Chapter 10: Servlet Debugging Techniques

---

Overview

In this chapter we'll look at how to get hold of information that tells us what's going on inside the servlet container at run time. We'll cover three different techniques: using filters, using event listeners, and finally using the Java Platform Debugger Architecture (JPDA), which although not part of the Servlet API is useful and interesting nonetheless.

Specifically, we'll cover:

• Some of the problems associated with servlet development that make debugging important

• Using servlet filters and event listeners as non-invasive plug-in components to debug any web application

• The Java Platform Debugger Architecture.

• Visualizing our debugger results

• Using the J2SE 1.4 Logging API to create a flexible debugging architecture

• The prospect of a novel runtime reverse-engineering tool for UML

We won't go over old ground in this chapter so the coverage of filters and event listeners will be kept relevant to the task at hand.

---