RectangleEdge rangeAxisLocation = plot.getRangeAxisEdge();

        // Y0
        Number value0 = dataset.getEndValue(row, column);
        if (value0 == null) {
            return;
        }
        double java2dValue0 = rangeAxis.valueToJava2D(value0.doubleValue(),
        		dataArea, rangeAxisLocation);

        // Y1
        Number value1 = dataset.getStartValue(row, column);
        if (value1 == null) {
            return;
        }
        double java2dValue1 = rangeAxis.valueToJava2D(
                value1.doubleValue(), dataArea, rangeAxisLocation);

        if (java2dValue1 < java2dValue0) {
            double temp = java2dValue1;
            java2dValue1 = java2dValue0;
            java2dValue0 = temp;
            Number tempNum = value1;
            value1 = value0;
            value0 = tempNum;