@Test
  public void testDefaultValues() {

    WorkingTime workingTime = new WorkingTime();

    Assert.assertEquals("Wrong day length for monday", DayLength.ZERO, workingTime.getMonday());
    Assert.assertEquals("Wrong day length for tuesday", DayLength.ZERO, workingTime.getTuesday());
    Assert.assertEquals(
        "Wrong day length for wednesday", DayLength.ZERO, workingTime.getWednesday());
    Assert.assertEquals("Wrong day length for thursday", DayLength.ZERO, workingTime.getThursday());
    Assert.assertEquals("Wrong day length for friday", DayLength.ZERO, workingTime.getFriday());
    Assert.assertEquals("Wrong day length for saturday", DayLength.ZERO, workingTime.getSaturday());
    Assert.assertEquals("Wrong day length for sunday", DayLength.ZERO, workingTime.getSunday());

    Assert.assertFalse(
        "There should be no federal state override",
        workingTime.getFederalStateOverride().isPresent());
  }