docs: public static ARouter getInstance() {
          if (!hasInit) {
              throw new InitException("ARouter::Init::Invoke init(context) first!");
          } else {
              if (instance == null) {
                  synchronized (ARouter.class) {
                      if (instance == null) {
                          instance = new ARouter();
                      }
                  }
              }
              return instance;
          }
      }