code: function () {
  
      if (this.initialized) {
        return;
      }
  
      this.structure = cache.get(CONST.SYSTEM_DB_STRUCTURE);
      this.board = cache.get(CONST.SYSTEM_DB_BOARD);
      this.route = cache.get(CONST.SYSTEM_DB_ROUTE);
      this.initialized = true;
      this.bind();
    }
docs: 初始化，缓存board，structure，route数据