headers = DataSetManager.getCurrentInstance( )
headers = ChartDataSetManager.getCurrentInstance( )
	protected DataSetItemModel[] getPreviewHeaderModel( )	{		DataSetItemModel[] headers = null;		try		{			headers = DataSetManager.getCurrentInstance( )					.getCacheMetaData( getDataSetFromHandle( ),							itemHandle.getPropertyHandle( ExtendedItemHandle.PARAM_BINDINGS_PROP )									.iterator( ) );			isErrorFound = false;		}		catch ( BirtException e )		{			WizardBase.displayException( e );			isErrorFound = true;		}		return headers;	}