private static VirtualFile @Nullable [] extractVirtualFiles(@NotNull List<MavenSimpleNode> selectedNodes) {
    final List<VirtualFile> files = new ArrayList<>();
    for (MavenSimpleNode each : selectedNodes) {
      VirtualFile file = each.getVirtualFile();
      if (file != null && file.isValid()) files.add(file);
    }
    return files.isEmpty() ? null : VfsUtilCore.toVirtualFileArray(files);
  }
private static VirtualFile @Nullable [] extractVirtualFiles(@NotNull List<MavenSimpleNode> selectedNodes)