Modify the value associated with a given key in Java HashMap

First, create a HashMap and add elements to it −

// Create a hash map
HashMap hm = new HashMap();
// Put elements to the map
hm.put("Bag", new Integer(1100));
hm.put("Sunglasses", new Integer(2000));
hm.put("Frames", new Integer(800));
hm.put("Wallet", new Integer(700));
hm.put("Belt", new Integer(600));

Now, to modify the value associated with a given key, use the put() method. Here, we are modifying the value for the key “Frames” −

hm.put("Frames", "900");

The following is an example to modify the value associated with a given key −

Example

 Live Demo

import java.util.*;
public class Demo {
   public static void main(String args[]) {
      // Create a hash map
      HashMap hm = new HashMap();
      // Put elements to the map
      hm.put("Bag", new Integer(1100));
      hm.put("Sunglasses", new Integer(2000));
      hm.put("Frames", new Integer(800));
      hm.put("Wallet", new Integer(700));
      hm.put("Belt", new Integer(600));
      // Get a set of the entries
      Set set = hm.entrySet();
      System.out.println("Elements in HashMap...");
      System.out.println(set);
      hm.put("Frames", "900");
      System.out.println("\nUpdated HashMap Elements...");
      System.out.println(hm);
   }
}

Output

Elements in HashMap...
[Frames=800, Belt=600, Wallet=700, Bag=1100, Sunglasses=2000]

Updated HashMap Elements...
{Frames=900, Belt=600, Wallet=700, Bag=1100, Sunglasses=2000}