What's the correct way to run code right after a bean's dependencies are injected?

Implement `InitializingBean.afterPropertiesSet()`, or more commonly, annotate a method with `@PostConstruct` — Spring guarantees this runs after all `@Autowired`/constructor dependencies are set, but before the bean is handed out to other beans. This is the right place for validation or warm-up logic that needs the bean's dependencies to already be present.