public static Builder forPage(int page) {
    return new Builder(page);
  }
@Test
  void forPage_fails_with_IAE_if_page_is_less_than_0() {
    assertThatThrownBy(() -> forPage(-Math.abs(new Random().nextInt()) - 1))
      .isInstanceOf(IllegalArgumentException.class)
      .hasMessage("page index must be >= 1");
  }