io.netty.handler.codec

Class MessageToMessageEncoder<I>

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelOperationHandlerAdapter

io.netty.channel.ChannelOutboundMessageHandlerAdapter<I>

io.netty.handler.codec.MessageToMessageEncoder<I>

All Implemented Interfaces:

io.netty.channel.ChannelHandler, io.netty.channel.ChannelHandlerUtil.SingleOutboundMessageHandler<I>, io.netty.channel.ChannelOperationHandler, io.netty.channel.ChannelOutboundMessageHandler<I>

Direct Known Subclasses:

ProtobufEncoder

public abstract class MessageToMessageEncoder<I>
extends io.netty.channel.ChannelOutboundMessageHandlerAdapter<I>

ChannelOutboundMessageHandlerAdapter which encodes from one message to an other message For example here is an implementation which decodes an Integer to an String.

     public class IntegerToStringEncoder extends
             MessageToMessageEncoder<Integer> {
         public StringToIntegerDecoder() {
             super(String.class);
         }

         @Override
         public Object encode(ChannelHandlerContext ctx, Integer message)
                 throws Exception {
             return message.toString();
         }
     }
 

Nested Class Summary

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

io.netty.channel.ChannelHandler.Sharable

Field Summary

Fields inherited from class io.netty.channel.ChannelOutboundMessageHandlerAdapter

ABORT

Constructor Summary

Constructors

Constructor and Description
MessageToMessageEncoder()

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract Object	encode(io.netty.channel.ChannelHandlerContext ctx, I msg) Encode from one message to an other.
void	flush(io.netty.channel.ChannelHandlerContext ctx, I msg)

Methods inherited from class io.netty.channel.ChannelOutboundMessageHandlerAdapter

acceptOutboundMessage, beginFlush, endFlush, flush, freeOutboundBuffer, isCloseOnFailedFlush, newOutboundBuffer, setCloseOnFailedFlush

Methods inherited from class io.netty.channel.ChannelOperationHandlerAdapter

bind, close, connect, deregister, disconnect, read, sendFile

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

afterAdd, afterRemove, beforeAdd, beforeRemove, exceptionCaught

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.ChannelOperationHandler

bind, close, connect, deregister, disconnect, read, sendFile

Methods inherited from interface io.netty.channel.ChannelHandler

afterAdd, afterRemove, beforeAdd, beforeRemove, exceptionCaught

Constructor Detail

MessageToMessageEncoder

public MessageToMessageEncoder()

Method Detail

flush

public final void flush(io.netty.channel.ChannelHandlerContext ctx,
         I msg)
                 throws Exception

Throws:

Exception

encode

protected abstract Object encode(io.netty.channel.ChannelHandlerContext ctx,
            I msg)
                          throws Exception

Encode from one message to an other. This method will be called till either the MessageBuf has nothing left or till this method returns null.

Parameters:

ctx - the ChannelHandlerContext which this MessageToMessageEncoder belongs to

msg - the message to encode to an other one

Returns:

message the encoded message or null if more messages are needed be cause the implementation needs to do some kind of aggragation

Throws:

Exception - is thrown if an error accour