org.jboss.netty.handler.codec.string

Class StringEncoder

java.lang.Object

org.jboss.netty.handler.codec.oneone.OneToOneEncoder

org.jboss.netty.handler.codec.string.StringEncoder

All Implemented Interfaces:

ChannelDownstreamHandler, ChannelHandler

@ChannelHandler.Sharable
public class StringEncoder
extends OneToOneEncoder

Encodes the requested String into a ChannelBuffer. A typical setup for a text-based line protocol in a TCP/IP socket would be:

 ChannelPipeline pipeline = ...;

 // Decoders
 pipeline.addLast("frameDecoder", new DelimiterBasedFrameDecoder(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");
 }
 

Nested Class Summary

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

ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor and Description
StringEncoder() Creates a new instance with the current system character set.
StringEncoder(Charset charset) Creates a new instance with the specified character set.

Method Summary

Methods

Modifier and Type	Method and Description
protected Object	encode(ChannelHandlerContext ctx, Channel channel, Object msg) Transforms the specified message into another message and return the transformed message.

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

doEncode, handleDownstream

Methods inherited from class java.lang.Object

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

Constructor Detail

StringEncoder

public StringEncoder()

Creates a new instance with the current system character set.

StringEncoder

public StringEncoder(Charset charset)

Creates a new instance with the specified character set.

Method Detail

encode

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

Description copied from class: OneToOneEncoder

Transforms the specified message into another message and return the transformed message. Note that you can not return null, unlike you can in OneToOneDecoder.decode(ChannelHandlerContext, Channel, Object); you must return something, at least ChannelBuffers.EMPTY_BUFFER.

Specified by:

encode in class OneToOneEncoder

Throws:

Exception