The Web deployment descriptor is an XML file, called web.XML. It is generated in the WEB-INF directory and is independent from the application server.
The Web application deployment descriptor is generated per package. A WAR command available in the Tasks page of the Generation dialog box allows you to build a Web Archive that contains the Web deployment descriptor, in addition to all classes and file objects referenced by JSP components. At the model level, an EAR command is also provided to group all WAR and JAR files generated for a given model inside a single enterprise archive. The EAR contains an additional deployment descriptor generated per model that is called application.XML.
The Web deployment descriptor is available from the Preview page of the package, or the model property sheet.