我有一个Spring-MVC应用程序(即我使用的是Spring的调度程序servlet).我也使用Spring Security来验证用户身份.因为我使用Spring的调度程序servlet,所以我不必声明

  @H_502_8@
在我的web.xml中,以便能够使用RequestContextHolder(如果我正确理解文档).
我的问题涉及我的接口org.springframework.security.web.authentication.AuthenticationSuccessHandler的实现：

public class AuthenticationSuccessHandlerImpl implements AuthenticationSuccessHandler {

    @Override
    public void onAuthenticationSuccess(HttpServletRequest request,HttpServletResponse response,Authentication authentication) throws ServletException,IOException {

        int timeout = 60*60;

        //does work
        request.getSession().setMaxInactiveInterval(timeout); //60 minutes
        System.out.println("Session timeout of user: " + authentication.getName() + " has been set to: " + timeout + " seconds.");

        /*
        //does not work
        session().setMaxInactiveInterval(timeout); //60 minutes
        System.out.println("Session timeout of user: " + request.getUserPrincipal().getName() + " has been set to: " + timeout + " seconds.");
        */

        //now restore the default work flow (SavedRequestAwareAuthenticationSuccessHandler is the default AuthenticationSuccessHandler that Spring uses,// see: http://static.springsource.org/spring-security/site/docs/3.0.x/reference/core-web-filters.html#form-login-flow-handling )
        (new SavedRequestAwareAuthenticationSuccessHandler()).onAuthenticationSuccess(request,response,authentication);
    }

    public static HttpSession session() {
        ServletRequestAttributes attr = (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
        return attr.getRequest().getSession(true); // true == allow create
    }
}
@H_502_8@
你能解释为什么在上面提到的代码中,RequestContextHolder.currentRequestAttributes()和HttpServletRequest.getUserPrincipal()不起作用(它们在Controller内部工作)？
谢谢！