e-business Technologies  «Prev  Next»

Lesson 10 e-Business enhancement technologies
Objective Discuss the influence of XML, JavaScript, and EJB.

ebusiness Enhancement Technologies

HTML vs. XML: What is the difference?
XML, JavaScript, and Java EE are important technologies that allow a company to enhance its Web site and provide dynamic content over the Web.
XML stands for eXtensible Markup Language and is a specification that allows designers to create their own customized tags to provide functionality not available within HTML. For example, XML allows a link to point to and ultimately combine multiple documents for presentation in the Web browser. This is in contrast to HTML's limited functionality of only linking to one document.
The following XML course on XML Programming contains fundamental information with respect to XML

JavaScript

JavaScript is a quicker and simpler language than CGI[1]. For example, many HTML pages that contain forms use a CGI program to process the form's data once it is submitted. JavaScript interacts with HTML source code, enabling Web authors to spice up their sites with dynamic content. Note, Javascript is often confused with Java. These two should not be confused; JavaScript is a scripting language, where Java is a full-fledged programming language.
Question: What can you do with JavaScript?
JavaScript can be used to enhance interactivity and functionality of Web pages. Some of the features of JavaScript include:

  1. Images that change when you position the mouse over them
  2. Altering preference capability that helps manage the user's browsing environment
  3. Pre-screening data contained in HTML forms
  4. User interaction flags such as prompts, confirmation, and warning messages

Enterprise JavaBeans (EJB)

JavaBeans are pre-packaged bundles of common functions based on a standard, component-based architecture. This architecture provides re-use of application logic, improved Internet application performance and the ability to distribute applications across an enterprise through the extended environment defined by the Enterprise JavaBean standard. JavaBeans offer the key functionality of providing server-side functionality that the client browser does not need to fetch. For example, to run an application through your Web browser, you may need to download a plug-in. With EJB, the plug-in [2] is not needed because it is stored on and utilized directly on the server.
EJB is a component-based architecture that provides for distribution of applications across an enterprise, re-use of application logic, and higher performance. More on this subject can be read at EJB Architecture

E-Business Example

A developer puts a market calculator application on a server for client use. A client (user) then accesses the calculator for use. In a non-EJB world the client would need to download a plug-in prior to running the application.
With EJB, the server would know instantly that the client does not have the correct functionality and would deliver it seamlessly without the user knowing it. Another advantage is that EJB splits processing power, so that the both the client and the server use some of its calculation power to optimize performance.

(JSON) JavaScript Object Notation

JSON is simply a data-interchange format and, therefore, does not directly require immediate knowledge of the JavaScript language. However, this book does not only discuss the composition of JSON. It also discusses how to incorporate it within an application. For this reason, this book employs JavaScript extensively to demonstrate the many ways to work with JSON. There are plenty of great books that reveal the ins and outs of the JavaScript language. This chapter solely acts as a primer to the upcoming chapters.
The JavaScript Object Notation data format, or JSON for short, is derived from the literals of the JavaScript programming language. This makes JSON a subset of the JavaScript language. As a subset, JSON does not possess any additional features that the JavaScript language itself does not already possess. Although JSON is a subset of a programming language, it itself is not a programming language but, in fact, a data interchange format.
JSON is known as the data interchange standard, which subtextually implies that it can be used as the data format wherever the exchange of data occurs. A data exchange can occur between both browser and server and even server to server, for that matter. Of course, these are not the only possible means to exchange JSON, and to leave it at those two would be rather limiting.
[1] CGI:: Common Gateway Interface. CGI programs are the most common way for Web servers to interact dynamically with users.
[2] Plug-in:: A file with data used to alter, enhance, or extend the operation of a parent application program; a plug-in adds functionality that might not exist without it.