Bug 208190 [Regression]A blank column occurs when export report to excel file[1203]
Description: Export report to excel file, a blank column is created on the front of the columns exported. Build version:2.3.0.v20071031-0800 Steps to reproduce: 1.Create a sample datasource and dataset. 2.Pull the dataset to the report layout,and add a group on the table. 3.Preview in web viewer, export the report to excel file, a blank column is created as the first column.
engine/org.eclipse.birt.report.engine.emitter.prototype.excel/src/org/eclipse/birt/report/engine/emitter/excel/layout/ExcelLayoutEngine.java
Rule rule = getCurrentContainer( ).getRule( );
		int start = rule.getStart( );
		int end = rule.getEnd( );
		int startcol = axis.getCoordinate( start );
		int endcol = axis.getCoordinate( end );
		int max = 0;
		int len[] = new int[endcol - startcol];
		for ( int i = startcol; i < endcol; i++ )
		{
			int columnsize = cache.getColumnSize( i - detal );
			len[i - startcol] = columnsize;
			max = max > columnsize ? max : columnsize;
		}
		for ( int i = startcol; i < endcol; i++ )
		{
			int rowspan = max - len[i - startcol];
			int last = len[i - startcol] - 1;
			if(rowspan > 0)
			{				
				Object data = null;				
				Object upstair =  cache.getData( i - detal, last );
				
				if ( upstair != null && upstair != waste )
				{
					Data predata = (Data) upstair;
					int rs = predata.getRowSpan( ) + rowspan;
					predata.setRowSpan( rs );
					data = predata;
				}
				else