Recursive static methods in ExtJS 4

Util.js

Ext.define('Util', {


    config: {},

    constructor: function () {},

    /**
     * Returns a string with the object properties and values. Could be static
     * @param {Object} obj
     * @param {String} tabs
     */
    objectToString: function (obj, tabs) {

        var stringObj = '';
        var me = this;
        var objType = APP.lib.Util.getClass(obj);

        if (objType == 'Array') {
            Ext.each(obj, function (elem, index, objArray) {
                if (Object.prototype.toString.call(elem).slice(8, -1) == 'Object') stringObj += me.objectToString(elem, tabs + '\t')

                else if (Object.prototype.toString.call(elem).slice(8, -1) == 'Array') Ext.each(elem, function (item, index, array) {
                    stringObj += me.objectToString(item, tabs + '\t');
                })

                else
                // console.log(tabs + key + ' -> ' + obj[key]+'\n');
                stringObj += tabs + key + ' -> ' + obj[key] + '\n'

            })
        } else if (objType == 'Object') {
            for (var key in obj) {
                if (Object.prototype.toString.call(obj[key]).slice(8, -1) == 'Object') stringObj += me.objectToString(obj[key], tabs + '\t')

                else if (Object.prototype.toString.call(obj[key]).slice(8, -1) == 'Array') Ext.each(obj[key], function (elem, index, array) {
                    stringObj += me.objectToString(elem, tabs + '\t');
                })

                else
                // console.log(tabs + key + ' -> ' + obj[key]+'\n');
                stringObj += tabs + key + ' -> ' + obj[key] + '\n'
            }
        }

        return stringObj;
    },

    statics: {
        /**
         * Returns the class/type of obj based as a call to the toString method on
         * obj
         * @param {Object|String|Number|Array} obj any javascript object
         */
        getClass: function (obj) {
            var clas = Object.prototype.toString.call(obj).slice(8, -1);
            return clas;
        },


        isClassOf: function (obj, type) {
            var clas = Object.prototype.toString.call(obj).slice(8, -1);
            return obj !== undefined && obj !== null && clas === type;
        },


        objToString: function (obj, tabs) {
            var stringObj = '';
            var objType = APP.lib.Util.getClass(obj);

            if (objType == 'Array') {
                Ext.each(obj, function (elem, index, objArray) {
                    if (Object.prototype.toString.call(elem).slice(8, -1) == 'Object') stringObj += APP.lib.Util.objToString(elem, tabs + '\t')

                    else if (Object.prototype.toString.call(elem).slice(8, -1) == 'Array') Ext.each(elem, function (item, index, array) {
                        stringObj += APP.lib.Util.objToString(item, tabs + '\t');
                    })

                    else
                    // console.log(tabs + key + ' -> ' + obj[key]+'\n');
                    stringObj += tabs + key + ' -> ' + obj[key] + '\n'

                })
            } else if (objType == 'Object') {

                for (var key in obj) {
                    if (Object.prototype.toString.call(obj[key]).slice(8, -1) == 'Object') stringObj += APP.lib.Util.objToString(obj[key], tabs + '\t')

                    else if (Object.prototype.toString.call(obj[key]).slice(8, -1) == 'Array') Ext.each(obj[key], function (elem, index, array) {
                        stringObj += APP.lib.Util.objToString(elem, tabs + '\t');
                    })

                    else
                    // console.log(tabs + key + ' -> ' + obj[key]+'\n');
                    stringObj += tabs + key + ' -> ' + obj[key] + '\n'
                }
            }
            return stringObj;
        },


        clone: function (obj) {
            if (obj === null || typeof obj !== 'object') {
                return obj; // return obj if obj is a Number, String, Boolean, ...
            }

            var temp = obj.constructor(); // give temp the original obj's constructor
            for (var key in obj) {
                temp[key] = this.clone(obj[key]);
            }

            return temp;
        }

    } // EO statics

}); // EO class


var myObj = {
    name: 'Lebron',
    lastname: 'Bryant',
    teams: ['Cle', 'LAL', 'Heat']
}

console.log(myObj.name);

var clonObj = Util.clone(myObj);
clonObj.name = 'Steve';

console.log(myObj.name);
console.log(clonObj.name);
clonObj.teams.push('Utah');

console.log(myObj.name);
console.log(clonObj.name);

console.log('Teams');
Ext.each(clonObj.teams, function (team, index, teamSet) {
    console.log (myObj.teams[index]+' vs '+clonObj.teams[index]);
});