public XYItemRenderer getRenderer() {
        return getRenderer(0);
    }

    /**
     * Returns the renderer for a dataset, or <code>null</code>.
     *
     * @param index  the renderer index.
     *
     * @return The renderer (possibly <code>null</code>).
     *
     * @see #setRenderer(int, XYItemRenderer)
     */
    public XYItemRenderer getRenderer(int index) {
        XYItemRenderer result = null;
        if (this.renderers.size() > index) {
            result = (XYItemRenderer) this.renderers.get(index);
        }
        return result;