Package 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> | +-----------------+-------------------------------------+
The byte stream is expected to be in UTF-8 character encoding or ASCII. The current implementation uses directbyte
tochar
cast and then compares thatchar
to a few low range ASCII characters like'<'
,'>'
or'/'
. UTF-8 is not using low range [0..0x7F] byte values for multibyte codepoint representations therefore fully supported by this implementation. 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 Description XmlFrameDecoder(int maxFrameLength)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description protected void
decode(ChannelHandlerContext ctx, ByteBuf in, java.util.List<java.lang.Object> out)
Decode the from oneByteBuf
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
-
-
-
-
Method Detail
-
decode
protected void decode(ChannelHandlerContext ctx, ByteBuf in, java.util.List<java.lang.Object> out) throws java.lang.Exception
Description copied from class:ByteToMessageDecoder
Decode the from oneByteBuf
to an other. This method will be called till either the inputByteBuf
has nothing to read when return from this method or till nothing was read from the inputByteBuf
.- Specified by:
decode
in classByteToMessageDecoder
- Parameters:
ctx
- theChannelHandlerContext
which thisByteToMessageDecoder
belongs toin
- theByteBuf
from which to read dataout
- theList
to which decoded messages should be added- Throws:
java.lang.Exception
- is thrown if an error occurs
-
-