public List<Transition> getTransitionsByStateAndSymbol(String state, String symbol) throws Exception{
        List<Transition> result = new ArrayList<Transition>();
        for(Transition tran: transitions){
            if(tran.matchByStateAndSymbol(state, symbol, getSymbolByAlter(tran.getSymbolRef())))
                result.add(tran);
        }
        return result;
    }