Description
Program to check if a HashMap is empty or not. We are using isEmpty() method of HashMap class to perform this check.
Program
import java.util.HashMap;
class HashMapIsEmptyExample{
public static void main(String args[]) {
// Create a HashMap
HashMap<Integer, String> hmap = new HashMap<Integer, String>();
// Checking whether HashMap is empty or not
/* isEmpty() method signature and description -
* public boolean isEmpty(): Returns true if this map
* contains no key-value mappings.
*/
System.out.println("Is HashMap Empty? "+hmap.isEmpty());
// Adding few elements
hmap.put(11, "Jack");
hmap.put(22, "Rock");
hmap.put(33, "Rick");
hmap.put(44, "Smith");
hmap.put(55, "Will");
// Checking again
System.out.println("Is HashMap Empty? "+hmap.isEmpty());
}
}
Output:
Is HashMap Empty? true Is HashMap Empty? false
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