code: private String formatExemplarLocation(TimeZone tz) {
          String location = getTimeZoneNames().getExemplarLocationName(ZoneMeta.getCanonicalCLDRID(tz));
          if (location == null) {
              // Use "unknown" location
              location = getTimeZoneNames().getExemplarLocationName(UNKNOWN_ZONE_ID);
              if (location == null) {
                  // last resort
                  location = UNKNOWN_LOCATION;
              }
          }
          return location;
      }
docs: Private method returning the time zone's exemplar location string.
  This method will never return null.
  
  @param tz the time zone
  @return the time zone's exemplar location name.