private static ComponentSpecification getComponentSpecification(Element spec, String attributeName) {
        return (spec.hasAttribute(attributeName)) ?
                new ComponentSpecification(spec.getAttribute(attributeName)) :
                null;
    }
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