io.netty.channel

Class SimpleChannelInboundHandler<I>

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.channel.SimpleChannelInboundHandler<I>

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler

public abstract class SimpleChannelInboundHandler<I>
extends ChannelInboundHandlerAdapter

ChannelInboundHandlerAdapter which allows to explicit only handle a specific type of messages. For example here is an implementation which only handle String messages.

     public class StringHandler extends
             SimpleChannelInboundHandler<String> {

         @Override
         protected void channelRead0(ChannelHandlerContext ctx, String message)
                 throws Exception {
             System.out.println(message);
         }
     }
 

Be aware that depending of the constructor parameters it will release all handled messages by passing them to ReferenceCountUtil.release(Object). In this case you may need to use ReferenceCountUtil.retain(Object) if you pass the object to the next handler in the ChannelPipeline.

Forward compatibility notice

Please keep in mind that #channelRead0(ChannelHandlerContext, I) will be renamed to messageReceived(ChannelHandlerContext, I) in 5.0.

Nested Class Summary

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

ChannelHandler.Sharable

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SimpleChannelInboundHandler()
protected	SimpleChannelInboundHandler(boolean autoRelease) Create a new instance which will try to detect the types to match out of the type parameter of the class.
protected	SimpleChannelInboundHandler(Class<? extends I> inboundMessageType)
protected	SimpleChannelInboundHandler(Class<? extends I> inboundMessageType, boolean autoRelease) Create a new instance

Method Summary

Methods

Modifier and Type	Method and Description
boolean	acceptInboundMessage(Object msg) Returns true if the given message should be handled.
void	channelRead(ChannelHandlerContext ctx, Object msg) Calls ChannelHandlerContext.fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.
protected abstract void	channelRead0(ChannelHandlerContext ctx, I msg) Please keep in mind that this method will be renamed to messageReceived(ChannelHandlerContext, I) in 5.0.

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

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

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

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

SimpleChannelInboundHandler

protected SimpleChannelInboundHandler()

See Also:

#SimpleChannelInboundHandler(boolean)} with {@code true} as boolean parameter.

SimpleChannelInboundHandler

protected SimpleChannelInboundHandler(boolean autoRelease)

Create a new instance which will try to detect the types to match out of the type parameter of the class.

Parameters:

autoRelease - true if handled messages should be released automatically by passing them to ReferenceCountUtil.release(Object).

SimpleChannelInboundHandler

protected SimpleChannelInboundHandler(Class<? extends I> inboundMessageType)

See Also:

#SimpleChannelInboundHandler(Class, boolean)} with {@code true} as boolean value.

SimpleChannelInboundHandler

protected SimpleChannelInboundHandler(Class<? extends I> inboundMessageType,
                           boolean autoRelease)

Create a new instance

Parameters:

inboundMessageType - The type of messages to match

autoRelease - true if handled messages should be released automatically by passing them to ReferenceCountUtil.release(Object).

Method Detail

acceptInboundMessage

public boolean acceptInboundMessage(Object msg)
                             throws Exception

Returns true if the given message should be handled. If false it will be passed to the next ChannelInboundHandler in the ChannelPipeline.

Throws:

Exception

channelRead

public void channelRead(ChannelHandlerContext ctx,
               Object msg)
                 throws Exception

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

channelRead in interface ChannelInboundHandler

Overrides:

channelRead in class ChannelInboundHandlerAdapter

Throws:

Exception

channelRead0

protected abstract void channelRead0(ChannelHandlerContext ctx,
                I msg)
                              throws Exception

Please keep in mind that this method will be renamed to messageReceived(ChannelHandlerContext, I) in 5.0. Is called for each message of type I.

Parameters:

ctx - the ChannelHandlerContext which this SimpleChannelInboundHandler belongs to

msg - the message to handle

Throws:

Exception - is thrown if an error occurred