IdentityHashMap clone() Method in Java Last Updated : 23 Jul, 2018 Comments Improve Suggest changes Like Article Like Report The java.util.IdentityHashMap.clone() method is used to return a shallow copy of the mentioned hash map. It just creates a copy of the map. Syntax: Identity_HashMap.clone() Parameters: The method does not take any parameters. Return Value: The method just returns a copy of the hash map. Below programs are used to illustrate the working of java.util.IdentityHashMap.clone() Method: Program 1: Java // Java code to illustrate the clone() method import java.util.*; public class Identity_Hash_Map_Demo { public static void main(String[] args) { // Creating an empty IdentityHashMap IdentityHashMap<Integer, String> identity_hash = new IdentityHashMap<Integer, String>(); // Mapping string values to int keys identity_hash.put(10, "Geeks"); identity_hash.put(15, "4"); identity_hash.put(20, "Geeks"); identity_hash.put(25, "Welcomes"); identity_hash.put(30, "You"); // Displaying the IdentityHashMap System.out.println("Initial Mappings are: " + identity_hash); // Displaying the cloned Map using clone() System.out.println("The cloned map: " + identity_hash.clone()); } } Output: Initial Mappings are: {10=Geeks, 30=You, 20=Geeks, 25=Welcomes, 15=4} The cloned map: {10=Geeks, 30=You, 20=Geeks, 25=Welcomes, 15=4} Program 2: Java // Java code to illustrate the clone() method import java.util.*; public class Identity_Hash_Map_Demo { public static void main(String[] args) { // Creating an empty hash map IdentityHashMap<String, Integer> identity_hash = new IdentityHashMap<String, Integer>(); // Mapping int values to string keys identity_hash.put("Geeks", 10); identity_hash.put("4", 15); identity_hash.put("Geeks", 20); identity_hash.put("Welcomes", 25); identity_hash.put("You", 30); // Displaying the IdentityHashMap System.out.println("Initial Mappings are: " + identity_hash); // Displaying the cloned map using clone() System.out.println("The cloned map: " + identity_hash.clone()); } } Output: Initial Mappings are: {Geeks=20, Welcomes=25, You=30, 4=15} The cloned map: {Geeks=20, Welcomes=25, You=30, 4=15} Note: The same operation can be performed with any type of Mappings with variation and combination of different data types. 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