This question relates both to C# and Java

If you have a collection which is not modified and that collection reference is shared between two threads what happens when you iterate on each thread??

ThreadA: Collection.iterator ThreadA: Collection.moveNext ThreadB: Collection.iterator ThreadB: Collection.moveNext

Will threadB see the first element?

Is the iterator always reset when it is requested? What happens if this is interleaved so movenext and item is interleaved? Is there a danger that you dont process all elements??