private DeactivatedContainer activateContainer(ContainerBuilder builder, Runnable onPreviousContainerTermination) {
        DeactivatedContainer deactivated = activator.activateContainer(builder);
        if (deactivated != null) {
            nonTerminatedContainerTracker.register();
            deactivated.notifyTermination(() -> {
                try {
                    onPreviousContainerTermination.run();
                } finally {
                    nonTerminatedContainerTracker.arriveAndDeregister();
                }
            });
        }
        return deactivated;
    }
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