class BrokerInterceptor implements Interceptor {

    @Override
    public void notifyTopicSubscribed(final Subscription sub, final String username) {
        for (final InterceptHandler handler : this.handlers.get(InterceptSubscribeMessage.class)) {
            LOG.debug("Notifying MQTT SUBSCRIBE message to interceptor. CId={}, topicFilter={}, interceptorId={}",
                sub.getClientId(), sub.getTopicFilter(), handler.getID());
            executor.execute(() -> handler.onSubscribe(new InterceptSubscribeMessage(sub, username)));
        }
    }

    private  BrokerInterceptor(int poolSize, List<InterceptHandler> handlers);
      BrokerInterceptor(List<InterceptHandler> handlers);
      BrokerInterceptor(IConfig props, List<InterceptHandler> handlers);

}