It seems that svn has gone down.
NetBeans, the svn command, and even attempting to go directly to
https://svn.dev.java.net/svn/glassfish-svn in a browser all give:
svn: PROPFIND request failed on
'/svn/glassfish-svn/trunk/v3/appclient/client/acc'
svn: Could not open the requested SVN filesystem
- Tim