@Override
    public void notifyTopicUnsubscribed(final String topic, final String clientID, final String username) {
        for (final InterceptHandler handler : this.handlers.get(InterceptUnsubscribeMessage.class)) {
            LOG.debug("Notifying MQTT UNSUBSCRIBE message to interceptor. CId={}, topic={}, interceptorId={}", clientID,
                topic, handler.getID());
            executor.execute(() -> handler.onUnsubscribe(new InterceptUnsubscribeMessage(topic, clientID, username)));
        }
    }
@Test
    public void testNotifyTopicUnsubscribed() throws Exception {
        interceptor.notifyTopicUnsubscribed("o2", "cli1234", "cli1234");
        interval();
        assertEquals(80, n.get());
    }