Create ArrayList from array

Question

I have an array that is initialized like:

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

I would like to convert this array into an object of the ArrayList class.

ArrayList<Element> arraylist = ???; 

Answer 1

new ArrayList<>(Arrays.asList(array)); 

Answer 2

Given:

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

The simplest answer is to do:

List<Element> list = Arrays.asList(array); 

This will work fine. But some caveats:

1. The list returned from asList has fixed size. So, if you want to be able to add or remove elements from the returned list in your code, you'll need to wrap it in a new ArrayList. Otherwise you'll get an UnsupportedOperationException.
2. The list returned from asList() is backed by the original array. If you modify the original array, the list will be modified as well. This may be surprising.