SessionUtils.validSessionVerification(request, mapping);
	public ActionForward execute(		ActionMapping mapping,		ActionForm form,		HttpServletRequest request,		HttpServletResponse response)		throws Exception {		HttpSession sessao = getSession(request);		String parameter = request.getParameter("operation");		if (parameter.equals("Ver Sala")) {			return prepararVerSala(mapping, form, request, response);		}		if (parameter.equals("Editar Sala")) {			return prepararEditarSala(mapping, form, request, response);		}		if (parameter.equals("Apagar Sala")) {			return apagarSala(mapping, form, request, response);		}		return (mapping.findForward("Voltar"));	}