Improve error message for actorOf on typed ActorSystem#2798
Merged
He-Pin merged 1 commit intoapache:mainfrom Mar 28, 2026
Merged
Improve error message for actorOf on typed ActorSystem#2798He-Pin merged 1 commit intoapache:mainfrom
He-Pin merged 1 commit intoapache:mainfrom
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When calling system.actorOf() on a typed ActorSystem, provide a more helpful error message explaining that top-level actors should be spawned as children of the guardian behavior, or a classic ActorSystem should be used instead. The generic 'custom user guardian' message is preserved for non-typed custom guardians. Fix upstream bug: the isTypedGuardian check used startsWith with a package prefix that never matched due to case mismatch (T vs t). Use exact class name match instead. Upstream: akka/akka-core@f73fae3783 Cherry-picked from akka/akka-core v2.8.0, which is now Apache licensed. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Motivation
When users accidentally call classic actorOf on a typed ActorSystem, the error message was confusing and did not clearly explain the problem.
Modification
Improved the error message to clearly state that classic actor creation is not supported on typed ActorSystem, and suggest using typed actor spawning instead. Fixed isTypedGuardian detection.
Result
Users get actionable guidance when they hit this common migration pitfall.
References