Failed attempt: JPA attribute converter to "force" dates into UTC when writing to the database (and reading again)

OffsetDateTimeConverter.java

/**
 * Failed experiment: Attempting to force datetimes to be written/loaded using the UTC time zone.
 *
 *
 * Good: OffsetDateTime is successfully converted into a "normal" Temporal data type ( here Calendar ) - resulting in Timestamp DDL etc.
 *
 * Bad : Datetimes are still stored using the JVM default time zone. ( In my part of the world: UTC+1 right now )
 *
 * The working solution I can come up with right now is setting the entire JVM into the UTC time zone. That surely does the job: Datetimes
 * in the database show up as UTC versions. 
 *
 * But setting the JVM into UTC seems like a crude solution to the problem at hand. Also note: I don't look for a driver specific solution.
 * So no "timestamp with timezone" solution.
 *
 */
@Converter(autoApply = true)
public class OffsetDateTimeConverter implements AttributeConverter<OffsetDateTime, Calendar> {

  private final static ZoneId TIME_ZONE = ZoneId.of("UTC");

  @Override
  public Calendar convertToDatabaseColumn(OffsetDateTime offsetDateTime) {
    Calendar calendar = Calendar.getInstance(TimeZone.getTimeZone(TIME_ZONE));
    // ( ^^ notice that the Calendar is created for a specific TimeZone ^^ )
    // ( this is my apparently naive attempt at "forcing" the time to be converted to UTC before being sent to the db )
    calendar.setTime(Date.from(offsetDateTime.toInstant()));
    return calendar;
  }

  @Override
  public OffsetDateTime convertToEntityAttribute(Calendar dbData) {
    Instant instant = dbData.toInstant();
    OffsetDateTime offsetDateTime = OffsetDateTime.ofInstant(instant, TIME_ZONE);
    return offsetDateTime;
  }

}

By the way: OffsetDateTime ... just happens to be what I like to use in my entities ;)

( by the way @thanssen : I did read your excellent post on using the hibernate8 library ... that works great ;) ... but I wanted to additionally ensure the UTC conversion ;) )