private static Object @NotNull [] createArrayAddAll(Object @NotNull [] elements, Object @NotNull [] cs) {
    int len = elements.length;
    Object[] newElements = Arrays.copyOf(elements, len + cs.length, Object[].class);
    System.arraycopy(cs, 0, newElements, len, cs.length);
    return newElements;
  }
private static Object @NotNull [] createArrayAddAll(Object @NotNull [] elements, Object @NotNull [] cs)