Versi semasa boleh dijalankan, tetapi tulisannya pasti tidak bagus.

List<? extends WeatherData> data =  weatherReportDao.getCoviReportData(reportType);
WeatherENUM weatherENUM = WeatherENUM.valueOf(reportFunction);
switch (weatherENUM){
            case atmosphere:
                data =  atmosphereReportDao.getAtmosphereReportData(reportType);
                break;
            case covi:
                 data =  weatherReportDao.getCoviReportData(reportType);
                break;
            case windSpeed:
                data = windSpeedReportDao.getWindSpeedReportData(reportType);
                break;
        }
        return data;

Kuncinya ialah pemulaan data Jika tidak dimulakan, ralat akan dilaporkan. Minta tunjuk ajar.