Package io.netty.handler.codec
Class FixedLengthFrameDecoder
java.lang.Object
io.netty.channel.ChannelHandlerAdapter
io.netty.channel.ChannelInboundHandlerAdapter
io.netty.handler.codec.ByteToMessageDecoder
io.netty.handler.codec.FixedLengthFrameDecoder
- All Implemented Interfaces:
ChannelHandler
,ChannelInboundHandler
A decoder that splits the received
ByteBuf
s by the fixed number
of bytes. For example, if you received the following four fragmented packets:
+---+----+------+----+ | A | BC | DEFG | HI | +---+----+------+----+A
FixedLengthFrameDecoder
(3)
will decode them into the
following three packets with the fixed length:
+-----+-----+-----+ | ABC | DEF | GHI | +-----+-----+-----+
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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
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Field Summary
FieldsFields inherited from class io.netty.handler.codec.ByteToMessageDecoder
COMPOSITE_CUMULATOR, cumulation, MERGE_CUMULATOR
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Constructor Summary
Constructors -
Method Summary
Methods inherited from class io.netty.handler.codec.ByteToMessageDecoder
actualReadableBytes, callDecode, channelInactive, channelInputClosed, channelRead, channelReadComplete, decodeLast, decodeRemovalReentryProtection, discardSomeReadBytes, expandCumulation, fireChannelRead, fireChannelRead, 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
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Field Details
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frameLength
private final int frameLength
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Constructor Details
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FixedLengthFrameDecoder
public FixedLengthFrameDecoder(int frameLength) Creates a new instance.- Parameters:
frameLength
- the length of the frame
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Method Details
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decode
protected final void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws 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:
Exception
- is thrown if an error occurs
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decode
Create a frame out of theByteBuf
and return it.- Parameters:
ctx
- theChannelHandlerContext
which thisByteToMessageDecoder
belongs toin
- theByteBuf
from which to read data- Returns:
- frame the
ByteBuf
which represent the frame ornull
if no frame could be created. - Throws:
Exception
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