Detect file drag'n'drop events in JOGL/NEWT GLWindow

The GLWindow provides methods to add callback listeners for mouse events, key events and window events (such as resize events), but how can we detect file drag-and-drop events, akin to the java.awt DropTarget?

The motivation here is to handle drag-and-drop events in Processing using its JOGL-based rendering modes (P2D and P3D), which automatically create a GLWindow for the sketch to run in.

Under NEWT Usage:

NewtCanvasAWT, representing an AWT Canvas, allows you to hook a NEWT Window into it.

I have tried the following, although I don't know whether this should work. Either way, it isn't.

var window = new NewtCanvasAWT(glWindow);
window.setDropTarget(new DropTarget(window, DnDConstants.ACTION_COPY_OR_MOVE, new DropTargetListener() {
    @Override
    public void dragEnter(DropTargetDragEvent dtde) {
        System.out.println("test");
    }
    @Override
    public void dragOver(DropTargetDragEvent dtde) {
        System.out.println("test");
    }
    @Override
    public void dropActionChanged(DropTargetDragEvent dtde) {
        System.out.println("test");
    }
    @Override
    public void dragExit(DropTargetEvent dte) {                 
        System.out.println("test");
    }
    @Override
    public void drop(DropTargetDropEvent dtde) {
        System.out.println("test");
    }
}));