What's the purpose: api.jar + impl.jar + bundle.jar?

Question

I see many Java packages have api, impl and bundle jars (name-api.jar, name-impl.jar, name-bundle.jar). Could someone explain what those mean? Are all three needed by the ap

Answer 1

api.jar contains API interfaces. These are interfaces as a contract that the implementation of the API should follow.

impl.jar is the implementation of the api.jar. You can't just have the impl.jar without the api.jar.

bundle.jar is the resources (if I'm not mistaken). Those are resources needed for the implementation code necessary to run.