@Override
    public String execute() throws Exception {
        try {
            Map session = ActionContext.getContext().getSession();
            session.put("User", null);
            session.clear();
            myDao.getDbsession().close();
            addActionMessage("Successfully Logged Out.");
            return "success";
        } catch (HibernateException e) {
            addActionError("Server  Error Please Try Again ");
            e.printStackTrace();
            return "error";
        } catch (NullPointerException ne) {

            addActionError("Server  Error Please Try Again ");
            ne.printStackTrace();
            return "error";
        } catch (Exception e) {

            addActionError("Server  Error Please Try Again ");
            e.printStackTrace();
            return "error";
        }
    }