从Spring MVC控制器的安全上下文中获取UserDetails对象

如果您已经确定用户已经登录（在您的示例中

/index.html

UserDetails userDetails = (UserDetails)SecurityContextHolder.getContext().getAuthentication().getPrincipal();

要首先检查用户是否已登录，请检查当前用户

Authentication

AnonymousAuthenticationToken

Authentication auth = SecurityContextHolder.getContext().getAuthentication();if (!(auth instanceof AnonymousAuthenticationToken)) {        // userDetails = auth.getPrincipal()}