How to edit existing record using jsp

[ghjk]

I'm new to java.I,m developing web application using jsp,struts,hibe rnet. I want to edit database record. This is my code and when I edit and save it it didn't update record but add a new one. Please help me..

        UserAdminActionForm formbean = (UserAdminActionForm) form;
        String fullname = formbean.getFullname();
        String email = formbean.getEmail();
        Session s = data.DataAccess.getDataAccess().getSession();
        Transaction tr = s.beginTransaction();

        data.UserAccount user = new data.UserAccount();
       
        user.setFullName(fullname);
        user.setEmail(email);
        s.update(user);
        tr.commit();