A custom resource accesses a local JNDI repository. The customresource element defined in server.xml provides a way of specifying a custom server-wide resource object factory. Such object factories implement the javax.naming.spi.ObjectFactory interface. This element associates a JNDI name (specified through the jndiname sub-element like other Sun Java System Web Server resources) to be used in the server-wide namespace, its type, name of the resource factory class and a set of standard properties used to instantiate the same.
You need to ensure that the resource reference’s environment references are linked to the configured server-wide resources defined using the customresource and externaljndiresource tags in server.xml. Dynamic redeployment of application components is an issue for the JNDI naming environment. Sun Java System Web Server will release all the application specific references and rebind all the new references into the newly installed application’s naming context.
For information on creating a custom resource, see Creating Custom Resources.