Java Hashmap clone() Method

import java.util.*;

public class Main
{
  public static void main (String[]args)
  {

    // Creating an empty HashMap
    HashMap < String, Integer > hash_map_1 =
      new HashMap < String, Integer > ();


    // Mapping integer values to string keys in a empty hashmap
    hash_map_1.put ("Maths", 80);
    hash_map_1.put ("English", 75);
    hash_map_1.put ("Hindi", 85);
    hash_map_1.put ("Science", 90);

    System.out.println ("Original hashmap : " + hash_map_1);


    //making a clone of the hashmap
    HashMap < String, Integer > clone_hashmap =
      (HashMap < String, Integer >) hash_map_1.clone ();

    System.out.println ("clone hashmap : " + clone_hashmap);


  }
}