How HashSet Works Internally In Java?

As we know set will never contain duplicate elements.
But how in java Set interface implemented class HashSet achieve this uniqueness. In this post, we will discuss about this.

HashSet uses HashMap internally to store it’s objects. Every constructor of HashSet class internally creates one HashMap object.

/**
* Constructs a new, empty set; the backing HashMap instance has
* default initial capacity (16) and load factor (0.75).
*/
public HashSet() {
map = new HashMap<>();
}