public function validateAttribute($object, $attribute)
    {
        //decrement the columnCount by 1 as we are starting with 0
        $this->columnCount--;

        $file = $object->$attribute;
        if(!$file instanceof CUploadedFile) {
            $file = CUploadedFile::getInstance($object, $attribute);
            if(null===$file)
                return $this->emptyAttribute($object, $attribute);
        }

        $this->validateCSVHeaders($object, $attribute, $file);
    	$this->validateCSVRows($object, $attribute, $file);
    }