@Override
 public void persist(String colFamily, byte[] rowKey, List<Column> columns) {
   Persist persist = new Persist();
   persist.setColFamily(colFamily);
   persist.setRowKey(rowKey);
   persist.setColumns(columns);
   actions.add(persist);
 }
 private void insertTime(Action action, long time) {
   if (action instanceof Persist) {
     ((Persist) action).setTimestamp(time);
   }
 }