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 , "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()); } } |
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 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()); } } |
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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