code: public Map<RowColumn, Bytes> getOperationMap(LogEntry.Operation op) {
      Map<RowColumn, Bytes> opMap = new HashMap<>();
      for (LogEntry entry : logEntries) {
        if (entry.getOp().equals(op)) {
          opMap.put(new RowColumn(entry.getRow(), entry.getColumn()), entry.getValue());
        }
      }
      return opMap;
    }
docs: Returns a map of RowColumn changes given an operation