Spring: @Async on a void method throws its exception into the void

A void @Async method has nowhere to report failure, so the exception reaches an AsyncUncaughtExceptionHandler you probably have not configured - and the default one only logs. Returning CompletableFuture makes the failure the caller's.

• Spring: @Cacheable does not cache what you think when the key collides
• Spring: RestTemplate and WebClient ship with no timeout at all
• Spring: @Order does not control bean creation order
• Spring: application events are synchronous and join the caller's transaction
• Spring: @ConfigurationProperties binds relaxed, @Value does not
• Spring: an exception in a Filter never reaches @RestControllerAdvice

---

Run this yourself in the Online Java Compiler, spin up a live REST API in the API Sandbox, or practise with Java interview questions.

Published 2026-08-25

© Java Coding Hub · About · Contact · Privacy · Terms