jogl without a canvas - can it be done?

Firstly, I’m new to jogl and OpenGL, so I’m slowly feeling my way around the API…and getting pretty lost…

I’m trying to create a cmdline rendering application, where [obviously!] no images are actually displayed by my app.
All I need my app to do is take inputs and write out an image file. In other words, all rendering should happen to an offscreen buffer.

There is one contraint so far that I have imposed: the app needs to work with graphics cards that do not have pbuffer support.

Is it actually possible to create a cmdline utility using jogl? - all the demos I have seen so far all use onscreen canvases or pbuffers

Where on earth do I start?

A pbuffer is an offscreen buffer and is what you are looking for.