JavaScriptFactory

(function(){
    window.onload = function(e){
        // creates objects. it looks like a constructor but it is not, because we don't use new to create objects.
        // As Duglas Crocford says "I don't use new anymore"
        // it creates persons
        var myFactory = function(name, age){
            return { // this is object representing a Person
                // 1. properties of the object. We can change them without problems. Not good.
//-             name: name, // property (create as a field/instance variable)
//-             age: age, // property (create as a field/instance variable)
                // 2. Only getters no setters
                // if you want to make it only for read you have to use getter without setter (accessor without mutator)
                getName: function(){ return name; }, // in this case we will not need the instance variables name and age
                getAge: function(){ return age; }, // in this case we will not need the instance variables name and age

                intorduceYourSelf: function(){ // closure. name and age are free variables from the outer context
                    // 1. using directly the free variables
                    //- return "My name is " + name + ". And I am " + age + " old.";
                    // or I can use the properties
                    // 2. using the fields (instance variables)
                    //- return "My name is " + this.name + ". And I am " + this.age + " old.";
                    // 3. Using the accessors
                    return "My name is " + this.getName() + ". And I am " + this.getAge() + " old.";
                }
            };
        };

        // use the factory to produce 2 objects of class person
        var stoyan = myFactory("Stoyan", 52);
        // create another object of the same class (Person)
        var ivan = myFactory("Ivan", 34);

        // let's test what was produced
        alert(stoyan.intorduceYourSelf()); // The result is: "My name is Stoyan. And I am 52 old."
        alert(ivan.intorduceYourSelf());    // The result is: "My name is Ivan. And I am 34 old."
    }
})();