List<JournalEntry> getAllEntries() {
    List<JournalEntry> result = new ArrayList<>();
    // get current last Offset
    Offset lastOffset = getLastOffset();
    journal.entrySet();
    if (lastOffset != null) {
      // get portion view of journal whose key is less than or equal to lastOffset
      NavigableMap<Offset, StoreKey> journalView = journal.headMap(lastOffset, true);
      for (Map.Entry<Offset, StoreKey> entry : journalView.entrySet()) {
        result.add(new JournalEntry(entry.getKey(), entry.getValue()));
      }
    }
    return result;
  }
@return all journal entries at the time when this method is invoked. (Return empty list if journal is empty)
ambry-store/src/main/java/com/github/ambry/store/Journal.java