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The Geronimo-specific deployment plan for an EJB application, which is usually packaged as an EJB JAR file, is called "openejb-jar.xml". The openejb-jar.xml deployment plan is used (in conjunction with the ejb-jar.xml Java EE deployment plan) to deploy enterprise applications to the Geronimo application server. The openejb-jar.xml deployment plan is an optional file, but is typically used when deploying a EJB JAR file. It is used to map roles and resources (e.g., security roles, EJB names, database resources, JMS resources, etc.) declared in the openejb-jar.xml deployment plan to corresponding entities deployed in the server. Also, if there are any EJB container-specific configurations required those setting are configured in this deployment plan as well. If the EJB module depends on any third party libraries or other services running in the server, all these third party libraries and the services are specified in the openejb-jar.xml file. Some EJB applications require class loading requirements different from the default class loading behavior. The openejb-jar.xml file allows the application deployer to configure this as well. There are many more configurations that could be done through the openejb-jar.xml file depending on the requirements of the EJB application.
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