Why use arrays when ArrayLists exist?

Hi Todd Baker

Good Question

Personally I will go with ArrayList because I can change the size at any time and also ArrayLists are really fast

However, to save memory Plain Arrays can be used when you have a fixed number of elements you’re sure this number is never going to change. ArrayLists usually allocate about twice the memory you need in advance so that you can append items very fast. So there is a wastage of memory if you are never going to add any more items.

Arrays also help to store data in multiple rows and columns also called multi-dimensional arrays

If you need a fixed number of elements or dealing with multiple dimensions, I suggest a plain array. If you need a simple list with lots of inserts and removals then Arraylist is the way to go.

But even with that, you can still simultaneously enjoy the strength of an Array and the strength of an ArrayList because Java allows you to convert from an Array to an ArrayList and vice-versa.

I hope this helps.. Merry coding!