in src/main/java/org/apache/sling/contentparser/api/ParserHelper.java [101:108]
private static Calendar parseDate(String string, DateTimeFormatter formatter) {
final ZonedDateTime zonedDateTime = ZonedDateTime.parse(string, formatter);
final Instant instant = zonedDateTime.toInstant();
Calendar calendar = Calendar.getInstance();
calendar.setTime(Date.from(instant));
calendar.setTimeZone(TimeZone.getTimeZone(zonedDateTime.getOffset()));
return calendar;
}