Java 8 introduced the ability for interfaces to have default methods. Default methods are methods with an implementation. This is in stark contrast to the notion that interfaces should only have unimplemented, abstract methods.
Whenever I find a link to my site on another website, I wonder if that link is a dofollow or nofollow link. One way, of course, is to view the source of the page and see if that link has a nofollow attribute.