Sun GlassFish Enterprise Server v3 Application Deployment Guide

Deployment Descriptors and Annotations

A deployment descriptor is an XML file that describes how a Java EE application or module should be deployed. Each deployment descriptor XML file has a corresponding Document Type Definition (DTD) file or schema (XSD) file, which defines the elements, data, and attributes that the deployment descriptor file can contain. The deployment descriptor directs a deployment tool to deploy a module or application with specific container options, and also describes specific configuration requirements that you must resolve.

Because the information in a deployment descriptor is declarative, it can be changed without requiring modifications to source code. At run time, Enterprise Server reads the information in the deployment descriptor and deploys the application or module as directed.

The following types of deployment descriptors are associated with Enterprise Server:

An annotation, also called metadata, enables a declarative style of programming. You can specify information within a class file by using annotations. When the application or module is deployed, the information can either be used or overridden by the deployment descriptor. Enterprise Server supports annotation according to the following specifications:

The following annotation and deployment descriptor combinations are supported: