Arraylist of subclasses in java

Question

Say I have one superclass, and several subclasses inheriting it. I'd like to cram all of them into the same Arraylist for easy interaction, because for this one specific interaction, im only messing with stuff they have in common from the superclass.

Is this doable, or will I absolutely need a separate Arraylist for each object type?

If it is, how?

If ArrayLists can't do this, are there any other operable collections that could?

Answer 1

you can create the arraylist as

List<YourSuperClass> list = new ArrayList<YourSuperClass>();

Answer 2

I think what you're after is: ArrayList<? extends SuperClass>.

• MeBigFatGuy: unfortunately you can't insert elements into a list defined this way.. This is a read-only definition.
• Johnny Tarr: BigFatGuy was right. Although, knowing that I can do this with arraylists will probably still be useful.