JS设计模式源代码

				var Book = function(newIsbn, newTitle, newAuthor) { // implements Publication								  // Private attributes.				  var isbn, title, author;								  // Private method.				  function checkIsbn(isbn) {				    ... 				  }  								  // Privileged methods.				  this.getIsbn = function() {				    return isbn;				  };				  this.setIsbn = function(newIsbn) {				    if(!checkIsbn(newIsbn)) throw new Error('Book: Invalid ISBN.');				    isbn = newIsbn;				  };								  this.getTitle = function() {				    return title;				  };				  this.setTitle = function(newTitle) {				    title = newTitle || 'No title specified';				  };								  this.getAuthor = function() {				    return author;				  };				  this.setAuthor = function(newAuthor) {				    author = newAuthor || 'No author specified';				  };								  // Constructor code.				  this.setIsbn(newIsbn);				  this.setTitle(newTitle);				  this.setAuthor(newAuthor);				};								// Public, non-privileged methods.				Book.prototype = {				  display: function() {				    ...				  }				};