io.netty.handler.codec.protobuf

Class ProtobufEncoder

java.lang.Object

io.netty.channel.ChannelOperationHandlerAdapter

io.netty.channel.ChannelOutboundHandlerAdapter

io.netty.channel.ChannelOutboundMessageHandlerAdapter<I>

io.netty.handler.codec.MessageToMessageEncoder<Object,ByteBuf>

io.netty.handler.codec.protobuf.ProtobufEncoder

All Implemented Interfaces:

ChannelHandler, ChannelOperationHandler, ChannelOutboundHandler, ChannelOutboundMessageHandler<Object>

@ChannelHandler.Sharable
public class ProtobufEncoder
extends MessageToMessageEncoder<Object,ByteBuf>

Encodes the requested Google Protocol Buffers Message and MessageLite into a ByteBuf. A typical setup for TCP/IP would be:

 ChannelPipeline pipeline = ...;

 // Decoders
 pipeline.addLast("frameDecoder",
                  new LengthFieldBasedFrameDecoder(1048576, 0, 4, 0, 4));
 pipeline.addLast("protobufDecoder",
                  new ProtobufDecoder(MyMessage.getDefaultInstance()));

 // Encoder
 pipeline.addLast("frameEncoder", new LengthFieldPrepender(4));
 pipeline.addLast("protobufEncoder", new ProtobufEncoder());
 

and then you can use a MyMessage instead of a ByteBuf as a message:

 void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
     MyMessage req = (MyMessage) e.getMessage();
     MyMessage res = MyMessage.newBuilder().setText(
                               "Did you say '" + req.getText() + "'?").build();
     ch.write(res);
 }
 

Nested Class Summary

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

ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor and Description
ProtobufEncoder()

Method Summary

Methods

Modifier and Type	Method and Description
ByteBuf	encode(ChannelHandlerContext ctx, Object msg)
boolean	isEncodable(Object msg) Returns true if and only if the specified message can be encoded by this encoder.

Methods inherited from class io.netty.handler.codec.MessageToMessageEncoder

flush

Methods inherited from class io.netty.channel.ChannelOutboundMessageHandlerAdapter

newOutboundBuffer

Methods inherited from class io.netty.channel.ChannelOperationHandlerAdapter

afterAdd, afterRemove, beforeAdd, beforeRemove, bind, close, connect, deregister, disconnect, exceptionCaught, userEventTriggered

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

Methods inherited from interface io.netty.channel.ChannelHandler

afterAdd, afterRemove, beforeAdd, beforeRemove, exceptionCaught, userEventTriggered

Constructor Detail

ProtobufEncoder

public ProtobufEncoder()

Method Detail

isEncodable

public boolean isEncodable(Object msg)
                    throws Exception

Description copied from class: MessageToMessageEncoder

Returns true if and only if the specified message can be encoded by this encoder.

Overrides:

isEncodable in class MessageToMessageEncoder<Object,ByteBuf>

Parameters:

msg - the message

Throws:

Exception

encode

public ByteBuf encode(ChannelHandlerContext ctx,
             Object msg)
               throws Exception

Specified by:

encode in class MessageToMessageEncoder<Object,ByteBuf>

Throws:

Exception