To add this topic to your website, copy and paste the following code on your HTML page:
<a id="nabblelink" href="http://deprecated-apache-flink-user-mailing-list-archive.369.s1.nabble.com/map-can-t-return-null-tp30269.html">map can't return null</a> <script src="http://deprecated-apache-flink-user-mailing-list-archive.369.s1.nabble.com/embed/p30269"></script>
You can embed this topic in more than one website.
We suggest that you use a custom domain name to avoid third-party cookie problems.
Please check the Nabble Help for more information.