Question

I was wondering if it is possible to convert an Object into something else.

I have a Object which contains a series of numbers in a random order such as: 3, 4, 2, 5, 1 and wondering if I am able to turn it into an int[] or select certain elements from it, as in a number from the sequence?

EDIT:
so some of the code i have is:

//This contains all the different combinations of the numbers
ArrayList routePop4 = new ArrayList();
//This picks out the first one, just as a test
Object test = routePop4.get(0);

But the idea is that I want to loop through each element of test.

Answer 1

An Object cannot “contain a series of numbers”. However many subclasses of Object, such as all of the Collections can “contain a series of numbers”, and they come with a toArray() method to turn the contents of the collection into an array.

If you have a collection, but only have access to it as an Object, you need to cast it before you can work with it properly:

ArrayList<Integer> list = (ArrayList<Integer>)test;
Integer[] arr = list.toArray(new Integer[]{});

It’s fairly rare in day-to-day Java to actually be working with variables cast as Object, if you are, it should be a red flag that you may be doing something wrong. You can use generics to allow objects that contain other objects to do so generically, like so:

ArrayList<Integer> list = new ArrayList<Integer>();
list.add(1); // Can only add integers, list.add("a string") would fail at compile time
int n = list.get(0); // no need to cast, we know list only contains Integers

If you aren’t using a Collection, you’ll presumably need to roll your own, as Luke Taylor’s answer suggests. That said, you’ll get better answers if you can provide more information, the current text of your question doesn’t make sense in a Java context.