code: public static boolean needsHeatmapJs(final Options options) {
          return
                  options.getChart() != null &&
                          (options.getChart().getType() == SeriesType.HEATMAP);
      }
docs: Checks if the specified Options object needs the javascript file
  "heatmap.js" to work properly. This method can be called by GUI
  components to determine whether the javascript file has to be included in
  the page or not.
  
  @param options the {@link Options} object to analyze
  @return true, if "funnel.js" is needed to render the options,
  false if not