How do their APIs compare?

These two projects aren't really comparable at the "API" level in the same sense, because they serve completely different purposes. Let me lay out what each actually offers.

crossoverjie/jcsprout — not an API-providing project

JCSprout is a personal knowledge-base / learning repository, not a library or service with a public API. It's a collection of standalone Java demos and main-method-driven examples covering data structures, concurrency, JVM internals, etc. For instance:

• [src/main/java/com/crossoverjie/actual/Search.java:L39-L118] is a self-contained demo class with a main method that spins up threads to populate a ConcurrentHashMap and then exercises a static search(String keyWord) helper — it's a teaching example, not an exposed API.
• [src/main/java/com/crossoverjie/actual/LRUAbstractMap.java:L1-L26] documents (in comments) the intended behavior of a custom LRU map implementation (size limits, eviction callbacks like lruCallback and timeoutCallback), again as an educational implementation rather than a consumable API.
• [src/main/java/com/crossoverjie/proxy/jdk/CustomizeHandle.java:L16-L51] demonstrates JDK dynamic proxies via InvocationHandler.

So "API" here just means internal Java method signatures used for demonstration — there's no REST/HTTP surface, versioning, or public contract.

springfox/springfox — an actual framework with a real API surface

Springfox is a library/framework for generating OpenAPI/Swagger documentation from Spring applications, and it does expose real APIs at multiple levels:

1. Annotation-driven API for developers: consumers annotate Spring MVC/WebFlux controllers with things like @ApiOperation, @ApiParam, @ApiResponses, @Authorization, as shown in both the servlet and reactive Pet Store examples — [springfox-petstore/src/main/java/springfox/petstore/controller/PetController.java:L129-L168] and [springfox-petstore-webflux/src/main/java/springfox/petstore/webflux/controller/PetController.java:L131-L170]. These two controllers are nearly identical, showing how Springfox's annotation API is meant to work consistently across blocking (ResponseEntity) and reactive (Mono<ResponseEntity<...>>) styles.
2. HTTP endpoints it generates/serves: the Swagger UI JS client consumes REST endpoints like /swagger-resources/configuration/ui, /swagger-resources/configuration/security, and /swagger-resources, fetched asynchronously in [springfox-swagger-ui/src/web/js/springfox.js:L5-L54].
3. Integration entry points: per the README, applications wire in Springfox via @EnableOpenApi or the older @EnableSwagger2 family of annotations, and the springfox-boot-starter artifact [README.md:L35-L99].

Summary of the comparison

• jcsprout has no product-facing API at all — it's example code meant to be read, not integrated against.
• springfox has a layered API: annotations for describing your own REST API, generated JSON config/resource endpoints consumed by the UI, and enabling annotations for bootstrapping the library into a Spring app.

Given RepoPilot's verdict that jcsprout is stale (last commit 2 years ago), any comparison should also note that jcsprout isn't maintained as a dependency-grade library the way springfox is, so "comparing APIs" is really comparing a teaching repo's demo methods against a real framework's public contract.

FOLLOW_UPS:

• How does springfox handle reactive WebFlux controllers?
• What does jcsprout's LRU map eviction callback do?
• Is springfox still actively maintained or also stale?