Bug 138562 Splite extendsexcpetion to seperate sub class
The suggestion is Parent invalid Cycle extends Different type extends Not top level extends
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ElementFactory.java
* @param columnNum
	 *            column number of the grid. If it is less than 0, none column
	 *            will be added.
	 * @param rowNum
	 *            row number of the grid. If it is less than 0, none row will be
	 *            added.
	 * 
	 * @return a handle to the grid item
	 */
	public GridHandle newGridItem( String name, int columnNum, int rowNum )
	{
		GridHandle gridHandle = newGridItem( name );
		GridItem grid = (GridItem) gridHandle.getElement( );
		columnNum = columnNum >= 0 ? columnNum : 0;
		rowNum = rowNum >= 0 ? rowNum : 0;
		for ( int i = 0; i < columnNum; i++ )
		{
			TableColumn column = new TableColumn( );
			grid.getSlot( GridItem.COLUMN_SLOT ).add( column );
			column.setContainer( grid, GridItem.COLUMN_SLOT );
		}
		for ( int i = 0; i < rowNum; i++ )
		{
			TableRow row = (TableRow) newTableRow( columnNum ).getElement( );
			grid.getSlot( GridItem.ROW_SLOT ).add( row );
			row.setContainer( grid, GridItem.ROW_SLOT );
		}
		return gridHandle;
	}
	/**