@Nullable
  public RepositoryTreeNode getSelectedNode() {
    TreePath selection = myRepositoryTree.getSelectionPath();
    if (selection != null && selection.getLastPathComponent() instanceof RepositoryTreeNode) {
      return (RepositoryTreeNode)selection.getLastPathComponent();
    }
    return null;
  }
@Nullable
  public RepositoryTreeNode getSelectedNode()