@Override
        public Map<ConfigKey<ConfigInstance>, ConfigInstance> config() {
            Map<ConfigKey<ConfigInstance>, ConfigInstance> ret = new HashMap<>();
            for (ConfigKey<ConfigInstance> key : configKeys) {
                ConfigInstance.Builder builder = root.getConfig(newBuilderInstance(key), key.getConfigId());
                if (builder == null)
                    throw new RuntimeException("Invalid config id " + key.getConfigId());
                ret.put(key, newConfigInstance(builder));
            }
            return ret;
        }
@author Tony Vaagenes
@author gjoranv
@author ollivir
standalone-container/src/main/java/com/yahoo/container/standalone/StandaloneSubscriberFactory.java