滤销毁");
}
}
------------------------------------------------------------------------
//登录处理功能
public class UserLoginServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
/**
* 从请求中获取相应参数，封装后，传递给服务器查找
* 如果可以查找到，即登录成功
* 然后判断用户是否勾选了自动登录
*/
//封装并查询
User user = new User(request.getParameter("name"),request.getParameter("password"));
user = new UserService().find(user);
//根据查询结果进行操作
if(user != null){
//设置cookie信息
if(request.getParameter("auto") != null){
Cookie cookie = new Cookie("autoinfo",user.getName()+"#"+user.getPassword());
cookie.setMaxAge(60*60);
cookie.setPath("/");
response.addCookie(cookie);
}
//记录登录状态，并重定向到成功界面
request.getSession().setAttribute("user", user);
response.sendRedirect(request.getContextPath()+"/suc.jsp");
}else{
//不成功则给提示
request.setAttribute("msg", "用户名和密码不一致");
request.getRequestDispatcher("/index.jsp").forward(request, response);
}
}
}

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