Package org.web3d.util

Class BlockingQueue

java.lang.Object

org.j3d.util.Queue

org.web3d.util.BlockingQueue

public class BlockingQueue
extends org.j3d.util.Queue

Blocking 'First In First Out' (FIFO) queue. Based on the simple Queue but can be used concurrently by separate threads. If there are not elements in the queue, getNext() will block until it is not empty. Taken from the VLC common code library http://www.vlc.com.au/common/ This software is released under the GNU LGPL

Version:

$Revision: 1.7 $

Author:

Justin Couch.

See Also:

• Queue

Constructor Summary

Constructors

Constructor	Description
BlockingQueue()	Constructor.

Method Summary

Modifier and Type	Method	Description
void	add(Object o)	Add an object to the end of the queue.
void	clear()	Clear the queue of items.
Object	getNext()	Return the next element from the front of the queue, and remove it from the queue.
boolean	hasNext()	Check if queue has more objects.
Object	peekNext()	Get the next element from the front of the queue.
void	purge()	Remove all elements from queue.
int	size()	Return the size of the queue.

Methods inherited from class org.j3d.util.Queue

remove

Methods inherited from class java.lang.Object

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

Constructor Details

BlockingQueue

public BlockingQueue()

Constructor. Create a simple queue.

Method Details

add

public void add(Object o)

Add an object to the end of the queue.

Overrides:

add in class org.j3d.util.Queue

Parameters:

o - Object to add.

getNext

public Object getNext()

Return the next element from the front of the queue, and remove it from the queue. Under normal circumstances this method will always return an object, blocking if it has to until something is available. However, sometimes the queue needs to close so we unblock the queue are return null instead.

Overrides:

getNext in class org.j3d.util.Queue

Returns:

element at the front of the queue, will block until queue is not empty.

peekNext

public Object peekNext()

Get the next element from the front of the queue.

Overrides:

peekNext in class org.j3d.util.Queue

Returns:

element at the front of the queue, null if empty.

hasNext

public boolean hasNext()

Check if queue has more objects.

Overrides:

hasNext in class org.j3d.util.Queue

Returns:

true if queue has more objects.

size

public int size()

Return the size of the queue.

Overrides:

size in class org.j3d.util.Queue

Returns:

size of queue.

purge

public void purge()

Remove all elements from queue. Also unblock those who are waiting for items in the queue. They leave the getNext() method with null.

clear

public void clear()

Clear the queue of items. If there are users of the class that are blocked while waiting for elements in the queue, they remain so.

Overrides:

clear in class org.j3d.util.Queue