write the descriptor class to a DOM tree and return it
if (! (descriptor instanceof RoleReference)) {
throw new IllegalArgumentException(getClass() + " cannot handles descriptors of type " + descriptor.getClass());
}
RoleReference roleRef = (RoleReference) descriptor;
Node subNode = super.writeDescriptor(parent, nodeName, roleRef);
writeLocalizedDescriptions(subNode, descriptor);
appendTextChild(subNode, EjbTagNames.ROLE_NAME, roleRef.getName());
appendTextChild(subNode, EjbTagNames.ROLE_LINK, roleRef.getValue());
return subNode;