@Override
   public String getColumnName(int col) {
      return (col < header.length) ? columnMapping.get(header[col].toUpperCase()) : null;
   }
@Override
   public String getColumnName(int col) {
      return (col < header.length) ? columnMapping.get(header[col].toUpperCase()) : null;
   }
@ Override public String getColumnName ( int col ) { return ( col < header . length ) ? columnMapping . get ( header [ col ] . toUpperCase ( ) ) : null ; }
Retrieves the column name for a given column position

@param col - column position.
@return - The column name.
Retrieves the column name for a given column position