Another Stack implementation in Java
It looks like it is doing what it should be doing. 


I don't understand that remark. In particular, you posted no unit tests or other evidence of the target code being exercised in usual cases and in edge cases.

    private T t;


What is that? The ctor doesn't affect it. It doesn't appear to contribute to any Stack invariants. Why can't pop() and peek() simply return null?

    if (stack.size() != 0) {
        return false;
    } return true;


Don't show that at an interview. Use the more natural return stack.size() == 0 instead.

For some workloads involving a large stack, this implementation will show worse performance than one that uses a doubly linked list.