Write a Java program to how to use remove() method in HashMap

This program demonstrates how to use the remove method of the HashMap class to remove a key-value pair from a HashMap.

First, a HashMap object is created and some key-value pairs are added to it using the put method. Then, a for loop is used to iterate through the key-value pairs in the HashMap and print them to the console.

Next, the remove method is used to remove a key-value pair from the HashMap. The key 1002 is used as an argument to remove the key-value pair associated with it.

Finally, another for loop is used to iterate through the key-value pairs in the HashMap after the removal operation and print them to the console. This demonstrates that the key-value pair associated with the key 1002 has been successfully removed from the HashMap.

Source Code

import java.util.*;
public class Remove_Method
{
	public static void main(String args[])
	{
		HashMap<Integer,String> h =new HashMap<>();
		h.put(1000,"Sam");
		h.put(1001,"Sathish");
		h.put(1002,"Kumar");
		h.put(1003,"Ram"); 
		h.put(1004,"Pooja");
		for(Map.Entry e : h.entrySet())
		{
			System.out.println("Key : "+ e.getKey()+" || Value : "+e.getValue());
		}
 
		h.remove(1002);//Remove the key-value pair 
 
		System.out.println("\nAfter Remove the key-value pair elements in HashMap .. \n");
		for(Map.Entry e : h.entrySet())
		{
			System.out.println("Key : "+ e.getKey()+" || Value : "+e.getValue());
		}
	}
}

Output

Key : 1000 || Value : Sam
Key : 1001 || Value : Sathish
Key : 1002 || Value : Kumar
Key : 1003 || Value : Ram
Key : 1004 || Value : Pooja

After Remove the key-value pair elements in HashMap ..

Key : 1000 || Value : Sam
Key : 1001 || Value : Sathish
Key : 1003 || Value : Ram
Key : 1004 || Value : Pooja