XYToolTipGenerator generator = getToolTipGenerator(series, item);
        if (generator != null) {
            tip = generator.generateToolTip(dataset, series, item);
        }
        String url = null;
        if (getURLGenerator() != null) {
            url = getURLGenerator().generateURL(dataset, series, item);
        }
        XYItemEntity entity = new XYItemEntity(hotspot, dataset, series, item,
                tip, url);
        entities.add(entity);