code: static boolean hasUnixChronology(Chronology<?> chronology) {
  
          Chronology<?> c = chronology;
  
          do {
              if (UnixTime.class.isAssignableFrom(c.getChronoType())) {
                  return true;
              }
          } while ((c = c.preparser()) != null);
  
          return false;
  
      }
docs: also called in PatternType