Module io.netty5.codec

Package io.netty5.handler.codec

Class FixedLengthFrameDecoder

java.lang.Object

io.netty5.channel.ChannelHandlerAdapter

io.netty5.handler.codec.ByteToMessageDecoder

io.netty5.handler.codec.FixedLengthFrameDecoder

All Implemented Interfaces:

ChannelHandler

public class FixedLengthFrameDecoder
extends ByteToMessageDecoder

A decoder that splits the received Buffers 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 |
 +-----+-----+-----+
 

Nested Class Summary

Nested classes/interfaces inherited from class io.netty5.handler.codec.ByteToMessageDecoder

ByteToMessageDecoder.Cumulator

Field Summary

Fields inherited from class io.netty5.handler.codec.ByteToMessageDecoder

COMPOSITE_CUMULATOR, MERGE_CUMULATOR

Constructor Summary

Constructors

Constructor	Description
FixedLengthFrameDecoder(int frameLength)	Creates a new instance.
FixedLengthFrameDecoder(int frameLength, ByteToMessageDecoder.Cumulator cumulator)	Creates a new instance.

Method Summary

Modifier and Type	Method	Description
protected void	decode(ChannelHandlerContext ctx, Buffer in)	Decode the from one Buffer to another.
protected Object	decode0(ChannelHandlerContext ctx, Buffer in)	Create a frame out of the Buffer and return it.

Methods inherited from class io.netty5.handler.codec.ByteToMessageDecoder

actualReadableBytes, channelInactive, channelRead, channelReadComplete, channelShutdown, decodeLast, discardSomeReadBytes, handlerAdded, handlerAdded0, handlerRemoved, handlerRemoved0, internalBuffer, isSharable, isSingleDecode, setSingleDecode

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.netty5.channel.ChannelHandler

bind, channelActive, channelExceptionCaught, channelInboundEvent, channelRegistered, channelUnregistered, channelWritabilityChanged, close, connect, deregister, disconnect, flush, pendingOutboundBytes, read, register, sendOutboundEvent, shutdown, write

Constructor Detail

FixedLengthFrameDecoder

public FixedLengthFrameDecoder(int frameLength)

Creates a new instance.

Parameters:

frameLength - the length of the frame

FixedLengthFrameDecoder

public FixedLengthFrameDecoder(int frameLength,
                               ByteToMessageDecoder.Cumulator cumulator)

Creates a new instance.

Parameters:

frameLength - the length of the frame

Method Detail

decode

protected final void decode(ChannelHandlerContext ctx,
                            Buffer in)
                     throws Exception

Description copied from class: ByteToMessageDecoder

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

Specified by:

decode in class ByteToMessageDecoder

Parameters:

ctx - the ChannelHandlerContext which this ByteToMessageDecoder belongs to

in - the Buffer from which to read data

Throws:

Exception - is thrown if an error occurs

decode0

protected Object decode0(ChannelHandlerContext ctx,
                         Buffer in)
                  throws Exception

Create a frame out of the Buffer and return it.

Parameters:

ctx - the ChannelHandlerContext which this ByteToMessageDecoder belongs to

in - the Buffer from which to read data

Returns:

frame the Buffer which represent the frame or null if no frame could be created.

Throws:

Exception