Get the number of items in the stack.
Identify itself in Object.toString()
Determine if the stack is empty.
Get an iterator for the stack.
Iterating the stack will drain it.
Get an iterator for the stack that returns a [position, item] tuple.
Iterating the Stack will drain it.
Remove all items from the stack.
Get the next item and remove it from the stack.
Get the next item and leave it in the stack
Last in first out