public long getMsgOutCounter() {
        return msgOutFromRemovedConsumer.longValue() + sumConsumers(Consumer::getMsgOutCounter);
    }
@Test
    public void testGetMsgOutCounter() {
        subscription.msgOutFromRemovedConsumer.add(1L);
        when(consumer.getMsgOutCounter()).thenReturn(2L);
        assertEquals(subscription.getMsgOutCounter(), 3L);
    }