org.ceryle.util
Class Queue

java.lang.Object
  java.util.AbstractCollection<E>
      java.util.AbstractList<E>
          java.util.Vector<E>
              java.util.Stack
                  org.ceryle.util.Queue

All Implemented Interfaces:

Serializable, Cloneable, Iterable, Collection, List, RandomAccess

public class Queue
extends Stack

Queue extends java.util.Stack (a class that represents a last-in-first-out (LIFO) stack of objects) to allow to rotate its contents up (top element --> bottom) or down (bottom element --> top).

As a queue, it also adds enqueue (a synonym for 'add') and dequeue(), which extracts items from the bottom of the Stack rather than the top, in first-in-first-out (FIFO) fashion.

Since:

JDK1.2

Version:

$Id: Queue.java,v 3.3 2007-06-15 12:09:57 altheim Exp $

Author:

Murray Altheim

See Also:

Stack, Serialized Form

Field Summary

Fields inherited from class java.util.Vector

capacityIncrement, elementCount, elementData

Fields inherited from class java.util.AbstractList

modCount

Constructor Summary

Queue()

Method Summary

Object	dequeue() Treats the Stack (backed up by a Vector) as a first-in-first-out (FIFO) queue, dequeue retrieving the bottom (zero-eth) element.
boolean	enqueue(Object o) Treats the Stack (backed up by a Vector) as a first-in-first-out (FIFO) queue, enqueue a synonym for java.util.Vector's add or java.util.Stack's push, all of which add the new Object o to the top of the underlying Vector.
void	rotateDown() Rotates the Stack by removing the first element and pushing it to the end of the Stack.
void	rotateDown(int count) Rotates the Stack count times by repeatedly removing the first element and pushing it to the end of the Stack.
void	rotateUp() Rotates the Stack by popping the last element and inserting it at the beginning of the Stack.
void	rotateUp(int count) Rotates the Stack count times by repeatedly popping the last element and inserting it at the beginning of the Stack.

Methods inherited from class java.util.Stack

empty, peek, pop, push, search

Methods inherited from class java.util.Vector

add, add, addAll, addAll, addElement, capacity, clear, clone, contains, containsAll, copyInto, elementAt, elements, ensureCapacity, equals, firstElement, get, hashCode, indexOf, indexOf, insertElementAt, isEmpty, lastElement, lastIndexOf, lastIndexOf, remove, remove, removeAll, removeAllElements, removeElement, removeElementAt, removeRange, retainAll, set, setElementAt, setSize, size, subList, toArray, toArray, toString, trimToSize

Methods inherited from class java.util.AbstractList

iterator, listIterator, listIterator

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.List

iterator, listIterator, listIterator

Constructor Detail

Queue

public Queue()

Method Detail

rotateUp

public void rotateUp(int count)
              throws EmptyStackException

Rotates the Stack count times by repeatedly popping the last element and inserting it at the beginning of the Stack.

Throws:

EmptyStackException

rotateUp

public void rotateUp()
              throws EmptyStackException

Rotates the Stack by popping the last element and inserting it at the beginning of the Stack.

Throws:

EmptyStackException

rotateDown

public void rotateDown(int count)
                throws EmptyStackException

Rotates the Stack count times by repeatedly removing the first element and pushing it to the end of the Stack.

Throws:

EmptyStackException

rotateDown

public void rotateDown()
                throws EmptyStackException

Rotates the Stack by removing the first element and pushing it to the end of the Stack.

Throws:

EmptyStackException

enqueue

public boolean enqueue(Object o)

Treats the Stack (backed up by a Vector) as a first-in-first-out (FIFO) queue, enqueue a synonym for java.util.Vector's add or java.util.Stack's push, all of which add the new Object o to the top of the underlying Vector.

Returns:

true if the object was added

dequeue

public Object dequeue()
               throws EmptyStackException

Treats the Stack (backed up by a Vector) as a first-in-first-out (FIFO) queue, dequeue retrieving the bottom (zero-eth) element.

Throws:

EmptyStackException