JavaScript 实现类似Java Map对象

!(function (window) {    /**     * Map对象构造函数     * @class     * @constructor     */    var Map = function () {        /**         * 存档所有Key值的数组对象         * @type {any[]|Array}         */        this.keys = new Array();        /**         * 存放数据对象         * @type {Object}         */        this.values = new Object;    }    /**     * 扩充Map对象方法     * @type {{}}     */    Map.prototype = {        /**         * 存放键值对         * @function         * @param key         * @param value         */        put: function (key, value) {            if (!this.values[key])                this.keys.push(key);            this.values[key] = value;        },        /**         * 根据key值获取对象         * @param key         * @returns {*}         */        get: function (key) {            return this.values[key];        },        /**         * 根据key值删除对象         * @param key         */        remove: function (key) {            this.keys.remove(key);            this.values[key] = null;        },        /**         * 循环遍历，执行回调函数         * @param fn 回调函数         */        each: function (fn) {            if (typeof fn != 'function') {                return;            }            for (var i = 0, var len = this.keys.length;            i < len;            i++            )            {                var k = this.keys[i];                fn(k, this.values[k], i);            }        },        /**         * 获取键值数组(类似Java的entrySet())         * @return 键值对象{key,value}的数组         */        entrys: function () {            var len = this.keys.length;            var entrys = new Array(len);            for (var i = 0; i < len; i++) {                entrys[i] = {                    key: this.keys[i],                    value: this.values[i]                };            }            return entrys;        },        /**         * 判断Map是否为空         */        isEmpty: function () {            return this.keys.length == 0;        },        /**         * 获取键值对数量         */        size: function () {            return this.keys.length;        },        /**         * 重写toString         */        toString: function () {            var s = "{";            for (var i = 0; i < this.keys.length; i++, s += ',') {                var k = this.keys[i];                s += k + "=" + this.values[k];            }            s += "}";            return s;        }    }    window.Map = Map;})(window);//创建Map对象var map = new Map();map.put("obj", "String");map.get("obj");...