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Java IdentityHashMap remove() Method with Example

IdentityHashMap Class remove() method: Here, we are going to learn about the remove() method of IdentityHashMap Class with its syntax and example.
Submitted by Preeti Jain, on March 06, 2020

IdentityHashMap Class remove() method

• remove() method is available in java.util package.
• remove() method is used to remove the key-value pair for the given key element (key_ele) when it exists in this IdentityHashMap.
• remove() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• remove() method does not throw an exception at the time of removing the key-value pair.

Syntax:

    public Value remove(Object key_ele);

Parameter(s):

• Object key_ele – represents the key element whose mapped value and key to be removed.

Return value:

The return type of the method is Value, it returns the removed value linked with the given key element (key_ele) when exists otherwise it returns null.

Example:

// Java program to demonstrate the example 
// of Value remove(Object key_ele) method
// of IdentityHashMap 

import java.util.*;

public class RemoveOfIdentityHashMap {
    public static void main(String[] args) {
        // Instantiates a IdentityHashMap object
        Map < Integer, String > map = new IdentityHashMap < Integer, String > ();

        // By using put() method is to add
        // key-value pairs in a IdentityHashMap
        map.put(10, "C");
        map.put(20, "C++");
        map.put(50, "JAVA");
        map.put(40, "PHP");
        map.put(30, "SFDC");

        // Display IdentityHashMap
        System.out.println("IdentityHashMap: " + map);

        // By using remove() method is to remove 
        // the mappings exists for the given key
        // element in this IdentityHashMap

        map.remove(50);

        // Display Modified IdentityHashMap
        System.out.print("map.remove(50): " + map);
    }
}

Output

IdentityHashMap: {20=C++, 40=PHP, 50=JAVA, 30=SFDC, 10=C}
map.remove(50): {20=C++, 40=PHP, 30=SFDC, 10=C}