uploadFile = new File(getServletContext().getRealPath("/images/" + fileName));
        } else if (checkFileType(fileName, fessConfig.getSupportedUploadedCssExtentionsAsArray())
                && checkFileType(uploadedFileName, fessConfig.getSupportedUploadedCssExtentionsAsArray())) {
            uploadFile = new File(getServletContext().getRealPath("/css/" + fileName));

                .get(stream -> stream.filter(StringUtil::isNotBlank).toArray(n -> new String[n]));
    }

    String getSupportedUploadedCssExtentions();

    default String[] getSupportedUploadedCssExtentionsAsArray() {
        return split(getSupportedUploadedCssExtentions(), ",")
                .get(stream -> stream.filter(StringUtil::isNotBlank).toArray(n -> new String[n]));
    }