question: @ Override public void start ( Stage stage ) throws Exception { CategoryDataset dataset = createDataset ( ) ; JFreeChart chart = createChart ( dataset ) ; ChartViewer viewer = new ChartViewer ( chart ) ; viewer . addChartMouseListener ( this ) ; stage . setScene ( new Scene ( viewer ) ) ; stage . setTitle ( "JFreeChart: BarChartFXDemo1.java" ) ; stage . setWidth ( 700 ) ; stage . setHeight ( 390 ) ; stage . show ( ) ; }
target:  Adds a chart viewer to the stage and displays it.