@NotNull
  public static String getGroovyLibraryHome(Library library) {
    final VirtualFile[] classRoots = library.getFiles(OrderRootType.CLASSES);
    final String home = getGroovyLibraryHome(classRoots);
    return home == null ? "" : home;
  }
@NotNull
  public static String getGroovyLibraryHome(Library library)