if (cDNodes == null) return;
if (cDNodes.size() == 0) return;
    void refreshDatasetInTree(DatasetSummary ds)    {        if (cDNodes == null) return;        List nodes = (List) cDNodes.get(new Integer(ds.getID()));        if (nodes == null) return;        Iterator i = nodes.iterator();        DefaultTreeModel treeModel = (DefaultTreeModel) view.tree.getModel();        DefaultMutableTreeNode node, childNode;           List images = agentCtrl.getImages(ds.getID());        while (i.hasNext()) {            node = (DefaultMutableTreeNode) i.next();            node.removeAllChildren();            if (images.size() != 0)                addImagesToDataset(images, node);                else {                childNode = new DefaultMutableTreeNode(EMPTY);                treeModel.insertNodeInto(childNode, node,                     node.getChildCount());                        }             treeModel.reload(node);        }           }