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Check if a HashMap is empty in Java
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
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
Updated on: 30-Jul-2019
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