org.perfectjpattern.core.structural.adapter
Class List2QueueAdapter<E>

java.lang.Object
  org.perfectjpattern.core.structural.AbstractSurrogate<T,A>
      org.perfectjpattern.core.structural.adapter.Adapter<Queue<E>,List<E>>
          org.perfectjpattern.core.structural.adapter.List2QueueAdapter<E>

Type Parameters:

E - Type of the Queue elements

All Implemented Interfaces:

InvocationHandler, IAdapter<Queue<E>,List<E>>, ISurrogate<Queue<E>>

public class List2QueueAdapter<E>
extends Adapter<Queue<E>,List<E>>

Adapter that provides a Queue based on a List implementation. That is, it adapts the List to behave and look like a Queue. Please note that this is not an exhaustive implementation of Queue nor it replaces the proper JDK Queue implementations. The purpose of this Adapter is only to demonstrate:

• How to use PerfectJPattern's Adapter implementation to adapt an implementation to a given target interface
• How the componentized Adapter facilitates adapting types by means of:
  • Automatically delegating to the adapter implementation calls made to the target interface in this case e.g. remove(), poll() element() peek()
  • Otherwise automatically delegating to the Adaptee implementation using a specified IAdaptingStrategy in this case NameMatchAdaptingStrategy where it maps e.g. offer(Object) to ArrayList.add(Object)

Noteworthy is how this implementation did NOT have to provide a full blown implementation of all of the Target Queue interface methods e.g. Collection.addAll(Collection) or Collection.toArray() as the call forwarding is automatically handled by PerfectJPattern's Adapter

Version:

$Revision: 1.0 $Date: Feb 5, 2009 8:55:42 PM $

Author:

Giovanni Azua

Constructor Summary

List2QueueAdapter(List<E> anAdaptee)
Constructs a List2QueueAdapter from the underlying Adaptee List implementation.

Method Summary

E	element() Retrieves, but does not remove, the head of this queue.
E	peek() Retrieves, but does not remove, the head of this queue, or returns null if this queue is empty.
E	poll() Retrieves and removes the head of this queue, or returns null if this queue is empty.
E	remove() Retrieves and removes the head of this queue.

Methods inherited from class org.perfectjpattern.core.structural.adapter.Adapter

getAdaptee, getTarget, invokeUnderlying, setAdaptingStrategy

Methods inherited from class org.perfectjpattern.core.structural.AbstractSurrogate

equals, getComponent, getComponentClass, getUnderlying, hashCode, invoke

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.perfectjpattern.core.api.structural.ISurrogate

getComponent

Methods inherited from interface java.lang.reflect.InvocationHandler

invoke

Constructor Detail

List2QueueAdapter

public List2QueueAdapter(List<E> anAdaptee)
                  throws IllegalArgumentException

Constructs a List2QueueAdapter from the underlying Adaptee List implementation.

Parameters:

anAdaptee - The Adaptee List implementation to adapt

Throws:

IllegalArgumentException - 'anAdaptee' must not be null

Method Detail

remove

public E remove()
         throws NoSuchElementException

Retrieves and removes the head of this queue. This method differs from poll only in that it throws an exception if this queue is empty.

Returns:

the head of this queue

Throws:

NoSuchElementException - if this queue is empty

poll

public E poll()

Retrieves and removes the head of this queue, or returns null if this queue is empty.

Returns:

the head of this queue, or null if this queue is empty

element

public E element()

Retrieves, but does not remove, the head of this queue. This method differs from peek only in that it throws an exception if this queue is empty.

Returns:

the head of this queue

Throws:

NoSuchElementException - if this queue is empty

peek

public E peek()

Retrieves, but does not remove, the head of this queue, or returns null if this queue is empty.

Returns:

the head of this queue, or null if this queue is empty