protected int getWeight(Object element) {
    if (element instanceof File) {
      return 10;
    }
    if (element instanceof ModuleDescriptor) {
      return 20;
    }
    if (element instanceof LibraryDescriptor) {
      return ((LibraryDescriptor)element).getJars().size() > 1? 30 : 40;
    }
    return Integer.MAX_VALUE;
  }
protected int getWeight(Object element)