Ajax for Web Application Developers

An Overview of the Singleton Pattern

Imagine having a large-scale Ajax application with dozens of objects. In this application, you would like to add an object that handles all your Ajax updates. We will call this object the AjaxUpdater. All the objects in your web application will communicate through this object if they need to make an XHR at any time. Not only will this object handle all the requests, it will also handle delegating the responses to specified callback methods. In other words, when the response has been received, the AjaxUpdater will notify the requesting object if a callback method was specified during the request. This situation would require the use of the Singleton pattern because we would need a consistent object reference ...