@Test
public void testAreEqual() {

    assertTrue(CalendarUtils.areEqual(null, null));
    Calendar calendar = Calendar.getInstance();
    Date now = calendar.getTime();
    assertFalse(CalendarUtils.areEqual(now, null));
    assertFalse(CalendarUtils.areEqual(null, now));
    assertTrue(CalendarUtils.areEqual(now, now));
    calendar.add(Calendar.HOUR_OF_DAY, 1);
    assertFalse(CalendarUtils.areEqual(now, calendar.getTime()));
}