private void deleteFolder(DefaultMutableTreeNode node) {
private void deleteFolder() { DefaultMutableTreeNode node = getSelectedNode();
  private void deleteFolder(DefaultMutableTreeNode node) {    if (node == root) return;    if (node == null) return;    int reply =       JOptionPane.showConfirmDialog(this,                                    "Delete folder and all its contents?",                                    "Delete Folder",                                    JOptionPane.OK_CANCEL_OPTION,                                    JOptionPane.PLAIN_MESSAGE);    if (reply == JOptionPane.OK_OPTION)      model.removeNodeFromParent(node);  }