Please make it clear which samples use OpenAPI 2 vs. 3

[davewichers]

Given the transition, and the fact that some methods went away in this update, can you update the code examples to clearly indicate whether the annotations used in the examples work with swagger-api 1.x vs 2.x (OpenAPI 2 vs 3)? It's very frustrating to look for an example, find one that is close, try it out, and find out it won't even compile because of this. Ideally, you'd have examples for both for each example, or upgrade all existing examples to use the new version (or something).

For example: https://github.com/swagger-api/swagger-samples/blob/master/java/java-servlet/src/main/java/io/swagger/sample/servlet/SampleServlet.java - this uses the older swagger library not the new one that supports OpenAPI 3.