org.jboss.netty.handler.codec.string
Class StringDecoder

java.lang.Object
  org.jboss.netty.handler.codec.oneone.OneToOneDecoder
      org.jboss.netty.handler.codec.string.StringDecoder

All Implemented Interfaces:

ChannelHandler, ChannelUpstreamHandler

@ChannelHandler.Sharable
public class StringDecoder
extends OneToOneDecoder

Decodes a received ChannelBuffer into a String. Please note that this decoder must be used with a proper FrameDecoder such as DelimiterBasedFrameDecoder if you are using a stream-based transport such as TCP/IP. A typical setup for a text-based line protocol in a TCP/IP socket would be:

 ChannelPipeline pipeline = ...;

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

 // Encoder
 pipeline.addLast("stringEncoder", new StringEncoder(CharsetUtil.UTF_8));
 

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

 void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
     String msg = (String) e.getMessage();
     ch.write("Did you say '" + msg + "'?\n");
 }
 

Version:

$Rev:231 $, $Date:2008-06-12 16:44:50 +0900 (목, 12 6월 2008) $

Author:

The Netty Project, Trustin Lee

Nested Class Summary

Nested classes/interfaces inherited from interface org.jboss.netty.channel.ChannelHandler

ChannelHandler.Sharable

Constructor Summary

StringDecoder()
Creates a new instance with the current system character set.

StringDecoder(Charset charset)
Creates a new instance with the specified character set.

StringDecoder(String charsetName)
Deprecated. Use StringDecoder(Charset) instead.

Method Summary

protected Object

decode(ChannelHandlerContext ctx, Channel channel, Object msg) Transforms the specified received message into another message and return the transformed message.

Methods inherited from class org.jboss.netty.handler.codec.oneone.OneToOneDecoder

handleUpstream

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StringDecoder

public StringDecoder()

Creates a new instance with the current system character set.

StringDecoder

public StringDecoder(Charset charset)

Creates a new instance with the specified character set.

StringDecoder

@Deprecated
public StringDecoder(String charsetName)

Deprecated. Use StringDecoder(Charset) instead.

Method Detail

decode

protected Object decode(ChannelHandlerContext ctx,
                        Channel channel,
                        Object msg)
                 throws Exception

Description copied from class: OneToOneDecoder

Transforms the specified received message into another message and return the transformed message. Return null if the received message is supposed to be discarded.

Specified by:

decode in class OneToOneDecoder

Throws:

Exception