code: function MongoStore(options) {
                  if (typeof options === "undefined") { options = {
                  }; }
                          _super.call(this);
                  this._logger = shared.utils.defaultLogger();
                  // Database stuff
                  this._collection = null;
                  this._pending = [];
                  // Outstanding work queue
                  this._root = null;
                  // Root object
                  this._cache = new shared.mtx.ObjectCache();
                  this._host = options.host || 'localhost';
                  this._port = options.port || 27017;
                  this._dbName = options.db || 'shared';
                  this._collectionName = options.collection || 'shared';
                  this._safe = options.safe || 'false';
                  this._logger.debug('STORE', '%s: Store created', this.id());
              }
docs: For checking for lock changes