Creating a new ArrayList in Java

Question

Assuming that I have a class named Class,

And I would like to make a new ArrayList that it\'s values will be of type Class.

My question

Answer 1

If you just want a list:

ArrayList myList = new ArrayList();

If you want an arraylist of a certain length (in this case size 10):

List myList = new ArrayList(10);

If you want to program against the interfaces (better for abstractions reasons):

List myList = new ArrayList();

Programming against interfaces is considered better because it's more abstract. You can change your Arraylist with a different list implementation (like a LinkedList) and the rest of your application doesn't need any changes.