public static BundleInstantiationSpecification build(Element spec) {
        ComponentSpecification id = XmlHelper.getIdRef(spec);
        ComponentSpecification classId = getComponentSpecification(spec, "class");
        ComponentSpecification bundle = getComponentSpecification(spec, "bundle");

        BundleInstantiationSpecification instSpec = new BundleInstantiationSpecification(id, classId, bundle);
        validate(instSpec);

        return bundle == null ? setBundleForComponent(instSpec) : instSpec;
    }
This object builds a bundle instantiation spec from an XML element.

@author gjoranv
config-model/src/main/java/com/yahoo/vespa/model/container/xml/BundleInstantiationSpecificationBuilder.java