IdentityHashMap get() Method in Java
Last Updated :
23 Jul, 2018
The java.util.IdentityHashMap.get() method of IdentityHashMap class is used to retrieve or fetch the value mapped by a particular key mentioned in the parameter. It returns NULL when the map contains no such mapping for the key.
Syntax:
IdentityHashMap.get(Object key_element)
Parameter: The method takes one parameter
key_element of object type and refers to the key whose associated value is supposed to be fetched.
Return Value: The method returns the value associated with the
key_element in the parameter.
Below programs illustrates the working of java.util.IdentityHashMap.get() method:
Program 1:
Java
// Java code to illustrate the get() method
import java.util.*;
public class Identity_Hash_Map_Demo {
public static void main(String[] args)
{
// Creating an empty IdentityHashMap
Map<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);
// Getting the value of 25
System.out.println("The Value is: " +
identity_hash.get(25));
// Getting the value of 10
System.out.println("The Value is: " +
identity_hash.get(10));
}
}
Output:
Initial Mappings are: {10=Geeks, 30=You, 20=Geeks, 25=Welcomes, 15=4}
The Value is: Welcomes
The Value is: Geeks
Program 2:
Java
// Java code to illustrate the get() method
import java.util.*;
public class Identity_Hash_Map_Demo {
public static void main(String[] args)
{
// Creating an empty IdentityHashMap
Map<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);
// Getting the value of "Geeks"
System.out.println("The Value is: " +
identity_hash.get("Geeks"));
// Getting the value of "You"
System.out.println("The Value is: " +
identity_hash.get("You"));
}
}
Output:
Initial Mappings are: {Geeks=20, Welcomes=25, You=30, 4=15}
The Value is: 20
The Value is: 30
Note: The same operation can be performed with any type of Mappings with variation and combination of different data types.
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