@Override
 public Map<RowColumn, Bytes> get(Collection<RowColumn> rowColumns) {
   return tx.get(rowColumns);
 }
 @Override
 public Map<Column, Bytes> get(Bytes row, Set<Column> columns) {
   return tx.get(row, columns);
 }
 @Override
 public Map<Bytes, Map<Column, Bytes>> get(Collection<Bytes> rows, Set<Column> columns) {
   return tx.get(rows, columns);
 }
 @Override
 public Bytes get(Bytes row, Column column) {
   return tx.get(row, column);
 }