org.apache.excalibur.event.impl
Class DefaultQueue

java.lang.Object
  org.apache.excalibur.event.impl.AbstractQueue
      org.apache.excalibur.event.impl.DefaultQueue

All Implemented Interfaces:

Queue, Sink, Source

public final class DefaultQueue
extends AbstractQueue

The default queue implementation is a variable size queue. This queue is thread safe, however the overhead in synchronization costs a few extra milliseconds.

Author:

Avalon Development Team

Field Summary

protected int

m_reserve

Fields inherited from class org.apache.excalibur.event.impl.AbstractQueue

EMPTY_ARRAY, m_interceptor, m_predicate, m_timeout

Fields inherited from interface org.apache.excalibur.event.Queue

ROLE

Constructor Summary

DefaultQueue()
Create an unbounded DefaultQueue.

DefaultQueue(EnqueuePredicate predicate)

DefaultQueue(int size)
Construct a new DefaultQueue with the specified number of elements.

Method Summary

Object	dequeue()
Object[]	dequeue(int numElements)
Object[]	dequeueAll()
void	enqueue(Object element)
void	enqueue(Object[] elements)
int	maxSize() Return the maximum number of elements that will fit in the Queue.
PreparedEnqueue	prepareEnqueue(Object[] elements)
int	size() Return the number of elements currently in the Queue.
boolean	tryEnqueue(Object element)

Methods inherited from class org.apache.excalibur.event.impl.AbstractQueue

block, canAccept, getDequeueInterceptor, getEnqueuePredicate, isFull, setDequeueInterceptor, setEnqueuePredicate, setTimeout

Methods inherited from class java.lang.Object

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

Field Detail

m_reserve

protected int m_reserve

Constructor Detail

DefaultQueue

public DefaultQueue(int size)

Construct a new DefaultQueue with the specified number of elements. if the number of elements is greater than zero, then the Queue is bounded by that number. Otherwise, the Queue is not bounded at all.

Parameters:

size - The maximum number of elements in the Queue. Any number less than 1 means there is no limit.

DefaultQueue

public DefaultQueue(EnqueuePredicate predicate)

DefaultQueue

public DefaultQueue()

Create an unbounded DefaultQueue.

Method Detail

size

public int size()

Return the number of elements currently in the Queue.

Returns:

int representing the number of elements (including the reserved ones).

maxSize

public int maxSize()

Return the maximum number of elements that will fit in the Queue. A number below 1 indecates an unbounded Queue, which means there is no limit.

Specified by:

maxSize in interface Sink

Overrides:

maxSize in class AbstractQueue

Returns:

int representing the maximum number of elements

prepareEnqueue

public PreparedEnqueue prepareEnqueue(Object[] elements)
                               throws SinkException

Throws:

SinkException

tryEnqueue

public boolean tryEnqueue(Object element)

enqueue

public void enqueue(Object[] elements)
             throws SinkException

Throws:

SinkException

enqueue

public void enqueue(Object element)
             throws SinkException

Throws:

SinkException

dequeue

public Object[] dequeue(int numElements)

dequeueAll

public Object[] dequeueAll()

dequeue

public Object dequeue()