Programming Jakarta Struts, Second Edition

Configuring the web.xml File for Struts

Although the web.xml file is used for configuring any generic web application, there are a few Struts-specific configuration options that you must configure within this file when using the Struts framework. The next section describes the necessary steps that you’ll need to perform to ensure that your Struts application is properly configured.

Mapping the Struts ActionServlet

The first and perhaps most important step that you need to perform is to configure the ActionServlet that will receive all incoming requests for the application.

Tip

You need to configure only a single ActionServlet, regardless of the number of application modules that are being used. Some developers choose to set up multiple controller servlets to handle different functional areas of the application. Because servlets are multithreaded, you don’t gain any real performance or scalability value by using multiple ActionServlet mappings.

There are two steps in configuring the Struts controller servlet in the web.xml file. The first step is to use the servlet element to configure the servlet instance that can later be mapped in the servlet-mapping element. The child elements that can be used in the servlet element are shown here:

<!ELEMENT servlet (icon?, servlet-name, display-name?, description?,
   (servlet-class|jsp-file), init-param*, load-on-startup?, run-
   as?, security-role-ref*)
>

The child elements that we are most interested in are servlet-name, servlet-class, and ...