org.jboss.netty.channel.socket.oio
Class OioDatagramChannelFactory

java.lang.Object
  extended by org.jboss.netty.channel.socket.oio.OioDatagramChannelFactory
All Implemented Interfaces:
ChannelFactory, DatagramChannelFactory, ExternalResourceReleasable

public class OioDatagramChannelFactory
extends Object
implements DatagramChannelFactory

A DatagramChannelFactory which creates a blocking I/O based DatagramChannel. It utilizes the good old blocking I/O API which has support for multicast.

How threads work

There is only one type of threads in OioDatagramChannelFactory; worker threads.

Worker threads

Each Channel has a dedicated worker thread, just like a traditional blocking I/O thread model.

Life cycle of threads and graceful shutdown

Worker threads are acquired from the Executor which was specified when a OioDatagramChannelFactory was created (i.e. workerExecutor.) Therefore, you should make sure the specified Executor is able to lend the sufficient number of threads.

Worker threads are acquired lazily, and then released when there's nothing left to process. All the related resources are also released when the worker threads are released. Therefore, to shut down a service gracefully, you should do the following:

  1. close all channels created by the factory usually using ChannelGroup.close(), and
  2. call releaseExternalResources().
Please make sure not to shut down the executor until all channels are closed. Otherwise, you will end up with a RejectedExecutionException and the related resources might not be released properly.

Limitation

A DatagramChannel created by this factory does not support asynchronous operations. Any I/O requests such as "write" will be performed in a blocking manner.

Version:
$Rev: 2080 $, $Date: 2010-01-26 18:04:19 +0900 (Tue, 26 Jan 2010) $
Author:
The Netty Project, Trustin Lee

Constructor Summary
OioDatagramChannelFactory(Executor workerExecutor)
          Creates a new instance.
 
Method Summary
 DatagramChannel newChannel(ChannelPipeline pipeline)
          Creates and opens a new Channel and attaches the specified ChannelPipeline to the new Channel.
 void releaseExternalResources()
          Releases the external resources that this factory depends on to function.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

OioDatagramChannelFactory

public OioDatagramChannelFactory(Executor workerExecutor)
Creates a new instance.

Parameters:
workerExecutor - the Executor which will execute the I/O worker threads
Method Detail

newChannel

public DatagramChannel newChannel(ChannelPipeline pipeline)
Description copied from interface: ChannelFactory
Creates and opens a new Channel and attaches the specified ChannelPipeline to the new Channel.

Specified by:
newChannel in interface ChannelFactory
Specified by:
newChannel in interface DatagramChannelFactory
Parameters:
pipeline - the ChannelPipeline which is going to be attached to the new Channel
Returns:
the newly open channel

releaseExternalResources

public void releaseExternalResources()
Description copied from interface: ChannelFactory
Releases the external resources that this factory depends on to function. An external resource is a resource that this factory didn't create by itself. For example, Executors that you specified in the factory constructor are external resources. You can call this method to release all external resources conveniently when the resources are not used by this factory or any other part of your application. An unexpected behavior will be resulted in if the resources are released when there's an open channel which is managed by this factory.

Specified by:
releaseExternalResources in interface ChannelFactory
Specified by:
releaseExternalResources in interface ExternalResourceReleasable


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