Java “Type parameter X is not within its bound; should implement Comparable” (LocalDateTime as key in map)

Question

I have implemented my own Map called AVLTreeMap. Here is the class signature.

public class AVLTreeMap, V>

Answer 1

Your generic signature for a Comparable is a little off, this

public class AVLTreeMap<K extends Comparable<K>, V>

Should be something like

public class AVLTreeMap<K extends Comparable<? super K>, V>