java.lang.Object | +--java.util.Vector | +--java.util.Stack
The Stack
class represents a last-in-first-out
(LIFO) stack of objects. It extends class Vector with five
operations that allow a vector to be treated as a stack. The usual
push and pop operations are provided, as well as a
method to peek at the top item on the stack, a method to test
for whether the stack is empty, and a method to search
the stack for an item and discover how far it is from the top.
When a stack is first created, it contains no items.
Fields inherited from class java.util.Vector |
capacityIncrement,
elementCount,
elementData |
Constructor Summary | |
Stack()
Creates an empty Stack. |
Method Summary | |
boolean |
empty()
Tests if this stack is empty. |
Object |
peek()
Looks at the object at the top of this stack without removing it from the stack. |
Object |
pop()
Removes the object at the top of this stack and returns that object as the value of this function. |
Object |
push(Object item)
Pushes an item onto the top of this stack. |
int |
search(Object o)
Returns the 1-based position where an object is on this stack. |
Methods inherited from class java.util.Vector |
addElement,
capacity,
contains,
copyInto,
elementAt,
elements,
ensureCapacity,
firstElement,
indexOf,
indexOf,
insertElementAt,
isEmpty,
lastElement,
lastIndexOf,
lastIndexOf,
removeAllElements,
removeElement,
removeElementAt,
setElementAt,
setSize,
size,
toString,
trimToSize |
Methods inherited from class java.lang.Object |
equals,
getClass,
hashCode,
notify,
notifyAll,
wait,
wait,
wait |
Constructor Detail |
public Stack()
Method Detail |
public Object push(Object item)
addElement(item)
item
- the item to be pushed onto this stack.item
argument.Vector.addElement(java.lang.Object)
public Object pop()
public Object peek()
public boolean empty()
true
if and only if this stack contains
no items; false
otherwise.public int search(Object o)
o
- the desired object.-1
indicates that the object is not on the stack.