@Override
    public void addModelListener(final CreatingListener listener) throws StorageException {
        listeners.add(listener);
        for (Model model : models) {
            listener.whenCreating(model);
        }
    }
CreatingListener listener could react when {@link ModelCreator#add(Class, int, Storage)} model happens. Also, the
added models are being notified in this add operation.
oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/storage/model/StorageModels.java