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Java program to remove all elements of HashSet collection

Java example to remove all elements of HashSet collection.
Submitted by Nidhi, on May 08, 2022

Problem Solution:

In this program, we will create a set using the HashSet collection to store integer elements. Then we will remove all elements of HashSet using the clear() method.

Program/Source Code:

The source code to remove all elements of the HashSet collection is given below. The given program is compiled and executed successfully.

// Java program to remove all elements of 
// HashSet collection

import java.util.*;

public class Main {
  public static void main(String[] args) {

    HashSet < Integer > nums = new HashSet();

    nums.add(1);
    nums.add(2);
    nums.add(3);
    nums.add(4);

    System.out.println("Set items: ");
    Iterator < Integer > itr = nums.iterator();
    while (itr.hasNext()) {
      System.out.println(" " + itr.next());
    }

    nums.clear();

    System.out.println("Set items: ");
    Iterator < Integer > itr1 = nums.iterator();
    while (itr1.hasNext()) {
      System.out.println(" " + itr1.next());
    }
  }
}

Output:

Set items: 
 1
 2
 3
 4
Set items:

Explanation:

In the above program, we imported the "java.util.*" package to use the HashSet collection. Here, we created a public class Main that contains a main() method.

The main() method is the entry point for the program. And, we created a set nums to store integer data elements using HashSet collection. Then we removed all elements from the nums HashSet. After that, we printed the updated collection.

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