Create ArrayList from array

📝 Converting an Array into an ArrayList in Java

So you have an array of type Element[] and you want to convert it into an ArrayList<Element>. No worries, mate! I got your back! 💪

The Problem

Let's take a look at the example array we have:

Element[] array = {new Element(1), new Element(2), new Element(3)};

And here's what we want to achieve:

ArrayList<Element> arrayList = ???;

Basically, we want to populate the ArrayList with the elements from our existing array. But how do we do that? 🤔

The Solution

Fear not, my friend! Java has got a handy-dandy Arrays class with a method called asList() that can help us out here. Let's use it:

ArrayList<Element> arrayList = new ArrayList<>(Arrays.asList(array));

Voilà! 😎 By passing the array into Arrays.asList(), we create a List<Element> object, and then by passing that into the ArrayList constructor, we convert it into an ArrayList<Element>.

A Closer Look

Now, let's break down the solution and understand it better.

1. We start by calling Arrays.asList(array). This method takes an array as a parameter and returns a fixed-size list that wraps the original array. However, keep in mind that this list is not a regular ArrayList yet; it just implements the List interface.

2. By passing the list returned by Arrays.asList() into the ArrayList constructor, we create a proper ArrayList object that we can manipulate as we wish.

The Complication

Wait! Just a small caveat I have to mention: when using this method, the resulting ArrayList is still backed by the original array. That means any changes made to the ArrayList will also affect the original array and vice versa. So, if you modify any element in the ArrayList, the corresponding element in the original array will also be updated. Keep this in mind when dealing with mutable objects! 👀

The Call to Action

I hope this mini-guide has helped you understand how to convert an array into an ArrayList with ease. Now, it's time for you to put it to practice! ✨

Why not try converting an array of your own and explore the possibilities that come with using an ArrayList? Share your experience in the comments below, and let's keep the conversation going! 💬🚀