Check out example codes for "convert hashset to int array java". It will help you in understanding the concepts better.

Code Example 1

import java.util.Arrays;
import java.util.Set;
import java.util.HashSet;
class Main
{
    // Program to convert set of integer to array of int in Java
    public static void main(String args[])
    {
        Set<Integer> ints = new HashSet<>(Arrays.asList(1, 2, 3, 4, 5));
        int[] primitive = ints.stream()
                            .mapToInt(Integer::intValue)
                            .toArray();
        System.out.println(Arrays.toString(primitive));
    }
}

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