HttpServletRequest request=(HttpServletRequest) ServiceContext.getContextRequest();
HttpSession session=request.getSession();
if(session.getAttribute("user")==null){
System.out.println("没有登录，拦截");
session.setAttribute("user", "guest");
InteractionException i=new InteractionException("没有登录",99999);
throw i;
}else{
return invocation.proceed();
}
}