code: @SuppressWarnings("unchecked")
  	private void collectDrilldownOptions(final Options options) {
  		List<? extends IProcessableOption> drilldownPoints = options.getMarkedForProcessing(DrilldownPoint.PROCESSING_KEY);
  		for (DrilldownPoint drilldownPoint : (List<DrilldownPoint>) drilldownPoints) {
  			Options drilldownOptions = drilldownPoint.getDrilldownOptions();
  			if (!getDrilldownOptions().contains(drilldownOptions)) {
  				getDrilldownOptions().add(drilldownOptions);
  				collectDrilldownOptions(drilldownOptions);
  			}
  			drilldownPoint.setDrilldownOptionsIndex(getDrilldownOptions().indexOf(drilldownOptions));
  		}
  	}
docs: Iterates recursively through all {@link DrilldownPoint}s and their
  drilldownOptions in the given {@link Options} and adds them to the context.