Bug 214577 Support cube filter in chart
For chart consuming cube, need to support filtering on categories or series, possibly on values if time allows. The UI is similar to the filter dialog for cross tab, but there should be no measure or dimension concepts in chart's dialog.
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/ReportDataServiceProvider.java
* 
	 */
	private List generateComputedColumns( ReportItemHandle handle )
			throws SemanticException
	{
		DataSetHandle dataSetHandle = handle.getDataSet( );
		if ( dataSetHandle == null )
		{
			dataSetHandle = DEUtil.getBindingHolder( handle ).getDataSet( );
		}
		if ( dataSetHandle != null )
		{
			List resultSetColumnList = DataUtil.getColumnList( dataSetHandle );
			ArrayList columnList = new ArrayList( );
			for ( Iterator iter = resultSetColumnList.iterator( ); iter.hasNext( ); )
			{
				ResultSetColumnHandle resultSetColumn = (ResultSetColumnHandle) iter.next( );
				ComputedColumn column = StructureFactory.newComputedColumn( handle,
						resultSetColumn.getColumnName( ) );
				column.setDataType( resultSetColumn.getDataType( ) );
				column.setExpression( DEUtil.getExpression( resultSetColumn ) );
				columnList.add( column );
			}
			return columnList;
		}
		return Collections.EMPTY_LIST;
	}
	/**
	 * Gets dataset from ReportItemHandle at first. If null, get dataset from
	 * its container.