Fatal error: Cannot instantiate abstract class Hoa_File in C:\wamp\www\ivelo.fr\Framework\Module\Weather\Weather.php on line 133

        if (is_null($city_code))
            throw new Hoathis_Weather_Exception('Argument 1: city_code could not be null', 0);

        $this->city_code = $city_code;
        $this->lang = $lang;

        Hoa_Stream_Context::getInstance('google_weather', 'http')->addOptions(array(
            'timeout' => 30
        ));

        try {

            $content = new Hoa_File(
                sprintf(self::URL, urlencode($this->city_code), $this->lang),
                Hoa_File::MODE_READ,
                'google_weather'
            );
        }
        catch ( Hoa_File_Exception $e ) {

            throw new Hoathis_Weather_Exception(
                $e->getFormattedMessage(),
                $e->getCode()
            );
        }

        $this->reponse = Hoa_Xml::parse(utf8_encode($content->readAll()), null);

        if (!$this->reponse)
            throw new Hoa_Weather_Exception('Parsing error', 1);

        if (isset($xml->weather->problem_cause))
            throw new Hoa_Weather_Exception('Service weather not found', 2);

        $this->getCurrentCity();
        $this->getCurrentConditions();
        $this->getForecastConditions();

        return $this->current_conditions;

$content = new Hoa_File(