Why we are using equals() method in HashMap and HashSet without implementing comparator interface? : <p>Why we are using equals() method in HashMap and HashSet without implementing the comparator interface?. I have seen some example programs in the above concept. But there without comparator interface, they are using equals() and hashcode() method. My question is ,can we use those methods without comparator interface? And also can we use equals() and hashcode() and compareTo() methods with comparable interface ?</p>
