code: public static Diagram parseJson(String json,
                                      Boolean keepGlossaryLink) throws JSONException {
          JSONObject modelJSON = new JSONObject(json);
          return parseJson(modelJSON,
                           keepGlossaryLink);
      }
docs: Parse the json string to the diagram model, assumes that the json is
  hierarchical ordered
  @param json
  @return Model with all shapes defined in JSON
  @throws org.json.JSONException