private Integer nodeFor(ConfigResource resource) {
        if ((resource.type() == ConfigResource.Type.BROKER && !resource.isDefault())
                || resource.type() == ConfigResource.Type.BROKER_LOGGER) {
            return Integer.valueOf(resource.name());
        } else {
            return null;
        }
    }
Returns the broker id pertaining to the given resource, or null if the resource is not associated
with a particular broker.
clients/src/main/java/org/apache/kafka/clients/admin/KafkaAdminClient.java