HashSet toArray() method in Java with Example

The toArray() method of Java HashSet is used to form an array of the same elements as that of the HashSet. Basically, it copies all the element from a HashSet to a new array.

Syntax:

Object[] arr = HashSet.toArray()

Parameters: The method does not take any parameters.

Return Value: The method returns an array containing the elements similar to the HashSet.

Below programs illustrate the HashSet.toArray() method:

Program 1:

// Java code to illustrate toArray()

import java.util.*;

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

        // Use add() method to add
        // elements into the HashSet
        abs_col.add("Welcome");
        abs_col.add("To");
        abs_col.add("Geeks");
        abs_col.add("For");
        abs_col.add("Geeks");

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

        // Creating the array and using toArray()
        Object[] arr = abs_col.toArray();

        System.out.println("The array is:");
        for (int j = 0; j < arr.length; j++)
            System.out.println(arr[j]);
    }
}

Output:

The HashSet: [Geeks, For, Welcome, To]
The array is:
Geeks
For
Welcome
To

Program 2:

// Java code to illustrate toArray()

import java.util.*;

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

        // Use add() method to add
        // elements into the HashSet
        abs_col.add(10);
        abs_col.add(15);
        abs_col.add(30);
        abs_col.add(20);
        abs_col.add(5);
        abs_col.add(25);

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

        // Creating the array and using toArray()
        Object[] arr = abs_col.toArray();

        System.out.println("The array is:");
        for (int j = 0; j < arr.length; j++)
            System.out.println(arr[j]);
    }
}

Output:

The HashSet: [20, 5, 25, 10, 30, 15]
The array is:
20
5
25
10
30
15