How do their APIs compare?

At a high level, these two libraries solve very different problems, so their "APIs" aren't directly comparable feature-for-feature, but here's how they contrast based on what's in the retrieved data:

greenrobot/eventbus — a publish/subscribe event bus API

• Core interaction model: register() / unregister() a subscriber object, then post() events which get dispatched to annotated handler methods. This is described comparatively in [COMPARISON.md:L1-L40].
• Subscriber methods are declared via annotations, and since EventBus 3.0 these can be precompiled/indexed for performance instead of resolved via reflection at runtime — see the generated-index support in [EventBus/src/org/greenrobot/eventbus/meta/SubscriberInfoIndex.java:L1-L20], [EventBus/src/org/greenrobot/eventbus/meta/SubscriberInfo.java:L1-L20], and [EventBus/src/org/greenrobot/eventbus/meta/AbstractSubscriberInfo.java:L1-L24].
• SubscriberMethod [EventBus/src/org/greenrobot/eventbus/SubscriberMethod.java:L1-L20] is the internal representation used both by reflection-based lookup and by the generated indexes, tying together a method, its thread mode, and event type.
• Distinctive API-level features per [COMPARISON.md:L1-L40] and [COMPARISON.md:L36-L75]: event inheritance, subscriber inheritance, sticky events (caching most recent event for late subscribers), and explicit thread mode control — delivery can happen on the posting thread, main thread, or background thread, plus fully asynchronous delivery. This threading control is a key API differentiator versus alternatives like Otto, which (per the comparison table) lacks main-thread/background delivery modes and async delivery entirely.
• The API is intentionally small and centered on a handful of verbs (register/unregister/post) plus annotation metadata, rather than dozens of utility classes.

blankj/androidutilcode — from the README excerpt, this is structured as a large collection of independent static utility classes (the utilcode module for common needs, subutil for less-common helpers) rather than a single cohesive API surface like EventBus. The README doesn't describe a unifying interaction pattern; instead it points to per-module README docs (utilcode/subutil) for the actual utility APIs. I don't have specific utility class/method signatures in the retrieved chunks — if you want a concrete API comparison (e.g., how androidutilcode's utility methods are called versus EventBus's pub/sub calls), I can search for specific utility classes.

Summary of the contrast: EventBus exposes a narrow, opinionated messaging API (register/post/unregister plus annotation-driven handlers with thread-mode semantics), whereas androidutilcode exposes a broad surface of many small, independent static helper utilities across two modules with no shared pub/sub or lifecycle concept between them.

Want me to pull in specific utility classes from androidutilcode (e.g., a specific XxxUtils class) so we can compare method-level API design directly against EventBus's register/post calls?

FOLLOW_UPS:

• Show EventBus's register/post method signatures in detail?
• What utility classes exist in androidutilcode's utilcode module?
• How does EventBus implement sticky event caching?