Sun OpenSSO Enterprise 8.0 Developer's Guide

Overview of WAR Files in Java EE Software Development

OpenSSO Enterprise is built on the Java EE platform, which uses a component model to create full-scale applications. A component is self-contained functional software code assembled with other components into a Java EE application. The Java EE application components can be deployed separately on different servers. Java EE application components include the following:

Web Components

When a web browser executes a Java EE application, it deploys server-side objects known as web components. JSP and corresponding servlets are two such web components.


Small Java programs that dynamically process requests and construct responses from a web browser. Servlets run within web containers.

Java Server Pages (JSPs)

Text-based documents that contain static template data such as HTML, Scalable Vector Graphics (SVG), Wireless Markup Language (WML), or eXtensible Markup Language (XML). JSPs also contain elements such as servlets that construct dynamic content.

How Web Components are Packaged

Java EE components are usually packaged separately, and then bundled together into an Enterprise Archive (EAR) file for application deployment. Web components are packaged in WAR files. Each WAR file contains servlets, JSPs, a deployment descriptor, and related resource files.

Static HTML files and JSP are stored at the top level of the WAR directory. The top-level directory contains the WEB-INF subdirectory which contains tag library descriptor files in addition to the following:

Server-side classes

Servlets, JavaBean components and related Java class files. These must be stored in the WEB-INF/classes directory.

Auxiliary JARs

Tag libraries and any utility libraries called by server-side classes. These must be stored in the WEB-INF/lib directory.


The web component deployment descriptor is stored in the WEB-INF directory