public ActionForward editPhdCandidacyPeriod(
      ActionMapping mapping,
      ActionForm form,
      HttpServletRequest request,
      HttpServletResponse response) {
    PhdCandidacyPeriod phdCandidacyPeriod = readPhdCandidacyPeriod(request);
    PhdCandidacyPeriodBean bean = readPhdCandidacyPeriodBean();

    try {
      phdCandidacyPeriod.edit(bean.getStart(), bean.getEnd());
    } catch (DomainException e) {
      addActionMessage("error", request, e.getKey(), e.getArgs());
      return editPhdCandidacyPeriodInvalid(mapping, form, request, response);
    }

    return list(mapping, form, request, response);
  }
  public ActionForward list(
      ActionMapping mapping,
      ActionForm form,
      HttpServletRequest request,
      HttpServletResponse response) {
    request.setAttribute("phdCandidacyPeriods", PhdCandidacyPeriod.readPhdCandidacyPeriods());

    return mapping.findForward("list");
  }