io.netty.handler.codec.string

Class LineEncoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelOutboundHandlerAdapter

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

io.netty.handler.codec.string.LineEncoder

All Implemented Interfaces:

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

@ChannelHandler.Sharable
public class LineEncoder
extends MessageToMessageEncoder<CharSequence>

Apply a line separator to the requested String and encode it into a ByteBuf. A typical setup for a text-based line protocol in a TCP/IP socket would be:

 ChannelPipeline pipeline = ...;

 // Decoders
 pipeline.addLast("frameDecoder", new LineBasedFrameDecoder(80));
 pipeline.addLast("stringDecoder", new StringDecoder(CharsetUtil.UTF_8));

 // Encoder
 pipeline.addLast("lineEncoder", new LineEncoder(LineSeparator.UNIX, CharsetUtil.UTF_8));
 

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

 void channelRead(ChannelHandlerContext ctx, String msg) {
     ch.write("Did you say '" + msg + "'?");
 }
 

Nested Class Summary

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

io.netty.channel.ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor and Description
LineEncoder() Creates a new instance with the current system line separator and UTF-8 charset encoding.
LineEncoder(Charset charset) Creates a new instance with the specified character set.
LineEncoder(LineSeparator lineSeparator) Creates a new instance with the specified line separator and UTF-8 charset encoding.
LineEncoder(LineSeparator lineSeparator, Charset charset) Creates a new instance with the specified line separator and character set.

Method Summary

Modifier and Type	Method and Description
protected void	encode(io.netty.channel.ChannelHandlerContext ctx, CharSequence msg, List<Object> out) Encode from one message to an other.

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

acceptOutboundMessage, write

Methods inherited from class io.netty.channel.ChannelOutboundHandlerAdapter

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

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, exceptionCaught, 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

exceptionCaught, handlerAdded, handlerRemoved

Constructor Detail

LineEncoder

public LineEncoder()

Creates a new instance with the current system line separator and UTF-8 charset encoding.

LineEncoder

public LineEncoder(LineSeparator lineSeparator)

Creates a new instance with the specified line separator and UTF-8 charset encoding.

LineEncoder

public LineEncoder(Charset charset)

Creates a new instance with the specified character set.

LineEncoder

public LineEncoder(LineSeparator lineSeparator,
                   Charset charset)

Creates a new instance with the specified line separator and character set.

Method Detail

encode

protected void encode(io.netty.channel.ChannelHandlerContext ctx,
                      CharSequence msg,
                      List<Object> out)
               throws Exception

Description copied from class: MessageToMessageEncoder

Encode from one message to an other. This method will be called for each written message that can be handled by this encoder.

Specified by:

encode in class MessageToMessageEncoder<CharSequence>

Parameters:

ctx - the ChannelHandlerContext which this MessageToMessageEncoder belongs to

msg - the message to encode to an other one

out - the List into which the encoded msg should be added needs to do some kind of aggregation

Throws:

Exception - is thrown if an error occurs