Explanation of generic > in collection.sort/ comparable code?

Question

I use comparable interface all the time to provided natural ordering for my class through collection.sort.

Basically if I have a person class, I will get it to imple

Answer 1

You always use extends with generics wildcards, even if the type parameter implements an interface.

If you look at a class that implements Comparable, you'll see that it actually (should) implement Comparable, where T is the class itself.

It makes sense if you think about the type paramter passed to the Comparable interface and how it's used in the compareTo() method.

As PM 77-1 has eloquently pointed out, the super keyword allows for either the class, T, or one of its parents to implement Comparable.