IdentityHashMap clone() Method in Java

IdentityHashMap containsKey() Method in Java

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 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, "Beginner"); 
        identity_hash.put(15, "4"); 
        identity_hash.put(20, "Beginner"); 
        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=Beginner, 30=You, 20=Beginner, 25=Welcomes, 15=4}
The cloned map: {10=Beginner, 30=You, 20=Beginner, 25=Welcomes, 15=4}

Program 2:

// 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("Beginner", 10); 
        identity_hash.put("4", 15); 
        identity_hash.put("Beginner", 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: {Beginner=20, Welcomes=25, You=30, 4=15}
The cloned map: {Beginner=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.

Tags:

#Java-Collections #Java-Functions #java-IdentityHashMap #Java #Java #Java-Collections

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IdentityHashMap clone() Method in Java

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