A Web Application aRchive (WAR) file contains a packaged Java Web application.
WAR files can be used to import a Web application into a Web server. A Web application is a group of HTML pages, JSP pages, servlets, resources and source file, which can be managed as a single unit.
In addition to project resources, the WAR file includes a Web deployment descriptor file. The Web deployment descriptor is an XML file that contains deployment information, MIME types, session configuration details, and other settings for a Web application. The Web deployment descriptor file (web.xml) provides information about the WAR file is shared with the developers, assemblers, and deployers in a JEE environment.
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