public DataPoint addDataPoint(Object label) {
        DataPoint dp = new DataPoint();
        labels.add(label);
        dataPoints.add(dp);
        return dp;
    }
@Test(expected = IllegalArgumentException.class)
    public void dataPointBandSeries() {
        cm = new ChartModel(FOO, BAR);

        cm.addDataPoint(System.currentTimeMillis())
                .data(ZOO, VALUES3[0]);
    }