private <T extends ConfigInstance> T getConfig(Class<T> configClass) {
        Subscriber subscriber = subscriberFactory.getSubscriber(Collections.singleton(new ConfigKey<>(configClass, configId)),
                                                                configClass.getName());
        try {
            subscriber.waitNextGeneration(true);
            return configClass.cast(first(subscriber.config().values()));
        } finally {
            subscriber.close();
        }
    }
Do not delete this method even if it's empty.
Calling this methods forces this class to be loaded,
which runs the static block.
container-disc/src/main/java/com/yahoo/container/jdisc/ConfiguredApplication.java