@Contract(value = "null -> null; !null -> !null", pure = true)
  public static boolean @Nullable [] copyOf(boolean @Nullable [] original) {
    if (original == null) return null;
    return original.length == 0 ? ArrayUtilRt.EMPTY_BOOLEAN_ARRAY : original.clone();
  }
@Contract(value = "null -> null; !null -> !null", pure = true)
  public static boolean @Nullable [] copyOf(boolean @Nullable [] original)