### Question:
DateFieldActions implements AtlasFieldAction { @AtlasActionProcessor(sourceType = FieldType.ANY_DATE) public static Integer dayOfWeek(DayOfWeek action, ZonedDateTime input) { return input == null ? null : input.getDayOfWeek().getValue(); }  @AtlasActionProcessor(sourceType = FieldType.ANY_DATE) static ZonedDateTime addDays(AddDays addDays, ZonedDateTime input); @AtlasActionProcessor(sourceType = FieldType.ANY_DATE) static ZonedDateTime addSeconds(AddSeconds addSeconds, ZonedDateTime input); @AtlasActionProcessor static ZonedDateTime currentDate(CurrentDate action); @AtlasActionProcessor static ZonedDateTime currentDateTime(CurrentDateTime action); @AtlasActionProcessor static ZonedDateTime currentTime(CurrentTime action); @AtlasActionProcessor(sourceType = FieldType.ANY_DATE) static Integer dayOfMonth(DayOfMonth action, ZonedDateTime input); @AtlasActionProcessor(sourceType = FieldType.ANY_DATE) static Integer dayOfWeek(DayOfWeek action, ZonedDateTime input); @AtlasActionProcessor(sourceType = FieldType.ANY_DATE) static Integer dayOfYear(DayOfYear action, ZonedDateTime input);  }### Answer:
@Test public void testDayOfWeek() { assertNull(DateFieldActions.dayOfWeek(null, null)); ZonedDateTime origDate = LocalDate.of(2017, 12, 14).atStartOfDay(ZoneId.systemDefault()); assertEquals(Integer.valueOf(4), DateFieldActions.dayOfWeek(null, origDate)); }