static GroupBy newInstanceForRowID( GroupSpec groupDefn )
public static GroupBy newInstanceForRowID( GroupSpec groupDefn )
	static GroupBy newInstanceForRowID( GroupSpec groupDefn )			throws DataException	{		assert groupDefn != null;		GroupBy groupBy = null;		switch ( groupDefn.getInterval( ) )		{			case GroupSpec.NO_INTERVAL :				groupBy = new GroupByDistinctValue( );				break;			case GroupSpec.NUMERIC_INTERVAL :				groupBy = new GroupByPositionRange( groupDefn );				break;			default :				throw new DataException( ResourceConstants.BAD_GROUP_INTERVAL_TYPE_ROWID );		}		groupBy.groupSpec = groupDefn;		groupBy.columnIndex = -1;		return groupBy;	}