@Test public void testSerializeCalendar() throws Exception { int year = 1990; int month = 11; int day = 15; int hour = 10; int minute = 50; int seconds = 30; int milliseconds = 123; Calendar calendar = Calendar.getInstance(); calendar.setTimeZone(TimeZone.getTimeZone("UTC")); calendar.set(year, month - 1, day, hour, minute, seconds); calendar.set(Calendar.MILLISECOND, milliseconds); CalendarSerializer calendarSerializer = new CalendarSerializer(); String strDate = calendarSerializer.serialize(calendar, Calendar.class, null).toString(); // yyyy-MM-dd'T'HH:mm:ss'.'SSS'Z String expectedDate = String.format( "\"%s-%d-%sT%s:%s:%s.%sZ\"", year, month, day, hour, minute, seconds, milliseconds); assertEquals(expectedDate, strDate); }