org.jboss.util.collection
Class ListQueue<E>

java.lang.Object
  java.util.AbstractCollection<E>
      org.jboss.util.collection.AbstractQueue<E>
          org.jboss.util.collection.ListQueue<E>

Type Parameters:

E - the element type

All Implemented Interfaces:

Iterable<E>, Collection<E>, Queue<E>

public class ListQueue<E>
extends AbstractQueue<E>

A ListQueue implements a first-in, first-out container using a List as a data structure.

Version:

$Revision: 2787 $

Author:

Jason Dillon

Field Summary

protected List<E>

list List container

Fields inherited from class org.jboss.util.collection.AbstractQueue

DEFAULT_MAXIMUM_SIZE, maximumSize

Fields inherited from interface org.jboss.util.collection.Queue

UNLIMITED_MAXIMUM_SIZE

Constructor Summary

ListQueue()
Construct a new unconstrained ListQueue using a LinkedList for a data-structure.

ListQueue(int maxSize)
Construct a new constrained ListQueue using a LinkedList for a data-structure.

ListQueue(List<E> list)
Construct a new unconstrained ListQueue.

ListQueue(List<E> list, int maxSize)
Construct a new constrained ListQueue.

Method Summary

protected boolean	addLast(E obj) Appends the given element to the end of this list.
E	getBack() Get the object at the back of the queue.
E	getFront() Get the object at the front of the queue.
Iterator<E>	iterator() Returns an iterator over the elements in this list in proper sequence.
protected E	removeFirst() Remove the first object in the queue.
Iterator<E>	reverseIterator() Returns an iterator over the elements in this list in reverse sequence.
int	size() Get the size of the queue.
String	toString() Return a String representation of this queue.

Methods inherited from class org.jboss.util.collection.AbstractQueue

add, clear, getMaximumSize, isEmpty, isFull, remove, setMaximumSize

Methods inherited from class java.util.AbstractCollection

addAll, contains, containsAll, remove, removeAll, retainAll, toArray, toArray

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection

addAll, contains, containsAll, equals, hashCode, remove, removeAll, retainAll, toArray, toArray

Field Detail

list

protected final List<E> list

List container

Constructor Detail

ListQueue

public ListQueue(List<E> list,
                 int maxSize)

Construct a new constrained ListQueue.

Parameters:

list - The list which will be used to store queued objects.

maxSize - The maximum size of the queue.

Throws:

IllegalArgumentException - List is null.

ListQueue

public ListQueue(int maxSize)

Construct a new constrained ListQueue using a LinkedList for a data-structure.

Parameters:

maxSize - The maximum size of the queue.

ListQueue

public ListQueue(List<E> list)

Construct a new unconstrained ListQueue.

Parameters:

list - The list which will be used to store queued objects.

Throws:

IllegalArgumentException - List is null

ListQueue

public ListQueue()

Construct a new unconstrained ListQueue using a LinkedList for a data-structure.

Method Detail

addLast

protected boolean addLast(E obj)

Appends the given element to the end of this list.

Specified by:

addLast in class AbstractQueue<E>

Parameters:

obj - Object to append.

Returns:

Per Collection.add(), we return a boolean to indicate if the object modified the collection.

removeFirst

protected E removeFirst()

Remove the first object in the queue.

Specified by:

removeFirst in class AbstractQueue<E>

Returns:

First object in the queue.

size

public int size()

Get the size of the queue.

Specified by:

size in interface Collection<E>

Specified by:

size in class AbstractCollection<E>

Returns:

The number of elements in the queue.

iterator

public Iterator<E> iterator()

Returns an iterator over the elements in this list in proper sequence.

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in class AbstractCollection<E>

Returns:

An iterator over the elements in this list in proper sequence.

getFront

public E getFront()
           throws EmptyCollectionException

Get the object at the front of the queue.

Returns:

Object at the front of the queue.

Throws:

EmptyCollectionException - The queue is empty.

getBack

public E getBack()
          throws EmptyCollectionException

Get the object at the back of the queue.

Returns:

Object at the back of the queue.

Throws:

EmptyCollectionException - The queue is empty.

reverseIterator

public Iterator<E> reverseIterator()

Returns an iterator over the elements in this list in reverse sequence.

Returns:

An iterator over the elements in this list in reverse sequence.

toString

public String toString()

Return a String representation of this queue.

Overrides:

toString in class AbstractCollection<E>

Returns:

String