io.netty.handler.codec.xml

Class XmlFrameDecoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.handler.codec.ByteToMessageDecoder

io.netty.handler.codec.xml.XmlFrameDecoder

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler

public class XmlFrameDecoder
extends ByteToMessageDecoder

A frame decoder for single separate XML based message streams.

A couple examples will better help illustrate what this decoder actually does.

Given an input array of bytes split over 3 frames like this:

 +-----+-----+-----------+
 | <an | Xml | Element/> |
 +-----+-----+-----------+
 

this decoder would output a single frame:

 +-----------------+
 | <anXmlElement/> |
 +-----------------+
 

Given an input array of bytes split over 5 frames like this:

 +-----+-----+-----------+-----+----------------------------------+
 | <an | Xml | Element/> | <ro | ot><child>content</child></root> |
 +-----+-----+-----------+-----+----------------------------------+
 

this decoder would output two frames:

 +-----------------+-------------------------------------+
 | <anXmlElement/> | <root><child>content</child></root> |
 +-----------------+-------------------------------------+
 

Please note that this decoder is not suitable for xml streaming protocols such as XMPP, where an initial xml element opens the stream and only gets closed at the end of the session, although this class could probably allow for such type of message flow with minor modifications.

Nested Class Summary

Nested classes/interfaces inherited from class io.netty.handler.codec.ByteToMessageDecoder

ByteToMessageDecoder.Cumulator

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

ChannelHandler.Sharable

Field Summary

Fields inherited from class io.netty.handler.codec.ByteToMessageDecoder

COMPOSITE_CUMULATOR, MERGE_CUMULATOR

Constructor Summary

Constructors

Constructor and Description
XmlFrameDecoder(int maxFrameLength)

Method Summary

Modifier and Type	Method and Description
protected void	decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) Decode the from one ByteBuf to an other.

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

actualReadableBytes, callDecode, channelInactive, channelRead, channelReadComplete, decodeLast, discardSomeReadBytes, handlerRemoved, handlerRemoved0, internalBuffer, isSingleDecode, setCumulator, setDiscardAfterReads, setSingleDecode, userEventTriggered

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelActive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, handlerAdded, 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

handlerAdded

Constructor Detail

XmlFrameDecoder

public XmlFrameDecoder(int maxFrameLength)

Method Detail

decode

protected void decode(ChannelHandlerContext ctx,
                      ByteBuf in,
                      List<Object> out)
               throws Exception

Description copied from class: ByteToMessageDecoder

Decode the from one ByteBuf to an other. This method will be called till either the input ByteBuf has nothing to read when return from this method or till nothing was read from the input ByteBuf.

Specified by:

decode in class ByteToMessageDecoder

Parameters:

ctx - the ChannelHandlerContext which this ByteToMessageDecoder belongs to

in - the ByteBuf from which to read data

out - the List to which decoded messages should be added

Throws:

Exception - is thrown if an error occurs