private BubbleChartModel initBubbleModel() {
    BubbleChartModel model = new BubbleChartModel();

    model.add(new BubbleChartSeries("Acura", 70, 183, 55));
    model.add(new BubbleChartSeries("Alfa Romeo", 45, 92, 36));
    model.add(new BubbleChartSeries("AM General", 24, 104, 40));
    model.add(new BubbleChartSeries("Bugatti", 50, 123, 60));
    model.add(new BubbleChartSeries("BMW", 15, 89, 25));
    model.add(new BubbleChartSeries("Audi", 40, 180, 80));
    model.add(new BubbleChartSeries("Aston Martin", 70, 70, 48));

    return model;
  }
  private void createBubbleModels() {
    bubbleModel1 = initBubbleModel();
    bubbleModel1.setTitle("Bubble Chart");
    bubbleModel1.getAxis(AxisType.X).setLabel("Price");
    Axis yAxis = bubbleModel1.getAxis(AxisType.Y);
    yAxis.setMin(0);
    yAxis.setMax(250);
    yAxis.setLabel("Labels");

    bubbleModel2 = initBubbleModel();
    bubbleModel2.setTitle("Custom Options");
    bubbleModel2.setShadow(false);
    bubbleModel2.setBubbleGradients(true);
    bubbleModel2.setBubbleAlpha(0.8);
    bubbleModel2.getAxis(AxisType.X).setTickAngle(-50);
    yAxis = bubbleModel2.getAxis(AxisType.Y);
    yAxis.setMin(0);
    yAxis.setMax(250);
    yAxis.setTickAngle(50);
  }