@Override
	public Iterator<GTreeNode> iterator(boolean depthFirst) {
		if (Swing.isSwingThread()) {
			Msg.warn(this, "Threaded tree nodes cannot be iterated on the Swing thread. " +
				"Change the call to this method to be run in a background task");
			return IteratorUtils.emptyIterator();
		}
		return super.iterator(depthFirst);
	}
Subclass must implement this method to generate their children. This operation will always be
performed in a background thread (i.e. Not the swing thread)

@param monitor a TaskMonitor for reporting progress and cancel notification.
@return the list of children for this node.
@throws CancelledException if the monitor is cancelled
Ghidra/Framework/Docking/src/main/java/docking/widgets/tree/GTreeSlowLoadingNode.java