@NotNull
  private Collection<AntBuildFileBase> getSelectedBuildFiles() {
    if (myTree == null) {
      return Collections.emptyList();
    }
    final TreePath[] paths = myTree.getSelectionPaths();
    if (paths == null) {
      return Collections.emptyList();
    }
    final Set<AntBuildFileBase> result  = new HashSet<>();
    for (TreePath path : paths) {
      DefaultMutableTreeNode node = (DefaultMutableTreeNode)path.getLastPathComponent();
      while (node != null) {
        final Object userObject = node.getUserObject();
        if (userObject instanceof AntBuildFileNodeDescriptor) {
          final AntBuildFileBase file = (AntBuildFileBase)((AntBuildFileNodeDescriptor)userObject).getBuildFile();
          if (file != null) {
            result.add(file);
          }
          break;
        }
        node = (DefaultMutableTreeNode)node.getParent();
      }
    }
    return result;
  }
@NotNull
  private Collection<AntBuildFileBase> getSelectedBuildFiles()