The entire Struts framework now relies on the Commons Logging library, which is an open source logging API from Jakarta. It provides a simple, consistent logging API that can be used within all applications and that allows different implementations to be plugged in dynamically. You will need the Commons Logging JARs, but these should already be included with the Struts framework. This change also required some configuration settings to be added. Chapter 15 covers the Commons Logging library as well as general logging in a Struts application.