JDL-Studio is a great tool but you have to have an internet connection to use it.
How do you create an UML image from a JDL file from the commandline?
I searched the jhipster-uml help section, the jhipster-uml documentation site, and google to try to find the answer to this question. But all the resources I've been able to find discuss generation in the opposite direction. All the instructions tell how to generate code from UML or from JDL.
Is there a simple command that can be executed from the command line that takes a *.jdl file as input and outputs a file with the generated UML just like the JDL-Studio does?
there is no such tool because "UML" files are based on a spec implemented by UML editors (Modelio, Visual Paradigm, etc). However, you can clone the JDL studio repo, launch the app, and have it offline if you want