@Override
    public long size() {
        val filter = Predicates.not(Predicates.instanceOf(ImmutableServiceRegistry.class));
        return serviceRegistries.stream()
            .filter(filter)
            .map(ServiceRegistry::size)
            .mapToLong(Long::longValue)
            .sum();
    }
This is {@link DefaultChainingServiceRegistry}.

@author Misagh Moayyed
@since 5.3.0
core/cas-server-core-services-registry/src/main/java/org/apereo/cas/services/DefaultChainingServiceRegistry.java