CartesianChartModel model = (CartesianChartModel) chart.getModel();
Map<AxisType,Axis> axes = model.getAxes();
writer.write(",axes:{");
for(Iterator<AxisType> it = axes.keySet().iterator(); it.hasNext();) {
AxisType axisType = it.next();
Axis axis = model.getAxes().get(axisType);
encodeAxis(context, axisType, axis);
if(it.hasNext()) {