@Override
	public List<GTreeNode> generateChildren() {
		List<GTreeNode> list = new ArrayList<>();
		for (Archive element : archiveManager.getAllArchives()) {
			GTreeNode node = createArchiveNode(element, dtFilterState);
			if (node != null) {
				list.add(node);
			}
		}
		Collections.sort(list);
		return list;
	}
This implementation returns null, since this class is the root of the hierarchy and does
not have an archive.
@see ghidra.app.plugin.core.datamgr.tree.DataTypeTreeNode#getArchiveNode()
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/datamgr/tree/ArchiveRootNode.java