Java HashSet clear() Method (original) (raw)

Last Updated : 22 Jan, 2025

The **clear() method of the HashSet class in Java is used to clear all the elements from the HahSet. This method makes the HashSet empty but **does not delete the HashSet itself. It simply removes all elements, leaving the set ready for reuse.

Syntax of HashSet clear() Method

void clear()

Key Points:

• After calling clear() the HashSet size becomes 0.
• The clear() does not affect the internal capacity of the HashSet.

**Example: This example demonstrates how the clear() method removes all the elements from the HashSet.

Java `

// Java program to demonstrates the working of clear() import java.util.*;

public class Geeks { public static void main(String[] args) { // Create a HashSet HashSet hs = new HashSet();

    // Add elements to HashSet
    hs.add(1);
    hs.add(2);
    hs.add(3);

    System.out.println("HashSet before clear(): " + hs);

    // Clear the HashSet
    hs.clear();

    System.out.println("HashSet After clear(): " + hs);
    System.out.println("HashSet isEmpty(): "
                       + hs.isEmpty());
}

}

`

Output

HashSet before clear(): [1, 2, 3] HashSet After clear(): [] HashSet isEmpty(): true