code: public void setTimeZoneID(String timeZoneId) {
          if (verifyTimeZoneID(timeZoneId)) {
              this.timeZone = TimeZone.getTimeZone(timeZoneId);
          } else {
              throw new IllegalArgumentException(timeZoneId + " is not a valid time zone");
          }
  
      }
docs: Sets the ID of the time zone to be used in the formatted log record header timestamp
  
  @param timeZoneId new timeZoneID attribute value.
  
  @throws IllegalArgumentException when the time zone ID is not valid.