code: private void quarantineSegment(Map.Entry<Long, PBDSegment> prevEntry) throws IOException {
          quarantineSegment(prevEntry, prevEntry.getValue(), prevEntry.getValue().getNumEntries());
      }
docs: Quarantine a segment which was already added to {@link #m_segments}
  
  @param prevEntry {@link Map.Entry} from {@link #m_segments} to quarantine
  @throws IOException