org.jboss.util.collection
Class AbstractQueue

java.lang.Object
  java.util.AbstractCollection
      org.jboss.util.collection.AbstractQueue

All Implemented Interfaces:

java.util.Collection, Queue (src)

Direct Known Subclasses:

ListQueue (src)

public abstract class AbstractQueue

extends java.util.AbstractCollection

implements Queue (src)

An abstract implementation of a Queue. Sub-classes must provide methods for addLast(Object) and removeFirst().

DEFAULT_MAXIMUM_SIZE

public static int DEFAULT_MAXIMUM_SIZE

Default maximum queue size

maximumSize

protected int maximumSize

Maximum queue size

AbstractQueue

protected AbstractQueue()

Initializes the AbstractQueue.

AbstractQueue

protected AbstractQueue(int maxSize)

Initializes the AbstractQueue.

Parameters:

maxSize - Maximum queue size.

Throws:

java.lang.IllegalArgumentException - Illegal size.

getMaximumSize

public int getMaximumSize()

Get the maximum size of the queue.

Specified by:

getMaximumSize in interface Queue (src)

Returns:

Maximum queue size or Queue.UNLIMITED_MAXIMUM_SIZE.

setMaximumSize

public void setMaximumSize(int size)

Set the maximum size of the queue

Specified by:

setMaximumSize in interface Queue (src)

Parameters:

size - New maximim queue size or Queue.UNLIMITED_MAXIMUM_SIZE.

Throws:

java.lang.IllegalArgumentException - Illegal size.

isFull

public boolean isFull()

Check if the queue is full.

Specified by:

isFull in interface Queue (src)

Returns:

True if the queue is full.

isEmpty

public boolean isEmpty()

Check if the queue is empty.

Specified by:

isEmpty in interface Queue (src)

Returns:

True if the queue is empty.

add

public boolean add(java.lang.Object obj)
            throws FullCollectionException (src) 

Append and object to the underling list.

Specified by:

add in interface Queue (src)

Parameters:

obj - Object to enqueue.

Returns:

True if collection was modified.

Throws:

FullCollectionException (src) - The queue is full.

remove

public java.lang.Object remove()
                        throws EmptyCollectionException (src) 

Remove and return the first object in the queue.

Specified by:

remove in interface Queue (src)

Returns:

Dequeued object.

Throws:

EmptyCollectionException (src) - The queue is empty.

clear

public void clear()

Removes all of the elements from this queue

Specified by:

clear in interface java.util.Collection

addLast

protected abstract boolean addLast(java.lang.Object obj)

Appends the given element to the end of the queue

Parameters:

obj - Object to append

Returns:

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

removeFirst

protected abstract java.lang.Object removeFirst()

Remove the first object in the queue

Returns:

First object in the queue