Java SE (Java Platform, Standard Edition)

I'd like to create a top level window (Window, Dialog, Frame, etc) with the following properties. I'm working on Ubuntu and Windows, but have tried so far only on Ubuntu.

* No window list (taskbar) item
* Does not need to be on top of it's parent
* Can be focused / decorated

I think I've tried each of the following, but maybe I'm missing something or perhaps there is a way to extend one of these classes to do what I want.

JWindow: If it doesn't have a parent, it can't get focus. If it does have a parent, it demands to be on top of it. Additionally, it's not decorated, so I'd have to do that myself.

JDialog: If it doesn't have a parent, it has it's own item in the window list (taskbar). If it does have a parent, it demands to be on top of it.

JFrame: Always has it's own item in the window list.

I feel like the approach is to start with a JWindow and get it decorated and allow it to be focusable without giving it a parent. Alternatively, start with a JWindow and get it decorated and give it a parent but remove the typical parent-child window relationships: Z-order, window state, Z-order relative to other applications, etc.

I'm aware that such a window could be "lost" in that there's no way to get to it from the window list. I don't care about that.

Thoughts? Known solutions?