code: @Override
  	public ObjectJS executeJson(ActionContext context, StringifierFactory jsonStringifierFactory, Simon simon) {
  		ObjectJS callTreeJS;
  		if (isCallTreeCallbackRegistered(context)) {
  			CallTree callTree = getData(simon);
  			if (callTree == null) {
  				callTreeJS = jsonMessage(NO_DATA_MESSAGE, jsonStringifierFactory);
  			} else {
  				callTreeJS = ObjectJS.create(callTree, jsonStringifierFactory);
  				callTreeJS.setAttribute("rootNode", jsonTreeNode(callTree.getRootNode(), jsonStringifierFactory));
  			}
  		} else {
  			callTreeJS = jsonMessage(NO_CALLBACK_MESSAGE, jsonStringifierFactory);
  		}
  		return callTreeJS;
  	}
docs: Generate a JSON call tree object or an error string if no call tree