previous midnight timezones

not-important.java

package com.koomho.datetime_test;

import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.ZoneOffset;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Arrays;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;
import java.util.TimeZone;

public class App {
  public static void main(String[] args) {
    
    ZonedDateTime previousFlatHourInUTC=ZonedDateTime.now()
      .withZoneSameInstant(ZoneOffset.UTC)
      .withMinute(0)
      .withSecond(0);

    //TRAVERSING THE TIMEZONES
    ZoneId.getAvailableZoneIds().parallelStream().forEach(zoneId -> {

          if(previousFlatHourInUTC.withZoneSameInstant(ZoneId.of(zoneId)).getHour() ==0)         
              System.out.println("PASSED MIDNIGHT at:"+zoneId);              
    });
  }
}