HashSet isEmpty() method in java

by September 8, 2020 Java

Let’s learn HashSet isEmpty() method in java.

HashSet isEmpty() method in java

isEmpty() method of HashSet class returns true if this set contains no elements.

Syntax:

public boolean isEmpty()

Parameters:

isEmpty() method do not take any parameter.

Also read – HashSet in java

Now let’s see example on HashSet isEmpty() method.

import java.util.HashSet;
public class HashSetIsEmptyMethodExample
{
   public static void main(String[] args)
   {
      HashSet<String> hs = new HashSet<String>();
      hs.add("Welcome");
      hs.add("hello");
      hs.add("world");
      hs.add("core");
      hs.add("java");
      System.out.println("HashSet before using isEmpty() method: " + hs);
      // check if HashSet is empty
      System.out.println("Is the HashSet empty: " + hs.isEmpty());
      // clear HashSet using clear() method
      hs.clear();
      // again check if HashSet is empty
      System.out.println("Is the HashSet empty: " + hs.isEmpty());
   }
}

Output:

HashSet before using isEmpty() method: [core, world, java, Welcome, hello]
Is the HashSet empty: false
Is the HashSet empty: true