DirectMessageListenerContainer's default TaskScheduler is not shut down when container gets destroyed

[sherter]

The default ThreadPoolTaskScheduler created in DirectMessageListenerContainer#doInitialize does not get shut down when the container is destroy()ed. The scheduler's non-daemon threads prevent the app from shutting down cleanly in that case. This doesn't happen when using (the default) "simple" message listener container:

@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        ConfigurableApplicationContext context = new SpringApplicationBuilder()
                .properties("spring.rabbitmq.listener.type=direct")
                .sources(DemoApplication.class)
                .run(args);
        context.close();
        // process does not exit after calling close because DirectMessageListenerContainer#destroy
        // does not call taskScheduler.shutdown() and the scheduler's non-daemon threads keep the process alive
    }

    @Bean
    public ApplicationRunner runner(AmqpTemplate template) {
        return args -> template.convertAndSend("myqueue", "foo");
    }

    @Bean
    public Queue myQueue() {
        return new Queue("myqueue");
    }

    @RabbitListener(queues = "myqueue")
    public void listen(String in) {
        System.out.println(in);
    }
}

Expected behavior
The process should stop after calling context.close().

Version
3.4.5

[artembilan]

Confirmed as a bug.
The DirectMessageListenerContainer has a logic like this:

@Override
	protected void doStop() {
		super.doStop();
		if (!this.taskSchedulerSet && this.taskScheduler != null) {
			((ThreadPoolTaskScheduler) this.taskScheduler).shutdown();
			this.taskScheduler = null;
		}
	}

However, this one is not called from the context.close(); flow.
This one leads to the AbstractMessageListenerContainer:

@Override
	public void stop(Runnable callback) {
		shutdown(callback);
	}

And that shutdown() doesn't call mentioned doStop().

[artembilan]

Fixed via: e210c97