presto-main/src/main/java/io/prestosql/operator/scalar/UrlFunctions.java/UrlFunctions/parseUrl
class UrlFunctions:    @Nullable
    private static URI parseUrl(Slice url)
    {
        try {
            return new URI(url.toStringUtf8());
        }
        catch (URISyntaxException e) {
            return null;
        }
    }