I had a similar problem. The default domain couldn't be created (default domain wasn't configured properly) and the logs stated "null" in bottom of commands. Fixed it but stopping any JDeveloper java processes, delete corrupted default domain from JDeveloper and its directory from file system (Ex: C:\Users\userName\AppData\Roaming\JDeveloper\system12.2.1.4.42.190911.2248\DefaultDomain) and then recreated it using JDeveloper.