How to convert an Array to HashSet in Java? Example Tutorial

Converting an Array to HashSet in Java can be achieved by utilizing the HashSet constructor that takes a Collection as a parameter. 

Here's a step-by-step example tutorial on how to convert an Array to HashSet in Java: 

Step 1: Import the required classes.

import java.util.Arrays;
import java.util.HashSet;

Step 2: Declare and initialize an array with elements.

String[] array = {"apple", "banana", "orange", "kiwi", "banana"};

Step 3: Create a HashSet object and pass the array as a parameter to its constructor.

HashSet set = new HashSet<>(Arrays.asList(array));

Step 4: Now, the array elements have been converted to a HashSet. 

You can perform various operations on the set, such as adding or removing elements, checking for containment, or iterating through the elements. Here's a complete example demonstrating the conversion of an array to a HashSet and performing some operations:

import java.util.Arrays;
import java.util.HashSet;

public class ArrayToHashSetExample {
    public static void main(String[] args) {
        String[] array = {"apple", "banana", "orange", "kiwi", "banana"};

        HashSet set = new HashSet<>(Arrays.asList(array));

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

        // Add a new element to the HashSet
        set.add("grape");
        System.out.println("HashSet after adding 'grape': " + set);

        // Remove an element from the HashSet
        set.remove("banana");
        System.out.println("HashSet after removing 'banana': " + set);

        // Check if an element exists in the HashSet
        boolean containsKiwi = set.contains("kiwi");
        System.out.println("Does the HashSet contain 'kiwi'? " + containsKiwi);

        // Iterate through the HashSet
        System.out.println("Iterating through the HashSet:");
        for (String element : set) {
            System.out.println(element);
        }
    }
}

OUTPUT :

HashSet: [orange, kiwi, apple, banana]
HashSet after adding 'grape': [orange, kiwi, apple, grape, banana]
HashSet after removing 'banana': [orange, kiwi, apple, grape]
Does the HashSet contain 'kiwi'? true
Iterating through the HashSet:
orange
kiwi
apple
grape

In this example, the array is converted to a HashSet using the HashSet constructor that takes a Collection as a parameter. The resulting HashSet can be used to perform various operations efficiently, such as adding or removing elements, checking for containment, or iterating through the elements.