Check if a HashMap is empty in Java

Java 8Object Oriented ProgrammingProgramming

Use the isEmpty() method to check of a HashMap is empty or not. Let us first create the HashMap −

HashMap hm = new HashMap();

Now, add some elements −

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

Since, we added elements above, therefore, the HashMap isn’t empty. Let us check −

set.isEmpty()

The following is an example to check if a HashMap is empty or not −

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("Wallet", new Integer(700));
      hm.put("Belt", new Integer(600));
      // Get a set of the entries
      Set set = hm.entrySet();
      // 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("Is the HashMap with empty elements? "+set.isEmpty());
   }
}

Output

Belt: 600
Wallet: 700
Bag: 1100
Is the HashMap with empty elements? False
raja
Published on 11-Jan-2019 12:09:12
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