Before JCA 1.6, this metadata was specified only in the deployment descriptor, but now you can specify this metadata using either a deployment descriptor or annotations. Metadata that is specified in annotations is merged into the deployment descriptor of a RAR module when it is updated, if the module is not marked metadata-complete in the deployment descriptor and if the module version is 1.6 or later.
The metadata-complete element defines whether the deployment descriptor for the resource adapter module is complete or whether the class files that are available to the module and packaged with the resource adapter should be examined for annotations that specify deployment information. If the metadata-complete is set to true, the application server deployment tool must ignore any annotations that specify deployment information, which might be present in the class files of the application. If metadata-complete is not specified, or is set to false, the deployment tool must examine the class files of the application for annotations, as specified by the JCA 1.6 Specification. If the deployment descriptor is not included, or is included but not marked metadata-complete, the deployment tool processes annotations.
Application servers must assume that metadata-complete is true for resource adapter modules with deployment descriptors that meet the requirements of JCA specification 1.5 and earlier. For a complete list of the supported annotations and their usage, consult the JCA specification.