anchor.diff:          HttpSession httpSession = request.getSession();
           Serializable sid = (Serializable) httpSession.getAttribute("sid");
           Principal principal;
  +        List<String> expands=new ArrayList<String>();
  +        expands.add("empresa");
  +        expands.add("centro");
  +        expands.add("titulado");
           if (sid == null) {
               principal = null;
           } else {
  
positive.code: <%@ page language="java" contentType="text/javascript; charset=UTF-8" pageEncoding="UTF-8"%>
  <%@page import="es.logongas.ix3.core.hibernate.HibernateUtil"%>
  <%@page import="es.logongas.ix3.security.authentication.AuthenticationManager"%>
  
negative.code:         
          if (principal != null) {
              JsonWriter jsonWriter = jsonFactory.getJsonWriter(Principal.class);
              jsonUser = jsonWriter.toJson(principal,expands);
          } else {
              jsonUser = "null";
          }
  