HashSet clear() Method in Java

The Java.util.HashSet.clear() method is used to remove all the elements from a HashSet. Using the clear() method only clears all the element from the set and not deletes the set. In other words, we can say that the clear() method is used to only empty an existing HashSet.

Syntax:

Hash_Set.clear()

Parameters: The method does not take any parameter

Return Value: The function does not returns any value.

Below program illustrate the Java.util.HashSet.clear() method:

// Java code to illustrate clear()
import java.io.*;
import java.util.HashSet;

public class HashSetDemo{
    public static void main(String args[])
    {
        // Creating an empty HashSet
        HashSet<String> set = new HashSet<String>();

        // Use add() method to add elements into the Set
        set.add("Welcome");
        set.add("To");
        set.add("Geeks");
        set.add("4");
        set.add("Geeks");

        // Displaying the HashSet
        System.out.println("HashSet: " + set);

        // Clearing the HashSet using clear() method
        set.clear();

        // Displaying the final Set after clearing;
        System.out.println("The final set: " + set);
    }
}

Output:

HashSet: [4, Geeks, Welcome, To]
The final set: []