Program to help work out time correspondence between timezones

TimeTabulator.java

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class TimeTabulator {

    public static void main(String[] args) {
        tabulate(LocalDate.of(2019, 12, 26),
                 ZoneId.of("Europe/London"),
                 List.of(ZoneId.of("America/Vancouver"),
                         ZoneId.of("Pacific/Auckland")));
    }

    private static void tabulate(LocalDate referenceDate, ZoneId primaryZone, List<ZoneId> secondaryZones) {
        for (LocalDateTime now = LocalDateTime.of(referenceDate, LocalTime.MIDNIGHT); now.toLocalDate().equals(referenceDate); now = now.plusHours(1)) {
            ZonedDateTime primaryTime = now.atZone(primaryZone);

            System.out.println(Stream.concat(Stream.of(primaryTime),
                                             secondaryZones.stream()
                                                           .map(primaryTime::withZoneSameInstant))
                                     .map(time -> formatRelative(time, referenceDate))
                                     .collect(Collectors.joining(" = ")));
        }
    }

    private static String formatRelative(ZonedDateTime time, LocalDate referenceDate) {
        long dateOffset = time.toLocalDate().toEpochDay() - referenceDate.toEpochDay();

        return String.format("%3s %s %s",
                             dateOffset == 0 ? "" : String.format("%+dd", dateOffset),
                             time.toLocalTime(),
                             time.getZone().getId().split("/")[1]);
    }

}