code: private List<MergedIndexEntry> getAllEntries(long offsetAdjustment) {
          Exceptions.checkArgument(offsetAdjustment >= 0, "offsetAdjustment", "offsetAdjustment must be a non-negative number.");
  
          synchronized (this.lock) {
              List<MergedIndexEntry> result = new ArrayList<>(this.indexEntries.size());
              this.indexEntries.forEach(entry -> {
                  if (entry.isDataEntry()) {
                      result.add(new MergedIndexEntry(entry.getStreamSegmentOffset() + offsetAdjustment, this.metadata.getId(), (CacheIndexEntry) entry));
                  }
              });
  
              return result;
          }
      }
docs: Gets a copy of all the ReadIndexEntries in this Index that are not RedirectReadIndices. All returned
  entries have their offsets adjusted by the given amount.
  
  @param offsetAdjustment The amount to adjust the offset by.