Configuring deployment with the web.xml file

In the WEB-INF folder of a web project, there is usually a file named web.xml. It was mandatory before the @WebServlet annotation was introduced. With the annotation, the application server can determine on its own which files are servlets and which are not. There is more that you can do in this file than just list servlets. For this reason, I advise you to always have a web.xml file.

Our descriptor will be quite basic:

<web-app xmlns="https://jakarta.ee/xml/ns/jakartaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation=
                 "https://jakarta.ee/xml/ns/jakartaee
       https://jakarta.ee/xml/ns/jakartaee/web-app_5_0.xsd"
       version="5.0"&gt...