023 [Collection] Which all classes implement Set interface?
1. SortedSet - It is an interface which extends Set. All elements inserted into the interface must implement Comparable or Comparator interface.
2. TreeSet - It is the implementation of SortedSet interface.This implementation provides guaranteed log(n) time cost for the basic operations (add, remove and contains). The class is not synchronized.
3. HashSet: This class implements the Set interface, backed by a hash table (actually a HashMap instance). It makes no guarantees as to the iteration order of the set; This class permits the null element. This class offers constant time performance for the basic operations (add, remove, contains and size), assuming the hash function disperses the elements properly among the buckets