public void checkOpen(MouseEvent e) {
		if (tool == null) { // dialog use
			return;
		}
		if (e.getButton() != MouseEvent.BUTTON1 || e.getClickCount() != 2) {
			return;
		}

		e.consume();
		Point point = e.getPoint();
		TreePath pathForLocation = tree.getPathForLocation(point.x, point.y);
		if (pathForLocation == null) {
			return;
		}

		GTreeNode node = (GTreeNode) pathForLocation.getLastPathComponent();
		if (!(node instanceof DomainFileNode)) {
			return;
		}

		DomainFile domainFile = ((DomainFileNode) node).getDomainFile();
		plugin.openDomainFile(domainFile);
	}
Create the root node for this data tree.
Ghidra/Framework/Project/src/main/java/ghidra/framework/main/datatree/ProjectDataTreePanel.java