OrganizationalStructureTreeProducer producer = new OrganizationalStructureTreeProducer(request .getContextPath(), "/manager/announcements/manageUnitAnnouncementBoard.do?method=prepareCreateBoard");  request.setAttribute("tree", producer.getUnits());
request.setAttribute("initialUnit", UnitUtils.readInstitutionUnit());
    public ActionForward showTree(ActionMapping mapping, ActionForm actionForm,            HttpServletRequest request, HttpServletResponse response) throws Exception {        OrganizationalStructureTreeProducer producer = new OrganizationalStructureTreeProducer(request                .getContextPath(),                "/manager/announcements/manageUnitAnnouncementBoard.do?method=prepareCreateBoard");        request.setAttribute("tree", producer.getUnits());        return mapping.findForward("chooseUnit");    }