@Override
  public void validate(String value, @Nullable List<String> options) {
    try {
      Integer.parseInt(value);
    } catch (NumberFormatException e) {
      throw BadRequestException.create(format("Value '%s' must be an integer.", value));
    }
  }
@Test
  public void fail_on_float() {

    assertThatThrownBy(() -> validation.validate("10.1", null))
      .isInstanceOf(BadRequestException.class)
      .hasMessage("Value '10.1' must be an integer.");
  }