Is it ok to call AbstractMessageListenerContainer#stop() multiple times?

[matijabruncic]

I'm looking at implementations of this class and it seems to me that both implementations are safe to call multiple times.

spring-kafka/spring-kafka/src/main/java/org/springframework/kafka/listener/ConcurrentMessageListenerContainer.java

Line 174 in a9fc833

protected void doStop(final Runnable callback) {

spring-kafka/spring-kafka/src/main/java/org/springframework/kafka/listener/KafkaMessageListenerContainer.java

Line 215 in a9fc833

protected void doStop(final Runnable callback) {

If we call AbstractMessageListenerContainer#stop() once it will stop containers, but if we call it second time(or multiple times) it will wait until timeout (10 sec by default).

Should this be considered as a bug?

[garyrussell]

Yes; this is a bug; the second (and subsequent) stop() should exit immediately.