Chapter 7 Developing Applications with PowerJ and EAServer

Working with deployment descriptors

A deployment descriptor, as defined by the J2EE specification, is an XML file provided with each component or J2EE application. The XML file contains all the information required by the application or component for deployment to the server. For example, an EJB 1.1 deployment descriptor includes the structural information related to the enterprise bean and declares all the bean's external dependencies so the container knows how to deploy the bean.

When you use a PowerJ wizard to create a component (EJB, JSP, or servlet) or a J2EE archive file (WAR or EAR), the deployment descriptor is automatically created. The deployment descriptor contains two kinds of information:

Mandatory and usually unchangeable structural information that describes the structure of a component and declares external dependencies
Optional and changeable application assembly information that describes how the components are composed into a larger application deployment unit

You can modify the application assembly information in PowerJ's Workspace view.