Package io.lettuce.core.pubsub

Class PubSubCommandHandler<K,V>

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.channel.ChannelDuplexHandler

io.lettuce.core.protocol.CommandHandler

io.lettuce.core.pubsub.PubSubCommandHandler<K,V>

Type Parameters:

K - Key type.

V - Value type.

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler, ChannelOutboundHandler

public class PubSubCommandHandler<K,V>
extends CommandHandler

A netty ChannelHandler responsible for writing Redis Pub/Sub commands and reading the response stream from the server. PubSubCommandHandler accounts for Pub/Sub message notification calling back PubSubEndpoint.notifyMessage(PubSubMessage). Redis responses can be interleaved in the sense that a response contains a Pub/Sub message first, then a command response. Possible interleave is introspected via PubSubCommandHandler.ResponseHeaderReplayOutput and decoding hooks.

Author:

Will Glozer, Mark Paluch

Nested Class Summary

Nested classes/interfaces inherited from class io.lettuce.core.protocol.CommandHandler

CommandHandler.LifecycleState

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

ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor	Description
PubSubCommandHandler(ClientOptions clientOptions, ClientResources clientResources, RedisCodec<K,V> codec, PubSubEndpoint<K,V> endpoint)	Initialize a new instance.

Method Summary

Modifier and Type	Method	Description
protected void	afterDecode(ChannelHandlerContext ctx, RedisCommand<?,?,?> command)	Hook method called after command completion.
protected boolean	canComplete(RedisCommand<?,?,?> command)	Decoding hook: Can the command be completed.
protected boolean	canDecode(ByteBuf buffer)	Decoding hook: Can the buffer be decoded to a command.
void	channelInactive(ChannelHandlerContext ctx)
protected void	complete(RedisCommand<?,?,?> command)	Decoding hook: Complete a command.
protected void	decode(ChannelHandlerContext ctx, ByteBuf buffer)
protected CommandOutput<?,?,?>	getCommandOutput(RedisCommand<?,?,?> command)	Decoding hook: Retrieve CommandOutput for RedisCommand decoding.
protected void	notifyPushListeners(PushMessage notification)

Methods inherited from class io.lettuce.core.protocol.CommandHandler

channelActive, channelRead, channelRegistered, channelUnregistered, decode, decode, drainQueue, exceptionCaught, getChannelId, getEndpoint, getStack, getState, isClosed, isPushDecode, setState, userEventTriggered, write

Methods inherited from class io.netty.channel.ChannelDuplexHandler

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

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelReadComplete, channelWritabilityChanged

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

PubSubCommandHandler

public PubSubCommandHandler(ClientOptions clientOptions,
                            ClientResources clientResources,
                            RedisCodec<K,V> codec,
                            PubSubEndpoint<K,V> endpoint)

Initialize a new instance.

Parameters:

clientOptions - client options for this connection, must not be null

clientResources - client resources for this connection

codec - Codec.

endpoint - the Pub/Sub endpoint for Pub/Sub callback.

Method Detail

channelInactive

public void channelInactive(ChannelHandlerContext ctx)
                     throws Exception

Specified by:

channelInactive in interface ChannelInboundHandler

Overrides:

channelInactive in class CommandHandler

Throws:

Exception

See Also:

ChannelInboundHandlerAdapter.channelInactive(io.netty.channel.ChannelHandlerContext)

decode

protected void decode(ChannelHandlerContext ctx,
                      ByteBuf buffer)
               throws InterruptedException

Overrides:

decode in class CommandHandler

Throws:

InterruptedException

canDecode

protected boolean canDecode(ByteBuf buffer)

Description copied from class: CommandHandler

Decoding hook: Can the buffer be decoded to a command.

Overrides:

canDecode in class CommandHandler

Returns:

canComplete

protected boolean canComplete(RedisCommand<?,?,?> command)

Description copied from class: CommandHandler

Decoding hook: Can the command be completed.

Overrides:

canComplete in class CommandHandler

Returns:

complete

protected void complete(RedisCommand<?,?,?> command)

Description copied from class: CommandHandler

Decoding hook: Complete a command.

Overrides:

complete in class CommandHandler

See Also:

RedisCommand.complete()

getCommandOutput

protected CommandOutput<?,?,?> getCommandOutput(RedisCommand<?,?,?> command)

Description copied from class: CommandHandler

Decoding hook: Retrieve CommandOutput for RedisCommand decoding.

Overrides:

getCommandOutput in class CommandHandler

Returns:

See Also:

RedisCommand.getOutput()

notifyPushListeners

protected void notifyPushListeners(PushMessage notification)

Overrides:

notifyPushListeners in class CommandHandler

afterDecode

protected void afterDecode(ChannelHandlerContext ctx,
                           RedisCommand<?,?,?> command)

Description copied from class: CommandHandler

Hook method called after command completion.

Overrides:

afterDecode in class CommandHandler