@Override
    public ContainerSnapshot newReference(URI uri, Object context) {
        ActiveContainer container = containerRef.get();
        if (container == null) {
            throw new ContainerNotReadyException();
        }
        return container.newReference(uri, context);
    }
@author Simon Thoresen Hult
@author bjorncs
jdisc_core/src/main/java/com/yahoo/jdisc/core/ApplicationLoader.java