org.springframework.integration.channel
Class QueueChannel

java.lang.Object
  org.springframework.integration.channel.AbstractMessageChannel
      org.springframework.integration.channel.AbstractPollableChannel
          org.springframework.integration.channel.QueueChannel

All Implemented Interfaces:

org.springframework.beans.factory.BeanNameAware, PollableChannel, MessageChannel

Direct Known Subclasses:

PriorityChannel, RendezvousChannel

public class QueueChannel
extends AbstractPollableChannel

Simple implementation of a message channel. Each Message is placed in a BlockingQueue whose capacity may be specified upon construction. The capacity must be a positive integer value. For a zero-capacity version based upon a SynchronousQueue, consider the RendezvousChannel.

Author:

Mark Fisher

Nested Class Summary

Nested classes/interfaces inherited from class org.springframework.integration.channel.AbstractMessageChannel

AbstractMessageChannel.ChannelInterceptorList

Constructor Summary

QueueChannel()
Create a channel with "unbounded" queue capacity.

QueueChannel(java.util.concurrent.BlockingQueue<Message<?>> queue)
Create a channel with the specified queue.

QueueChannel(int capacity)
Create a channel with the specified queue capacity.

Method Summary

java.util.List<Message<?>>	clear() Remove all Messages from this channel.
protected Message<?>	doReceive(long timeout) Subclasses must implement this method.
protected boolean	doSend(Message<?> message, long timeout) Subclasses must implement this method.
int	getMesssageCount()
int	getRemainingCapacity()
java.util.List<Message<?>>	purge(MessageSelector selector) Remove any Messages that are not accepted by the provided selector.

Methods inherited from class org.springframework.integration.channel.AbstractPollableChannel

receive, receive

Methods inherited from class org.springframework.integration.channel.AbstractMessageChannel

addInterceptor, getInterceptors, getName, send, send, setBeanName, setInterceptors, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.integration.core.MessageChannel

getName, send, send

Constructor Detail

QueueChannel

public QueueChannel(java.util.concurrent.BlockingQueue<Message<?>> queue)

Create a channel with the specified queue.

QueueChannel

public QueueChannel(int capacity)

Create a channel with the specified queue capacity.

QueueChannel

public QueueChannel()

Create a channel with "unbounded" queue capacity. The actual capacity value is Integer.MAX_VALUE. Note that a bounded queue is recommended, since an unbounded queue may lead to OutOfMemoryErrors.

Method Detail

doSend

protected boolean doSend(Message<?> message,
                         long timeout)

Description copied from class: AbstractMessageChannel

Subclasses must implement this method. A non-negative timeout indicates how long to wait if the channel is at capacity (if the value is 0, it must return immediately with or without success). A negative timeout value indicates that the method should block until either the message is accepted or the blocking thread is interrupted.

Specified by:

doSend in class AbstractMessageChannel

doReceive

protected Message<?> doReceive(long timeout)

Description copied from class: AbstractPollableChannel

Subclasses must implement this method. A non-negative timeout indicates how long to wait if the channel is empty (if the value is 0, it must return immediately with or without success). A negative timeout value indicates that the method should block until either a message is available or the blocking thread is interrupted.

Specified by:

doReceive in class AbstractPollableChannel

clear

public java.util.List<Message<?>> clear()

Description copied from interface: PollableChannel

Remove all Messages from this channel.

purge

public java.util.List<Message<?>> purge(MessageSelector selector)

Description copied from interface: PollableChannel

Remove any Messages that are not accepted by the provided selector.

getMesssageCount

public int getMesssageCount()

getRemainingCapacity

public int getRemainingCapacity()