Package org.jivesoftware.openfire.nio

Class NettyIdleStateKeepAliveHandler

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.channel.ChannelDuplexHandler

org.jivesoftware.openfire.nio.NettyIdleStateKeepAliveHandler

All Implemented Interfaces:

io.netty.channel.ChannelHandler, io.netty.channel.ChannelInboundHandler, io.netty.channel.ChannelOutboundHandler

public class NettyIdleStateKeepAliveHandler
extends io.netty.channel.ChannelDuplexHandler

A NettyIdleStateKeepAliveHandler listens for IdleStateEvents triggered by an IdleStateHandler. When invoked, the existence of a flag on the ChannelHandlerContext is determined. If this flag does not exist, then a keep-alive check if performed and the flag is set. If the does exist, then it is assumed that the peer failed the keep-alive check and the connection should be closed. The keep-alive check is implemented as an XMPP ping request. XMPP entities must respond with either an IQ result or an IQ error (feature-unavailable) stanza upon receiving the XMPP ping stanza. Both responses will be received by Openfire. As any inbound data will cause the flag to be reset, the connection will no longer be deemed 'idle'. Entities that do not respond to the IQ Ping stanzas can be considered dead, and their connection will be closed when the IdleStateHandler triggers the second idle event in a row. Note that whitespace pings that are sent by XMPP entities will also cause the connection idle count to be reset.

Author:

Alex Gidman

See Also:

IdleStateEvent, IdleStateHandler

Nested Class Summary

Nested classes/interfaces inherited from interface io.netty.channel.ChannelHandler

io.netty.channel.ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor	Description
NettyIdleStateKeepAliveHandler(boolean clientConnection)

Method Summary

Modifier and Type	Method	Description
void	userEventTriggered(io.netty.channel.ChannelHandlerContext ctx, Object evt)	Processes IdleStateEvents triggered by an IdleStateHandler.

Methods inherited from class io.netty.channel.ChannelDuplexHandler

bind, close, connect, deregister, disconnect, flush, read, write

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelActive, channelInactive, channelRead, channelReadComplete, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, handlerAdded, handlerRemoved, isSharable

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.netty.channel.ChannelHandler

handlerAdded, handlerRemoved

Constructor Detail

NettyIdleStateKeepAliveHandler

public NettyIdleStateKeepAliveHandler(boolean clientConnection)

Method Detail

userEventTriggered

public void userEventTriggered(io.netty.channel.ChannelHandlerContext ctx,
                               Object evt)
                        throws Exception

Processes IdleStateEvents triggered by an IdleStateHandler. If the IdleStateEvent is an idle read state, the Netty channel is closed. If the IdleStateEvent is an idle write state, an XMPP ping request is sent to the remote entity.

Specified by:

userEventTriggered in interface io.netty.channel.ChannelInboundHandler

Overrides:

userEventTriggered in class io.netty.channel.ChannelInboundHandlerAdapter

Parameters:

ctx - ChannelHandlerContext

evt - Event caught, expect IdleStateEvent

Throws:

Exception - when attempting to deliver ping packet