What is the <K, V> thing in a hashmap, and how do I use it in my own class? [duplicate]

Question

I have been trying to simply get a name for what the <> part of the declaration is called, to no luck. Can anyone tell me what it's called, how I can use it in my own class? For instance I may want to try and make my own kind of collection, and use new MyThing<String> for instance. Any help is appreciated, thanks!

Answer 1

That's the generic type declaration of the class. For example, to specify that a map is going to use strings as keys and integers as values:

Map<String, Integer> mymap = new HashMap<String, Integer>();