private static int headerSizeFor(int encodedAttributeId,
                                     int sizeOrRefId) {
      if (fitsTinyEntry(encodedAttributeId, sizeOrRefId)) {
        return SMALLEST_HEADER_SIZE;
      }
      else if (fitsMediumEntry(encodedAttributeId, sizeOrRefId)) {
        return MEDIUM_HEADER_SIZE;
      }
      else {
        return BIG_HEADER_SIZE;
      }
    }
private static int headerSizeFor(int encodedAttributeId,
                                     int sizeOrRefId)