code: private synchronized long catchUp(long nextSequenceNumber) {
      JournalReader journalReader = new UfsJournalReader(this, nextSequenceNumber, true);
      try {
        return catchUp(journalReader);
      } finally {
        try {
          journalReader.close();
        } catch (IOException e) {
          LOG.warn("Failed to close journal reader: {}", e.toString());
        }
      }
    }
docs: Reads and applies all journal entries starting from the specified sequence number.
  
  @param nextSequenceNumber the sequence number to continue catching up from
  @return the next sequence number after the final sequence number read