javascript pattern with jquery

my-module.js

var myModule = (function($, window) {
    // private property
    var myProp = "hello";
    // private methods
    function myPrivateMethod() {
        alert($('*').length);
    };
    // public methods
    return {
        init: function() {
            alert(myProp);
            myProp = "Goodbye";
        },
        myPublicMethod: function() {
            alert('public method');
        },
        myPublicMethod2: function() {
            myPrivateMethod();
            alert(window.Object);
            alert(myProp);
        }
    };
})($, window);

myModule.init();
myModule.myPublicMethod();
myModule.myPublicMethod2();

my-object.js

;(function(window) {
   var Book = function( id, title, author, genre, pageCount,publisherID, ISBN, checkoutDate, checkoutMember, dueReturnDate,availability ){
 
   this.id = id;
   this.title = title;
   this.author = author;
   this.genre = genre;
   this.pageCount = pageCount;
   this.publisherID = publisherID;
   this.ISBN = ISBN;
   this.checkoutDate = checkoutDate;
   this.checkoutMember = checkoutMember;
   this.dueReturnDate = dueReturnDate;
   this.availability = availability;
 
};
 
Book.prototype = {
 
  getTitle: function () {
     return this.title;
  },
 
  getAuthor: function () {
     return this.author;
  },
 
  getISBN: function (){
     return this.ISBN;
  },
 
  // For brevity, other getters are not shown
  updateCheckoutStatus: function( bookID, newStatus, checkoutDate , checkoutMember, newReturnDate ){
 
     this.id  = bookID;
     this.availability = newStatus;
     this.checkoutDate = checkoutDate;
     this.checkoutMember = checkoutMember;
     this.dueReturnDate = newReturnDate;
 
  },
 
  extendCheckoutPeriod: function( bookID, newReturnDate ){
 
      this.id =  bookID;
      this.dueReturnDate = newReturnDate;
 
  },
 
  isPastDue: function(bookID){
 
     var currentDate = new Date();
     return currentDate.getTime() > Date.parse( this.dueReturnDate );
 
   }
};

window.Book = Book;

})(window);

var book = new Book(21, "a book title");
alert(book.getTitle());