[penrod]

One example would be that with Spark you could procedurally create and register multiple Route instances. That is not an option with an annotation-based API that requires you to have a distinct annotated class per route.

More abstractly, one of the characteristics of object-oriented design is the use of polymorphic objects. APIs which require you to define monomorphic annotated classes violate this and lose generality as a result. They are effectively class-oriented or method-oriented rather than true OO.

[meddlepal]

Why would you want that feature? Also I'm pretty sure nothing about jaxrs annotations prevents such a thing from being possible but the servlet container may get in your way of doing it easily.

[penrod]

Why would you want to procedurally generate routes or verbs? I dunno, perhaps there might be a use case where one would want to define them in configuration or a database. But being able to do something like this is not a "feature," it's just the inherent flexibility of expressing semantics in code.

Why would you want an API that breaks the flexibility of code by forcing it to be glorified XML?