public RowBuilder int16(String name){
  ColumnInt16 column=new ColumnInt16(_columns.size(),name,_offset);
  _offset+=column.length();
  _columns.add(column);
  return this;
}

public RowBuilder int16 ( String name ) { ColumnInt16 column = new ColumnInt16 ( _columns . size ( ) , name , _offset ) ; _offset += column . length ( ) ; _columns . add ( column ) ; return this ; }
creates a 16 - bit integer valued column
