public String dump() throws IOException {
      StringBuilder sb =
        new StringBuilder("HeaderLayout[size: " + headerSegmentSize + "b, globalHashSuffixSize: " + globalHashSuffixDepth() + "]");
      sb.append("[tableSize: " + segmentTableSize() + ", actualSegments: " + actualSegmentsCount() + "]\n");
      for (int i = 0; i < segmentTableSize(); i++) {
        sb.append("\t[" + i + "]=" + segmentIndex(i) + "\n");
      }
      return sb.toString();
    }
public String dump()