io.netty.handler.codec.string

Class StringEncoder

java.lang.Object

io.netty.channel.ChannelOperationHandlerAdapter

io.netty.channel.ChannelOutboundHandlerAdapter

io.netty.channel.ChannelOutboundMessageHandlerAdapter<I>

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

io.netty.handler.codec.string.StringEncoder

All Implemented Interfaces:

ChannelHandler, ChannelOperationHandler, ChannelOutboundHandler, ChannelOutboundMessageHandler<String>

@ChannelHandler.Sharable
public class StringEncoder
extends MessageToMessageEncoder<String,ByteBuf>

Encodes the requested String 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 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 ByteBuf 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 io.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
ByteBuf	encode(ChannelHandlerContext ctx, String 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

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

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<String,ByteBuf>

Parameters:

msg - the message

Throws:

Exception

encode

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

Specified by:

encode in class MessageToMessageEncoder<String,ByteBuf>

Throws:

Exception