Support multiple TaskDecorator beans

[mhalbritter]

In #43190 (landed in 3.5.0-M1), support for TaskDecorator has been added. If a bean is in the context, it's automatically applied to SimpleAsyncTaskExecutorBuilder and ThreadPoolTaskExecutorBuilder.

However, if there are multiple TaskDecorator beans are in the context, none is applied. That's because we use .getIfUnique.

I think that's somewhat confusing. It would be better to fail if there is more than one bean, or even better, support multiple TaskDecorators (maybe using composition?).

[mhalbritter]

Not sure if this is an enhancement or a bug.

[nosan]

In #43190 (landed in 3.5.0-M1), support for TaskDecorator has been added. If a bean is in the context, it is automatically applied to SimpleAsyncTaskExecutorBuilder and ThreadPoolTaskExecutorBuilder.

#43190 was specifically about scheduled tasks 😃

However, if there are multiple TaskDecorator beans in the context, none of them are applied. This is because .getIfUnique is used.

This logic has existed from the very beginning: #1563

I think that's somewhat confusing. It would be better to fail if there is more than one bean, or even better, support multiple TaskDecorator instances (perhaps using composition?).

I believe composition is a good idea. The org.springframework.core.task.support.CompositeTaskDecorator can be used.

Not sure if this is an enhancement or a bug.

I think this is an enhancement

[mhalbritter]

Oh, sorry @nosan I mixed things up. Thanks for digging.

[nosan]

@mhalbritter

Could you kindly assign this one to me, please?

[snicoll]

Closing in favor of PR 45302