code: private void addCodeContainer(Chart chart) {
          Label codeContainer = new Label("code", new StringFromResourceModel(
                  chart.getOptions().getClass(), chart.getOptions().getClass().getSimpleName()
                  + ".java"));
          codeContainer.setOutputMarkupId(true);
          add(codeContainer);
      }
docs: Adds a code container corresponding to the current chart
  @param chart The currently selected chart