var Graph = function (directed) {
    /**
     * 是否是有向图
     * @type {boolean}
     * @private
     */
    this._directed = directed || false;

    /**
     * @type {Array.<module:echarts/data/Graph.Node>}
     * @readOnly
     */
    this.nodes = [];

    /**
     * @type {Array.<module:echarts/data/Graph.Edge>}
     * @readOnly
     */
    this.edges = [];

    /**
     * @type {Object.<string, module:echarts/data/Graph.Node>}
     * @private
     */
    this._nodesMap = {};
    /**
     * @type {Object.<string, module:echarts/data/Graph.Edge>}
     * @private
     */
    this._edgesMap = {};

    /**
     * @type {module:echarts/data/List}
     * @readOnly
     */
    this.data;

    /**
     * @type {module:echarts/data/List}
     * @readOnly
     */
    this.edgeData;
};