空指针

看不懂空指针，没救了，很不幸说的是我自己

List<CarNoModel> carNoResult = incomingService.queryCarNo(carNoModel,sysName);
        if(carNoResult != null) {
            model.addObject("list", net.sf.json.JSONArray.fromObject(carNoResult));
        }else {
            CarNoModel c = new CarNoModel();
            c.setCarNo("未查到数据");
            carNoResult.add(c);
            model.addObject("list", net.sf.json.JSONArray.fromObject(carNoResult));
        }

当 carNoResult没空的时候，null当然就加不了啊，也就add不了啊，真的是睿智了，----------------------------------

所以要，再new一个出来啊，笨啊遭人嫌弃啊，carNoResult = new ArrayList<carNoResult>();

List<CarNoModel> carNoResult = incomingService.queryCarNo(carNoModel,sysName);
        if(carNoResult != null) {
            model.addObject("list", net.sf.json.JSONArray.fromObject(carNoResult));
        }else {
            CarNoModel c = new CarNoModel();
            c.setCarNo("未查到数据");
            carNoResult = new ArrayList<CarNoModel>();
            carNoResult.add(c);
            model.addObject("list", net.sf.json.JSONArray.fromObject(carNoResult));
        }

好好学习，天天向上