Spring core. Default @Bean destroy method

As documented in Bean.destroyMethod:

As a convenience to the user, the container will attempt to infer a
destroy method against an object returned from the @Bean method. For
example, given an @Bean method returning an Apache Commons DBCP
BasicDataSource, the container will notice the close() method
available on that object and automatically register it as the
destroyMethod. This ‘destroy method inference’ is currently limited
to detecting only public, no-arg methods named ‘close’ or ‘shutdown’.

In other words, if you don’t specify destroyMethod, but the bean has a public close() or shutdown() method, it will be automatically used as the destroy-method.

To disable this inference, use @Bean(destroyMethod = "").