Find the size of a HashMap in Java

Java 8Object Oriented ProgrammingProgramming

Use the size() method to get the size of HashMap. Let us first create a HashMap

HashMap hm = new HashMap();

Now, add some elements −

hm.put("Bag", new Integer(1100));
hm.put("Sunglasses", new Integer(2000));
hm.put("Franes", new Integer(800));
hm.put("Wallet", new Integer(700));
hm.put("Belt", new Integer(600));

Since, we added 5 elements above, therefore, the size() method will give 5 as the result −

set.size()

The following is an example to find the size of HashMap −

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("Franes", new Integer(800));
      hm.put("Wallet", new Integer(700));
      hm.put("Belt", new Integer(600));
      Set set = hm.entrySet();
      System.out.println("Elements in HashMap...");
      // Get an iterator
      Iterator i = set.iterator();
      // Display elements
      while(i.hasNext()) {
         Map.Entry me = (Map.Entry)i.next();
         System.out.print(me.getKey() + ": ");
         System.out.println(me.getValue());
      }
      System.out.println();
      System.out.println("Size of HashMap = "+set.size());
   }
}

Output

Elements in HashMap...
Franes: 800
Belt: 600
Wallet: 700
Bag: 1100
Sunglasses: 2000
Size of HashMap = 5
raja
Published on 11-Jan-2019 12:14:56
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