HashMap clone() Method in Java Last Updated : 13 Dec, 2024 Comments Improve Suggest changes Like Article Like Report The clone() method of the HashMap class in Java is used to create a shallow copy of the specified HashMap. The method returns a new HashMap that contains the same key-value mappings as the original HashMap.Example 1: Here, we will use the clone() method to clone a HashMap of Integer keys and String values. Java // Mapping String values to Integer keys import java.util.HashMap; public class GFG { public static void main(String[] args) { // Create a HashMap and add // key-value pairs HashMap<Integer, String> hm = new HashMap<>(); hm.put(1, "Java"); hm.put(2, "C++"); hm.put(3, "Python"); // Print the original HashMap System.out.println("Original HashMap: " + hm); // Clone the HashMap HashMap<Integer, String> cl = (HashMap<Integer, String>) hm.clone(); // Print the cloned HashMap System.out.println("Cloned HashMap: " + cl); } } OutputOriginal HashMap: {1=Java, 2=C++, 3=Python} Cloned HashMap: {1=Java, 2=C++, 3=Python} Explanation: In the above example, the clone() method creates a shallow copy of the HashMap. Both "hm" and "cl" contain the same key-value pairs.To know more about Shallow copy and Deep copy refer this article: Shallow copy and Deep copy.Syntax of HashMap clone() Methodpublic Object clone()Parameters: The method does not take any parameters.Return Value: The clone() method returns a shallow copy of the HashMap.Points to Remember:The clone is shallow means the keys and values themselves are not cloned, but references to them are copied.Changes to mutable objects inside the HashMap will reflect in both the original and the cloned HashMap.Example 2: Here, we will use the clone() method to clone a HashMap of String keys and Integer values. Java // Mapping Integer Values to String Keys import java.util.*; public class GFG { public static void main(String[] args) { // Creating an empty HashMap HashMap<String, Integer> hm = new HashMap<String, Integer>(); // Mapping string keys to integer values hm.put("Java", 1); hm.put("C++", 2); hm.put("Python", 3); // Print and display the HashMap System.out.println("Original HashMap: " + hm); // Clone the HashMap HashMap<String, Integer> cl = (HashMap<String, Integer>) hm.clone(); System.out.println("Cloned HashMap: " + cl); } } OutputOriginal HashMap: {Java=1, C++=2, Python=3} Cloned HashMap: {Java=1, C++=2, Python=3} Important Points: The same operation can be performed with any type of mappings with variation and combination of different data types.clone() method does the shallow copy. But here the values in the original and cloned hashmap will not affect each other because primitive data type is used. Comment More infoAdvertise with us Next Article HashMap compute() Method in Java chinmoy lenka Follow Improve Article Tags : Misc Java Java-Collections Java - util package Java-Functions Java-HashMap +2 More Practice Tags : JavaJava-CollectionsMisc Similar Reads HashMap in Java In Java, HashMap is part of the Java Collections Framework and is found in the java.util package. It provides the basic implementation of the Map interface in Java. HashMap stores data in (key, value) pairs. Each key is associated with a value, and you can access the value by using the corresponding 15+ min read HashMap clear() Method in Java The clear() method of the HashMap class in Java is used to remove all of the elements or mappings (key-value pairs) from a specified HashMap.Example 2: Here, we will use the clear() method to clear a HashMap of Integer keys and String values. 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