double[] xData = new double[] { 0.0, 1.0, 2.0, 3.0, 4.0, 5, 6 };
double[] yData = new double[] { 106, 44, 26, 10, 7.5, 3.4, .88 };
double[] yData2 = new double[] { 102, 49, 23.6, 11.3, 5.4, 2.6, 1.25 };
Series series = chart.addSeries("A", xData, yData);
series.setLineStyle(SeriesLineStyle.NONE);
series.setMarker(SeriesMarker.DIAMOND);
series.setMarkerColor(Color.BLACK);
Series series2 = chart.addSeries("B", xData, yData2);