Stack
The Stack extends the Vector with stack functionality.
boolean empty() : Tests if this stack is empty.
Object peek() : Looks at the object at the top of this
stack without removing it.
Object pop() : Removes the object at the top of this
stack and returns that object as the
void push(Object): Pushes an item onto the top of this stack.
int search(Object): Returns where an object is on this stack.