Now let's take a close look at all of the modules that comprise the course.

Module 1: Managing Web Sessions
This module begins with a good overview of the various ways Web developers are able to maintain state information in Web applications. It then discusses how to use an HttpSession object store, and retrieve user session data contained in Java objects like Strings and Vectors. If you're already familiar with Java Beans, this technique may seem dated, but it does serve as a useful "first step" to those who are unfamiliar with J2EE programming techniques in general.

This module also discusses URL rewriting, as well as how to implement it in WebSphere. If you're unfamiliar with this technique, URL rewriting is typically necessary in those circumstances when you have no control over the browser configuration of users who access your Web application. This is typically true for extranet applications.

The first activity in this module shows you how to import the three EAR files, used by the demos and activities, into your workspace. The remaining activities are straightforward and shouldn't require much time to complete, except for the last activity. The last activity requires you to add code to a simple shopping cart application. Of all the activities in the course, this one took me the most time to complete, due to the conditional logic that you'll be required to implement.

Module 2: Servlet Processing
This module focuses exclusively on servlet programming techniques, including Exception handling, throwing Exceptions, accessing inner and external classes, implementing the SingleThreadModel, and using servlet initialization parameters.

The discussion of the servlet life cycle is concise and easy to follow. Also, the discussion of the scope of variables in servlets was very well written. The last thing you want to do is discover that a servlet you've written is behaving strangely because you've improperly declared variables at the class level.

One technique discussed in this module I'm glad I learned about is how to configure the Web Deployment Descriptor (Web.xml) to display a specific error page when specific error codes, like 404, or Java Exception types, like java.lang.ClassNotFoundException, are encountered, like in Figure F.

FIGURE F


The Pages tab of the Web Deployment Descriptor can be configured to handle specific error codes or Java Exceptions. Roll over picture for a larger image.

All of the activities in this module can be completed without much difficulty. The last activity, which involves adding error handling to a simple shopping cart application, is a bit more challenging than the rest, though.

Module 3: JSP Programming
This module is an excellent introduction to JSP programming. The topics discussed here are roughly the same as those discussed in Module 2, except that they're geared towards JSPs instead of servlets.

One part of this module that I wasn't too fond of was the lesson on processing a JSP using another JSP. This amounts to server-side validation, which I've learned over several years of Domino application development not to do because of performance considerations.