Set toArray() method in Java with Example

Last Updated : 31 Dec, 2018

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

Syntax:

Object[] toArray()

Parameters: The method does not take any parameters.

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

Below programs illustrate the Set.toArray() method:

Program 1:

// Java code to illustrate toArray() 
  
import java.util.*; 
  
public class SetDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty Set 
        Set<String> abs_col = new HashSet<String>(); 
  
        // Use add() method to add 
        // elements into the Set 
        abs_col.add("Welcome"); 
        abs_col.add("To"); 
        abs_col.add("Geeks"); 
        abs_col.add("For"); 
        abs_col.add("Geeks"); 
  
        // Displaying the Set 
        System.out.println("The Set: "
                           + 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 Set: [Geeks, For, Welcome, To]
The array is:
Geeks
For
Welcome
To

Program 2:

// Java code to illustrate toArray() 
  
import java.util.*; 
  
public class SetDemo { 
    public static void main(String args[]) 
    { 
        // Creating an empty Set 
        Set<Integer> abs_col = new HashSet<Integer>(); 
  
        // Use add() method to add 
        // elements into the Set 
        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 Set 
        System.out.println("The Set: " + 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 Set: [20, 5, 25, 10, 30, 15]
The array is:
20
5
25
10
30
15

Reference: https://docs.oracle.com/javase/7/docs/api/java/util/Set.html#toArray()

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