Returns: the object at the top of this stack (the last item of the Vector object). 一样是object 啊
peek public E peek() Looks at the object at the top of this stack without removing it from the stack. Returns: the object at the top of this stack (the last item of the Vector object). Throws: EmptyStackException - if this stack is empty.
the object at the top of this stack (the last item of the Vector object). 一样是object 啊
public E peek()
Looks at the object at the top of this stack without removing it from the stack. Returns:
the object at the top of this stack (the last item of the Vector object).
Throws:
EmptyStackException - if this stack is empty.